140 results on '"Alexandra M. Johnstone"'
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2. Impact of age on the prevalence of poor-quality dietary variety, associated lifestyle factors, and body composition profile (low body muscle mass and high body fat mass) in older people residing in Colombo district, Sri Lanka
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Samantha Chandrika Vijewardane, Aindralal Balasuriya, Alexandra M. Johnstone, and Phyo Kyaw Myint
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Ageing ,Body composition ,Dietary variety ,Fat mass ,Older people ,Nutrition ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Aims: To assess the impact of age on the prevalence of poor-quality dietary variety, associated lifestyle factors, and body composition profile (low body muscle mass and high-fat mass) in older Sri Lankans. Methods: In this population-based cross-sectional study, older people of 60 years or above were selected using a multistage cluster sampling technique probability proportionate to the size. They were classified into 3 groups; 60–64, 65–69 and > 70-years. The poor-quality dietary variety was defined based on food variety, dietary diversity and dietary serving scores assessed using 24-h dietary recall. Body composition was measured using bio-electrical impedance. The impact of age on determinants of poor-quality dietary variety and being at risk of low muscle mass and high-fat mass were assessed by using multivariable logistic regression models. Results: Eight hundred older participants with a mean (SD) 68.1(5.8) years were included. There were 28.4%(n = 227), 36.2%(n = 290) and 35.4%(n = 283) in the 60–64, 65–69 and ≥ 70-year age groups, respectively. The prevalence of poor-quality dietary variety was similar across age groups. The urban living environment, and getting nutritional advice from the GP/hospital were found to have a significant negative association only in the 60–64 age group. A poor-quality dietary variety was significantly associated with no education or up to the primary level in the 65–69 age group and having diabetes or hypertension in the ≥70-year group. Odds of low muscle mass and high-fat mass were 2.43(1.46–4.03) and 2.17(1.30–3.63) respectively among the≥70-year age group compared to the 60-64-year group, after controlling for confounders. Conclusions: The prevalence of poor-quality dietary variety was similarly high in all age groups. Increasing age was associated with higher odds of low body muscle and high body fat mass despite similar dietary variety, indicating the need for special dietary attention.
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- 2024
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3. Education Intervention Has the Potential to Improve Short-Term Dietary Pattern among Older Adults with Undernutrition
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Samantha Chandrika Vijewardane, Aindralal Balasuriya, Alexandra M. Johnstone, and Phyo Kyaw Myint
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dietary pattern ,older adults ,nutrition education intervention ,community-based ,Geriatrics ,RC952-954.6 - Abstract
Low-cost educational interventions to improve dietary pattern is a pragmatic solution to prevent undernutrition in low- and middle-income countries. A prospective nutritional education intervention was conducted among older adults aged 60 years or above with undernutrition with 60 people in each intervention and control group. The objective was to develop and evaluate the efficacy of a community-based nutrition education intervention to improve the dietary pattern of older adults with undernutrition in Sri Lanka. The intervention consisted of two modules to improve the diversity, the variety of diet, and the serving sizes of food consumed. The primary outcome was the improvement of the Dietary Diversity Score (DDS) and the secondary outcomes were the Food Variety Score and Dietary Serving Score, which was assessed using the 24 h dietary recall. The mean difference in scores between the two groups was compared using the independent sample t-test at baseline, two weeks and three months post-intervention. Baseline characteristics were comparable. After two weeks, only the difference in DDS between the two groups was statistically significant (p = 0.002). However, this was not sustained at three months (p = 0.08). This study concludes that nutrition education interventions have the potential for short-term improvement in dietary patterns in older adults in a Sri Lanka setting.
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- 2023
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4. Comparing supermarket loyalty card data with traditional diet survey data for understanding how protein is purchased and consumed in older adults for the UK, 2014–16
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Mark A. Green, Anthony W. Watson, Jeffrey M. Brunstrom, Bernard M. Corfe, Alexandra M. Johnstone, Elizabeth A. Williams, and Emma Stevenson
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Protein ,Big data ,Supermarket loyalty cards ,Diet surveys ,Population ,Nutrition. Foods and food supply ,TX341-641 ,Nutritional diseases. Deficiency diseases ,RC620-627 - Abstract
Abstract Background Our ability to understand population-level dietary intake patterns is dependent on having access to high quality data. Diet surveys are common diet assessment methods, but can be limited by bias associated with under-reporting. Food purchases tracked using supermarket loyalty card records may supplement traditional surveys, however they are rarely available to academics and policy makers. The aim of our study is to explore population level patterns of protein purchasing and consumption in ageing adults (40 years onwards). Methods We used diet survey data from the National Diet and Nutrition Survey (2014–16) on food consumption, and loyalty card records on food purchases from a major high street supermarket retailer (2016–17) covering the UK. We computed the percentage of total energy derived from protein, protein intake per kg of body mass, and percentage of protein acquired by food type. Results We found that protein consumption (as the percentage of total energy purchased) increased between ages 40–65 years, and declined thereafter. In comparison, protein purchased in supermarkets was roughly 2–2.5 percentage points lower at each year of age. The proportion of adults meeting recommended levels of protein was lowest in age groups 55–69 and 70+. The time of protein consumption was skewed towards evening meals, with low intakes during breakfast or between main meals. Meat, fish and poultry dominated as sources of protein purchased and consumed, although adults also acquired a large share of their protein from dairy and bread, with little from plant protein. Conclusions Our study provides novel insights into how protein is purchased and consumed by ageing adults in the UK. Supermarket loyalty card data can reveal patterns of protein purchasing that when combined with traditional sources of dietary intake may enhance our understanding of dietary behaviours.
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- 2020
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5. Higher total faecal short-chain fatty acid concentrations correlate with increasing proportions of butyrate and decreasing proportions of branched-chain fatty acids across multiple human studies
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Maria LaBouyer, Grietje Holtrop, Graham Horgan, Silvia W. Gratz, Alvaro Belenguer, Nicola Smith, Alan W. Walker, Sylvia H. Duncan, Alexandra M. Johnstone, Petra Louis, Harry J. Flint, and Karen P. Scott
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Short chain fatty acids ,butyrate ,branched chain fatty acids ,human gut microbiota ,faecal pH ,Nutrition. Foods and food supply ,TX341-641 ,Nutritional diseases. Deficiency diseases ,RC620-627 - Abstract
Metabolites produced by microbial fermentation in the human intestine, especially short-chain fatty acids (SCFAs), are known to play important roles in colonic and systemic health. Our aim here was to advance our understanding of how and why their concentrations and proportions vary between individuals. We have analysed faecal concentrations of microbial fermentation acids from 10 human volunteer studies, involving 163 subjects, conducted at the Rowett Institute, Aberdeen, UK over a 7-year period. In baseline samples, the % butyrate was significantly higher, whilst % iso-butyrate and % iso-valerate were significantly lower, with increasing total SCFA concentration. The decreasing proportions of iso-butyrate and iso-valerate, derived from amino acid fermentation, suggest that fibre intake was mainly responsible for increased SCFA concentrations. We propose that the increase in % butyrate among faecal SCFA is largely driven by a decrease in colonic pH resulting from higher SCFA concentrations. Consistent with this, both total SCFA and % butyrate increased significantly with decreasing pH across five studies for which faecal pH measurements were available. Colonic pH influences butyrate production through altering the stoichiometry of butyrate formation by butyrate-producing species, resulting in increased acetate uptake and butyrate formation, and facilitating increased relative abundance of butyrate-producing species (notably Roseburia and Eubacterium rectale).
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- 2022
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6. Associations between ghrelin and leptin and neural food cue reactivity in a fasted and sated state
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Mirjam C.M. Wever, Floor van Meer, Lisette Charbonnier, Daniel R. Crabtree, William Buosi, Angeliki Giannopoulou, Odysseas Androutsos, Alexandra M. Johnstone, Yannis Manios, Claire L. Meek, Jens J. Holst, and Paul A.M. Smeets
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Food cue reactivity ,Appetite ,Hormones ,Ghrelin ,Leptin ,Visual food cues ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Food cue exposure can trigger eating. Food cue reactivity (FCR) is a conditioned response to food cues and includes physiological responses and activation of reward-related brain areas. FCR can be affected by hunger and weight status. The appetite-regulating hormones ghrelin and leptin play a pivotal role in homeostatic as well as hedonic eating. We examined the association between ghrelin and leptin levels and neural FCR in the fasted and sated state and the association between meal-induced changes in ghrelin and neural FCR, and in how far these associations are related to BMI and HOMA-IR. Data from 109 participants from three European centers (age 50±18 y, BMI 27±5 kg/m2) who performed a food viewing task during fMRI after an overnight fast and after a standardized meal were analyzed. Blood samples were drawn prior to the viewing task in which high-caloric, low-caloric and non-food images were shown. Fasting ghrelin was positively associated with neural FCR in the inferior and superior occipital gyrus in the fasted state. This was partly attributable to BMI and HOMA-IR. These brain regions are involved in visual attention, suggesting that individuals with higher fasting ghrelin have heightened attention to food cues. Leptin was positively associated with high calorie FCR in the medial prefrontal cortex (PFC) in the fasted state and to neural FCR in the left supramarginal gyrus in the fasted versus sated state, when correcting for BMI and HOMA-IR, respectively. This PFC region is involved in assessing anticipated reward value, suggesting that for individuals with higher leptin levels high-caloric foods are more salient than low-caloric foods, but foods in general are not more salient than non-foods. There were no associations between ghrelin and leptin and neural FCR in the sated state, nor between meal-induced changes in ghrelin and neural FCR. In conclusion, we show modest associations between ghrelin and leptin and neural FCR in a relatively large sample of European adults with a broad age and BMI range. Our findings indicate that people with higher leptin levels for their weight status and people with higher ghrelin levels may be more attracted to high caloric foods when hungry. The results of the present study form a foundation for future studies to test whether food intake and (changes in) weight status can be predicted by the association between (mainly fasting) ghrelin and leptin levels and neural FCR.
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- 2021
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7. Daily Fermented Whey Consumption Alters the Fecal Short-Chain Fatty Acid Profile in Healthy Adults
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Nicola M. Smith, Niamh G. Maloney, Sophie Shaw, Graham W. Horgan, Claire Fyfe, Jennifer C. Martin, Andy Suter, Karen P. Scott, and Alexandra M. Johnstone
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fermented whey concentrate ,microbiota ,short chain fatty acids ,dietary supplementation ,postbiotic ,Nutrition. Foods and food supply ,TX341-641 - Abstract
Gut microbiota influences many aspects of host health including immune, metabolic, and gut health. We examined the effect of a fermented whey concentrate (FWC) drink rich in L-(+)-Lactic acid, consumed daily, in 18 healthy men (n = 5) and women (n = 13) in free-living conditions.Objective: The aims of this 6-weeks pilot trial were to (i) identify changes in the gut microbiota composition and fecal short chain fatty acid (SCFA) profile, and (ii) to monitor changes in glucose homeostasis.Results: Total fecal SCFA (mM) concentration remained constant throughout the intervention. Proportionally, there was a significant change in the composition of different SCFAs compared to baseline. Acetate levels were significantly reduced (−6.5%; p < 0.01), coupled to a significant increase in the relative amounts of propionate (+2.2%; p < 0.01) and butyrate (+4.2%; p < 0.01), respectively. No changes in the relative abundance of any specific bacteria were detected. No significant changes were observed in glucose homeostasis in response to an oral glucose tolerance test.Conclusion: Daily consumption of a fermented whey product led to significant changes in fecal SCFA metabolite profile, indicating some potential prebiotic activity. These changes did not result in any detectable differences in microbiota composition. Post-hoc analysis indicated that baseline microbiota composition might be indicative of participants likely to see changes in SCFA levels. However, due to the lack of a control group these findings would need to be verified in a rigorously controlled trial. Future work is also required to identify the biological mechanisms underlying the observed changes in microbiota activity and to explore if these processes can be harnessed to favorably impact host health.Clinical Trial Registration: www.clinicaltrials.gov, identifier NCT03615339; retrospectively registered on 03/08/2018.
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- 2020
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8. Determinants of Undernutrition and Associated Factors of Low Muscle Mass and High Fat Mass among Older Men and Women in the Colombo District of Sri Lanka
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Samantha Chandrika Vijewardane, Aindralal Balasuriya, Phyo Kyaw Myint, and Alexandra M. Johnstone
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ageing adults ,body composition ,fat mass ,skeletal muscle mass ,undernutrition ,Geriatrics ,RC952-954.6 - Abstract
Undernutrition is a health challenge due to an expanding older population. The aims of the study were to assess the prevalence and determinants of undernutrition and, associated factors of low muscle and high fat mass among older men and women in the Colombo district of Sri Lanka. A cross sectional study was conducted using a multistage cluster sampling technique. Undernutrition was defined based on anthropometry and body composition assessed using bio-electrical impedance. Sex-specific multivariable logistic regression analyses were conducted. Of 800 participants (30.6% men), 35.3% were undernourished. The factors significantly associated with undernutrition among older women were hypertension with an adjusted odds ratio (aOR) (1.97; 1.36–2.88) and musculoskeletal disabilities aOR (2.19; 1.36–3.53). Among women, age ≥ 70 (1.79; 1.18–3.34) and diabetes (1.77; 1.10–2.84) were associated with low muscle mass and age ≥ 70 (2.05; 1.21–3.47), diabetes (2.20; 1.35–3.59) and disability in chewing (2.39; 1.30–4.40) were associated with high fat mass. Among men, age ≥ 70 years, no/up to grade 5 education, diabetes, visual disability, little/no responsibility in food shopping and not getting nutritional advice from media were associated with reduced odds of low muscle mass and no/up to grade 5 school education, disability in chewing and little/no responsibility in food shopping were associated with reduced odds of high fat mass. Undernutrition among older people is common in Sri Lanka. We have identified key factors associated with low muscle mass and high fat mass in this setting. Given the potential consequences of these conditions, our study provides potential targets for prevention of undernutrition and sarcopenic obesity.
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- 2022
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9. The Acute Effects of Breakfast Drinks with Varying Protein and Energy Contents on Appetite and Free-Living Energy Intake in UK Older Adults
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Daniel R. Crabtree, Adrian Holliday, William Buosi, Claire L. Fyfe, Graham W. Horgan, Alexandra M. Johnstone, and on behalf of the Full4Health-study Group
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ageing ,protein ,appetite ,energy intake ,BMI ,Geriatrics ,RC952-954.6 - Abstract
Proposed strategies for preventing protein deficiencies in older patients include increasing protein intake at breakfast. However, protein is highly satiating and the effects of very high protein intakes at breakfast on subsequent appetite and free-living energy intake (EI) in older adults are unclear. This study compared the acute effects of two breakfast drinks varying in protein and energy contents on appetite and free-living EI in healthy older adults using a randomized 2 × 2 crossover design. Participants (n = 48 (20 men, 28 women); mean ± SD age: 69 ± 3 years; BMI: 22.2 ± 2.0 kg·m−2; fat-free mass: 45.5 ± 8.0 kg) consumed two drinks for breakfast (high-protein (30.4 ± 5.3 g), low-energy (211.2 ± 37.1 kcal) content (HPLE) and very high-protein (61.8 ± 9.9 g), fed to energy requirements (428.0 ± 68.9 kcal) (VHPER)) one week apart. Appetite perceptions were assessed for 3 h post-drink and free-living EI was measured for the remainder of the day. Appetite was lower in VHPER than HPLE from 30 min onwards (p < 0.01). Free-living energy and protein intake did not differ between conditions (p = 0.814). However, 24 h EI (breakfast drink intake + free-living intake) was greater in VHPER than HPLE (1937 ± 568 kcal vs. 1705 ± 490 kcal; p = 0.001), as was 24 h protein intake (123.0 ± 26.0 g vs. 88.6 ± 20.9 g; p < 0.001). Consuming a very high-protein breakfast drink acutely suppressed appetite more than a low-energy, high-protein drink in older adults, though free-living EI was unaffected. The long-term effects of adopting such a breakfast strategy in older adults at high risk of energy and protein malnutrition warrants exploration.
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- 2022
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10. Sapogenol is a Major Microbial Metabolite in Human Plasma Associated with High Protein Soy-Based Diets: The Relevance for Functional Food Formulations
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Madalina Neacsu, Vassilios Raikos, Yara Benavides-Paz, Sylvia H. Duncan, Gary J. Duncan, James S. Christie, Alexandra M. Johnstone, and Wendy R. Russell
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soybean ,saponin ,sapogenol ,gut metabolism ,bioavailability ,human study ,Chemical technology ,TP1-1185 - Abstract
Legumes are a source of health-promoting macro- and micronutrients, but also contain numerous phytochemicals with useful biological activities, an example of which are saponins. Epidemiological studies suggest that saponins may play a role in protection from cancer and benefit human health by lowering cholesterol. Therefore, they could represent good candidates for specialised functional foods. Following the consumption of a soya-rich high-protein weight-loss diet (SOYA HP WL), the concentrations of Soyasaponin I (SSI) and soyasapogenol B (SSB) were determined in faecal samples from human volunteers (n = 10) and found to be between 1.4 and 17.5 mg per 100 g fresh faecal sample. SSB was the major metabolite identified in volunteers’ plasma (n = 10) after consumption of the soya test meal (SOYA MEAL); the postprandial (3 h after meal) plasma concentration for SSB varied between 48.5 ng/mL to 103.2 ng/mL. The metabolism of SSI by the gut microbiota (in vitro) was also confirmed. This study shows that the main systemic metabolites of soyasaponin are absorbed from the gut and that they are bioavailable in plasma predominantly as conjugates of sapogenol. The metabolism and bioavailability of biologically active molecules represent key information necessary for the efficient development of functional foods.
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- 2020
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11. Inadequacy of Protein Intake in Older UK Adults
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Susan Morris, James D. Cater, Mark A. Green, Alexandra M. Johnstone, Jeffrey M. Brunstrom, Emma J. Stevenson, Elizabeth A. Williams, and Bernard M. Corfe
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protein ,older adults ,protein intake ,protein requirement ,diurnal eating behavior ,Geriatrics ,RC952-954.6 - Abstract
The current dietary recommendation for protein intake in the UK is 0.75 g/kg/day, however, this population-wide recommendation does not necessarily reflect altered requirements for older adults to maintain muscle protein synthesis, nor does it encompass the potential impact of intake timing. Optimal muscle protein synthesis in older adults requires both higher intake requirements and a distribution of protein intake above a 25 g threshold, three times across the day. This study aimed to describe the protein intake of older adults in a UK region and compare the results to recommendations. The study re-assessed two existing datasets with rich diet information for older adults in the South Yorkshire area. Data were extracted from food diaries of 256 adults aged between 65 and 89 years old (mean ± SD 72.4 ± 5.3 years). Quantity and timing of intake were coded using Nutritics software and compared to recommendations. The relationship between body mass index (BMI), age, and protein intake was explored. Fewer than 50% of the participants met current UK recommendations (0.75 g/kg/day) and fewer than 15% met the ESPEN 1.2 g/kg/day age-specific recommendation. Only one participant met the 25 g/meal recommendation across three meals. These findings suggest that the older adult population is not achieving recommendations to maintain muscle protein synthesis. Nonetheless it identifies several straightforward opportunities for improvement, notably elevation of morning intake.
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- 2020
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12. Optimising Nutrition and Hydration in Care Homes—Getting It Right in Person Rather than in Policy
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Alison I. C. Donaldson, Alexandra M. Johnstone, and Phyo K. Myint
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nutrition ,dehydration ,care homes ,ageing ,frailty ,Geriatrics ,RC952-954.6 - Abstract
The scoping review by Bunn et al. identifies an important, but often invisible, challenge of malnutrition and specifically sub-optimal hydration and nutrition in the care home environment. Those requiring residential care are generally the frailest members of society, and likely to be affected by the anorexia of ageing: a multifactorial process whereby older people fail to adequately regulate food and nutrient intake resulting in unintentional weight loss. Adequate training of all healthcare professionals to recognise the risk of malnutrition at an early stage is fundamentally important, and the window of opportunity for intervention may be at a much earlier stage than admission to the care home. The specific needs of older adults must be considered in planning interventions with regard to the effects of ageing on physiology, digestion, and absorption of nutrients. Most importantly, we must offer person-centred care which offers residents an element of personal choice in whether or not they wish nutritional intervention, and any intervention offered must have the effect of improving quality of life rather than numbers on a scale.
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- 2018
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13. Care Home Research: Future Challenges and Opportunities
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Alexandra M. Johnstone and Alison I. C. Donaldson
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n/a ,Geriatrics ,RC952-954.6 - Abstract
The historical view of care homes as isolated communities is fading, with a new strong focus on offering person-centred care for residents that keeps them integrated in their community [...]
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- 2018
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14. Effects of hunger state on the brain responses to food cues across the life span.
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Lisette Charbonnier, Floor van Meer, Alexandra M. Johnstone, Daniel Crabtree, William Buosi, Yannis Manios, Odysseas Androutsos, Angeliki Giannopoulou, Max A. Viergever, and Paul A. M. Smeets
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- 2018
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15. Corrigendum to 'Effects of hunger state on the brain responses to food cues across the life span' [NeuroImage 171 (2018) 246-255].
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Lisette Charbonnier, Floor van Meer, Alexandra M. Johnstone, Daniel Crabtree, William Buosi, Yannis Manios, Odysseas Androutsos, Angeliki Giannopoulou, Max A. Viergever, and Paul A. M. Smeets
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- 2021
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16. Author response: The effects of caloric restriction on adipose tissue and metabolic health are sex- and age-dependent
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Yoshiko M Ikushima, Benjamin J Thomas, Karla J Suchacki, Kuan-Chan Chen, Claire Fyfe, Adriana AS Tavares, Richard J Sulston, Andrea Lovdel, Holly J Woodward, Xuan Han, Domenico Mattiucci, Eleanor J Brain, Carlos J Alcaide-Corral, Hiroshi Kobayashi, Gillian A Gray, Phillip D Whitfield, Roland H Stimson, Nicholas M Morton, Alexandra M Johnstone, and William P Cawthorn
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- 2023
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17. Hemp and buckwheat are valuable sources of dietary amino acids, beneficially modulating gastrointestinal hormones and promoting satiety in healthy volunteers
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Wendy R. Russell, Louise Cantlay, Madalina Neacsu, Alexandra M. Johnstone, Gary Duncan, Susan E. Anderson, Graham W. Horgan, C. L. Fyfe, Lorraine Scobbie, Salvatore Multari, Nicholas J. Vaughan, and Elisabeth Haljas
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Blood Glucose ,Male ,medicine.medical_treatment ,Medicine (miscellaneous) ,Phenylalanine ,Gastrointestinal Hormones ,chemistry.chemical_compound ,medicine ,Humans ,Insulin ,Food science ,Amino Acids ,Meals ,Cannabis ,Secoisolariciresinol ,Meal ,Cross-Over Studies ,Nutrition and Dietetics ,business.industry ,digestive, oral, and skin physiology ,Metabolism ,Postprandial Period ,Ghrelin ,Healthy Volunteers ,Postprandial ,Diabetes Mellitus, Type 2 ,chemistry ,Plant protein ,Female ,business ,Fagopyrum - Abstract
Purpose This study evaluated the postprandial effects following consumption of buckwheat, fava bean, pea, hemp and lupin compared to meat (beef); focussing on biomarkers of satiety, gut hormones, aminoacids and plant metabolites bioavailability and metabolism. Methods Ten subjects (n = 3 men; n = 7 women; 42 ± 11.8 years of age; BMI 26 ± 5.8 kg/m2) participated in six 1-day independent acute interventions, each meal containing 30 g of protein from buckwheat, fava bean, pea, hemp, lupin and meat (beef). Blood samples were collected during 24-h and VAS questionnaires over 5-h. Results Volunteers consumed significantly higher amounts of most amino acids from the meat meal, and with few exceptions, postprandial composition of plasma amino acids was not significantly different after consuming the plant-based meals. Buckwheat meal was the most satious (300 min hunger scores, p p = 0.01) found after hemp compared with the other plant-based meals. Decreased plasma ghrelin concentrations (iAUC p p p Conclusion Plants are valuable sources of amino acids which are promoting satiety. The impact of hemp and buckwheat on GLP-1 and, respectively, BCAAs should be explored further as could be relevant for aid and prevention of chronic diseases such as type 2 diabetes. Study registered with clinicaltrial.gov on 12th July 2013, study ID number: NCT01898351.
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- 2021
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18. Circadian Rhythms in Resting Metabolic Rate Account for Apparent Daily Rhythms in the Thermic Effect of Food
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Jonathan D. Johnston, Alexandra M. Johnstone, Peter J. Morgan, Alan Flanagan, and Leonie C. Ruddick-Collins
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Adult ,Male ,medicine.medical_specialty ,Evening ,Time Factors ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Context (language use) ,Diet induced thermogenesis ,Biochemistry ,Young Adult ,Endocrinology ,diet-induced thermogenesis ,Internal medicine ,energy expenditure ,Medicine ,Humans ,Resting energy expenditure ,Circadian rhythm ,diurnal ,Obesity ,Online Only Articles ,Clinical Research Articles ,Morning ,business.industry ,Biochemistry (medical) ,digestive, oral, and skin physiology ,chrononutrition ,breakfast ,Calorimetry, Indirect ,Thermogenesis ,Middle Aged ,Overweight ,Postprandial Period ,energy balance ,Circadian Rhythm ,Basal metabolic rate ,embryonic structures ,Female ,Basal Metabolism ,Specific dynamic action ,business ,Energy Intake ,AcademicSubjects/MED00250 - Abstract
Context Daily variation in the thermic effect of food (TEF) is commonly reported and proposed as a contributing factor to weight gain with late eating. However, underlying circadian variability in resting metabolic rate (RMR) is an overlooked factor when calculating TEF associated with eating at different times of the day. Objective This work aimed to determine whether methodological approaches to calculating TEF contribute to the reported phenomena of daily variation in TEF. Methods Fourteen overweight to obese but otherwise healthy individuals had their resting and postprandial energy expenditure (EE) measured over 15.5 hours at a clinical research unit. TEF was calculated for breakfast, lunch, and dinner using standard methods (above a baseline and premeal RMR measure) and compared to a method incorporating a circadian RMR by which RMR was derived from a sinusoid curve model and TEF was calculated over and above the continuously changing RMR. Main outcome measures were TEF at breakfast, lunch, and dinner calculated by different methods. Results Standard methods of calculating TEF above a premeal measured RMR showed that morning TEF (60.8 kcal ± 5.6) (mean ± SEM) was 1.6 times greater than TEF at lunch (36.3 kcal ± 8.4) and 2.4 times greater than dinner TEF (25.2 kcal ± 9.6) (P = .022). However, adjusting for modeled circadian RMR nullified any differences between breakfast (54.1 kcal ± 30.8), lunch (49.5 kcal ± 29.4), and dinner (49.1 kcal ± 25.7) (P = .680). Conclusion Differences in TEF between morning and evening can be explained by the underlying circadian resting EE, which is independent of an acute effect of eating.
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- 2021
19. Author Reply to Peer Reviews of The effects of caloric restriction on adipose tissue and metabolic health are sex- and age-dependent
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Karla J Suchacki, Benjamin J. Thomas, Claire Fyfe, Adriana Tavares, Richard J. Sulston, Andrea Lovdel, Holly J. Woodward, Xuan Han, Domenico Mattiucci, Eleanor J. Brain, Carlos Jose Alcaide-Corral, Gillian A. Gray, Phillip D. Whitfield, Roland H Stimson, Nik Morton, Alexandra M. Johnstone, and William P. Cawthorn
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- 2022
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20. MRC Hot Topic workshop report: Reshaping the food environment – applying interdisciplinary perspectives in appetite research
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Adrian Brown and Alexandra M. Johnstone
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Food insecurity ,Government ,Nutrition and Dietetics ,Behaviour change ,business.industry ,Political science ,Big data ,Strategic research ,Medicine (miscellaneous) ,Medical research ,business ,Food environment ,Management - Abstract
Acknowledgments Both AJ and AB and contributed equally to the writing of this article and gratefully acknowledge financial support from the UKRI Medical Research Council (Award MC_PC_19018, £9975) for supporting this workshop. Alex Johnstone gratefully acknowledges financial support from the Scottish Government as part of the Strategic Research Programme at The Rowett Institute (April 2016–March 2022). Adrian Brown gratefully acknowledges funding though the University College London and National Institute for Health Research (NIHR) Biomedical Research funding.
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- 2021
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21. The public health rationale for promoting plant protein as an important part of a sustainable and healthy diet
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Marta Lonnie and Alexandra M. Johnstone
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0301 basic medicine ,medicine.medical_specialty ,030109 nutrition & dietetics ,Nutrition and Dietetics ,Higher education ,business.industry ,Public health ,Medicine (miscellaneous) ,030209 endocrinology & metabolism ,Healthy diet ,Animal protein ,03 medical and health sciences ,0302 clinical medicine ,Dietary protein ,Plant protein ,Publishing ,Political science ,Sustainability ,medicine ,business ,Socioeconomics - Abstract
Open Access via Wiley publishing agreement. Rural and Environment Science and Analytical Services Division (GrantNumber(s): 1st April 2016 \ 31st March 2022) Minister of Science and Higher Education (GrantNumber(s): Project No. 010/RID/2018/19)
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- 2020
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22. Comparing supermarket loyalty card data with traditional diet survey data for understanding how protein is purchased and consumed in older adults for the UK, 2014–16
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Jeffrey M. Brunstrom, Mark A. Green, Emma J. Stevenson, Elizabeth A. Williams, Bernard M. Corfe, Alexandra M. Johnstone, and Anthony W. Watson
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0301 basic medicine ,population ,Medicine (miscellaneous) ,0302 clinical medicine ,big data ,Supermarket loyalty cards ,Diet surveys ,Loyalty ,Medicine ,Supermarkets ,lcsh:RC620-627 ,media_common ,education.field_of_study ,Nutrition and Behaviour ,Nutrition and Dietetics ,food and beverages ,Middle Aged ,lcsh:Nutritional diseases. Deficiency diseases ,Plant protein ,Physical and Mental Health ,lcsh:Nutrition. Foods and food supply ,Adult ,diet surveys ,Evening ,media_common.quotation_subject ,Population ,030209 endocrinology & metabolism ,lcsh:TX341-641 ,Clinical nutrition ,03 medical and health sciences ,Big data ,Environmental health ,Humans ,education ,Aged ,Consumption (economics) ,030109 nutrition & dietetics ,business.industry ,Research ,Protein ,Consumer Behavior ,United Kingdom ,Diet Surveys ,Diet ,Survey data collection ,supermarket loyalty cards ,business - Abstract
Background Our ability to understand population-level dietary intake patterns is dependent on having access to high quality data. Diet surveys are common diet assessment methods, but can be limited by bias associated with under-reporting. Food purchases tracked using supermarket loyalty card records may supplement traditional surveys, however they are rarely available to academics and policy makers. The aim of our study is to explore population level patterns of protein purchasing and consumption in ageing adults (40 years onwards). Methods We used diet survey data from the National Diet and Nutrition Survey (2014–16) on food consumption, and loyalty card records on food purchases from a major high street supermarket retailer (2016–17) covering the UK. We computed the percentage of total energy derived from protein, protein intake per kg of body mass, and percentage of protein acquired by food type. Results We found that protein consumption (as the percentage of total energy purchased) increased between ages 40–65 years, and declined thereafter. In comparison, protein purchased in supermarkets was roughly 2–2.5 percentage points lower at each year of age. The proportion of adults meeting recommended levels of protein was lowest in age groups 55–69 and 70+. The time of protein consumption was skewed towards evening meals, with low intakes during breakfast or between main meals. Meat, fish and poultry dominated as sources of protein purchased and consumed, although adults also acquired a large share of their protein from dairy and bread, with little from plant protein. Conclusions Our study provides novel insights into how protein is purchased and consumed by ageing adults in the UK. Supermarket loyalty card data can reveal patterns of protein purchasing that when combined with traditional sources of dietary intake may enhance our understanding of dietary behaviours.
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- 2020
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23. The effects of caloric restriction on adipose tissue and metabolic health are sex- and age-dependent
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Karla J. Suchacki, Ben J. Thomas, Yoshiko Matsumoto Ikushima, Kuan-Chan Chen, Claire Fyfe, Adriana A.S. Tavares, Richard J. Sulston, Andrea Lovdel, Holly J. Woodward, Xuan Han, Domenico Mattiucci, Eleanor J. Brain, Carlos J. Alcaide-Corral, Hiroshi Kobayashi, Gillian A. Gray, Phillip D. Whitfield, Roland H. Stimson, Nicholas M. Morton, Alexandra M. Johnstone, and William P. Cawthorn
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General Immunology and Microbiology ,PET/CT ,General Neuroscience ,General Medicine ,energy balance ,General Biochemistry, Genetics and Molecular Biology ,adipose tissue ,ageing ,Sex differences ,glucose homeostasis ,insulin sensitivity ,lipidomics ,caloric restriction ,liver metabolism - Abstract
SUMMARYCaloric restriction (CR) is a nutritional intervention that reduces the risk of age-related diseases in numerous species, including humans. CR’s metabolic effects, including decreased fat mass and improved insulin sensitivity, play an important role in its broader health benefits. However, the extent and basis of sex differences in CR’s health benefits are unknown. We found that 30% CR in young (3-month-old) male mice decreased fat mass and improved glucose tolerance and insulin sensitivity, whereas these effects were blunted or absent in young female mice. Females’ resistance to fat and weight loss was associated with decreased lipolysis, lower systemic energy expenditure and fatty acid oxidation, and increased postprandial lipogenesis compared to males. Positron emission tomography-computed tomography (PET/CT) with18F-fluorodeoxyglucose (18F-FDG) showed that peripheral glucose uptake was comparable between sexes. Instead, the sex differences in glucose homeostasis were associated with altered hepatic ceramide content and substrate metabolism: compared to CR males, CR females had lower TCA cycle activity but higher blood ketone concentrations, a marker of hepatic acetyl-CoA content. This suggests that males use hepatic acetyl-CoA for the TCA cycle whereas in females it accumulates, thereby stimulating gluconeogenesis and limiting hypoglycaemia during CR. In aged mice (18-months old), when females are anoestrus, CR decreased fat mass and improved glucose homeostasis to a similar extent in both sexes. Finally, in a cohort of overweight and obese humans CR-induced fat loss was also sex- and age-dependent: younger females (45 years) this sex difference was absent. Collectively, these studies identify age-dependent sex differences in the metabolic effects of CR and highlight adipose tissue, the liver and oestrogen as key determinants of CR’s metabolic benefits. These findings have important implications for understanding the interplay between diet and health and for maximising the benefits of CR in humans.HIGHLIGHTSCaloric restriction (CR) decreases fat mass and improves glucose homeostasis in young male mice, but young females resist these effects.CR females resist lipolysis, decrease energy expenditure and increase postprandial lipogenesis more than CR males, explaining how females resist fat loss.Sex differences in glucose homeostasis are associated with altered hepatic metabolism and gluconeogenesis, without marked differences in peripheral glucose uptake.CR’s effects on fat loss and glucose homeostasis are comparable in aged male and female mice, implicating oestrogen as the driver of the sexually dimorphic effects in young mice.In humans, females resist CR-induced fat loss in an age-dependent manner, further supporting the role of oestrogen in the sexually dimorphic effects of CR.
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- 2022
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24. The Acute Effects of Breakfast Drinks with Varying Protein and Energy Contents on Appetite and Free-Living Energy Intake in UK Older Adults
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Daniel R, Crabtree, Adrian, Holliday, William, Buosi, Claire L, Fyfe, Graham W, Horgan, Alexandra M, Johnstone, and On Behalf Of The Full Health-Study Group
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Aging ,Health (social science) ,ageing ,protein ,appetite ,energy intake ,BMI ,digestive, oral, and skin physiology ,Geriatrics and Gerontology ,Gerontology - Abstract
Proposed strategies for preventing protein deficiencies in older patients include increasing protein intake at breakfast. However, protein is highly satiating and the effects of very high protein intakes at breakfast on subsequent appetite and free-living energy intake (EI) in older adults are unclear. This study compared the acute effects of two breakfast drinks varying in protein and energy contents on appetite and free-living EI in healthy older adults using a randomized 2 × 2 crossover design. Participants (n = 48 (20 men, 28 women); mean ± SD age: 69 ± 3 years; BMI: 22.2 ± 2.0 kg·m−2; fat-free mass: 45.5 ± 8.0 kg) consumed two drinks for breakfast (high-protein (30.4 ± 5.3 g), low-energy (211.2 ± 37.1 kcal) content (HPLE) and very high-protein (61.8 ± 9.9 g), fed to energy requirements (428.0 ± 68.9 kcal) (VHPER)) one week apart. Appetite perceptions were assessed for 3 h post-drink and free-living EI was measured for the remainder of the day. Appetite was lower in VHPER than HPLE from 30 min onwards (p < 0.01). Free-living energy and protein intake did not differ between conditions (p = 0.814). However, 24 h EI (breakfast drink intake + free-living intake) was greater in VHPER than HPLE (1937 ± 568 kcal vs. 1705 ± 490 kcal; p = 0.001), as was 24 h protein intake (123.0 ± 26.0 g vs. 88.6 ± 20.9 g; p < 0.001). Consuming a very high-protein breakfast drink acutely suppressed appetite more than a low-energy, high-protein drink in older adults, though free-living EI was unaffected. The long-term effects of adopting such a breakfast strategy in older adults at high risk of energy and protein malnutrition warrants exploration.
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- 2021
25. The effects of caloric restriction on adipose tissue and metabolic health are sex- and age-dependent
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Adriana As Tavares, Gillian A. Gray, Carlos J. Alcaide-Corral, Roland Stimson, Eleanor Brain, William P. Cawthorn, Phillip Whitfield, Domenico Mattiucci, Benjamin J. Thomas, Nicholas M. Morton, Xuan Han, Claire Fyfe, Alexandra M. Johnstone, Karla Suckacki, Andrea Lovdel, Richard J. Sulston, and Holly Woodward
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medicine.medical_specialty ,Endocrinology ,business.industry ,Internal medicine ,medicine ,Caloric theory ,Adipose tissue ,Age dependent ,business ,Metabolic health - Published
- 2021
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26. Investigating the Effectiveness of Very Low-Calorie Diets and Low-Fat Vegan Diets on Weight and Glycemic Markers in Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis
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Anjali Kashyap, Alexander Mackay, Ben Carter, Claire L. Fyfe, Alexandra M. Johnstone, and Phyo K. Myint
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Glycated Hemoglobin ,Blood Glucose ,Diet, Vegan ,Nutrition and Dietetics ,Diabetes Mellitus, Type 2 ,Humans ,Diet, Fat-Restricted ,Biomarkers ,Caloric Restriction ,Food Science - Abstract
Caloric restriction and vegan diets have demonstrated protective effects for diabetes, however their role in improving clinically relevant outcomes has not been summarized. Our aim was to evaluate the evidence for low-calorie diets (VLCD) and vegan diets on weight and glycemic control in the management of patients with Type 2 Diabetes. Database searches were conducted using Cochrane Library, MEDLINE (Ovid) and Embase. Systematic Review Registration: CRD42022310299. Methodological quality of studies was assessed using Cochrane RoB Tool for RCTs, Cochrane ROBINS-I RoB Tool for non-RCTs and NIH Quality Assessment tool for other studies. Sixteen studies with a total of 834 individuals were included and assessed to have a moderate to high risk of bias. Statistically significant changes in weight, BMI, and HbA1c were not observed in vegan diet cohorts. However, LDL cholesterol was significantly decreased by vegan diet. VLCDs significantly improved glycaemic control, with reductions in fasting glucose, pooled mean difference (MD) −1.51 mmol/L (95% CI −2.89, −0.13; p = 0.03; 2 studies) and HbA1c, pooled MD −0.66% (95% CI −1.28, −0.03; p = 0.04; 3 studies) compared to non-dietary therapy. Both diets suggested a trend towards improved weight loss and anthropometric markers vs. control. VLCD diet intervention is associated with improvement in glycaemia control in patients with Type 2 Diabetes.
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- 2022
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27. Timing of daily calorie loading affects appetite and hunger responses without changes in energy metabolism in healthy subjects with obesity
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Leonie C. Ruddick-Collins, Peter J. Morgan, Claire L. Fyfe, Joao A.N. Filipe, Graham W. Horgan, Klaas R. Westerterp, Jonathan D. Johnston, Alexandra M. Johnstone, Humane Biologie, and RS: NUTRIM - R1 - Obesity, diabetes and cardiovascular health
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Diet, Reducing ,Hunger ,Physiology ,Weight Loss ,Animals ,Appetite ,Humans ,Obesity ,Cell Biology ,Energy Intake ,Energy Metabolism ,Molecular Biology ,Healthy Volunteers - Abstract
Morning loaded calorie intake in humans has been advocated as a dietary strategy to improve weight loss. This is also supported by animal studies suggesting time of eating can prevent weight gain. However, the underlying mechanisms through which timing of eating could promote weight loss in humans are unclear. In a randomized crossover trial (NCT03305237), 30 subjects with obesity/overweight underwent two 4-week calorie-restricted but isoenergetic weight loss diets, with morning loaded or evening loaded calories (45%:35%:20% versus 20%:35%:45% calories at breakfast, lunch, and dinner, respectively). We demonstrate no differences in total daily energy expenditure or resting metabolic rate related to the timing of calorie distribution, and no difference in weight loss. Participants consuming the morning loaded diet reported significantly lower hunger. Thus, morning loaded intake (big breakfast) may assist with compliance to weight loss regime through a greater suppression of appetite.
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- 2022
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28. The Ageing Gut–Brain study: Exploring the role of the gut microbiota in dementia
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Phyo K. Myint, Alison I C Donaldson, Karen P. Scott, and Alexandra M. Johnstone
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0301 basic medicine ,Government ,030109 nutrition & dietetics ,Nutrition and Dietetics ,biology ,Endowment ,Medicine (miscellaneous) ,Library science ,030209 endocrinology & metabolism ,Gut flora ,biology.organism_classification ,medicine.disease ,03 medical and health sciences ,0302 clinical medicine ,Political science ,Strategic research ,medicine ,Dementia - Abstract
Alex Johnstone, Alison Donaldson, Karen Scott and Phyo Myint all contributed equally to the writing and preparation of the manuscript. This study is funded by Tenovus Scotland Research Project No. G16‐08 (start 1 June 2017, end date 31 January 2019) and NHS‐Grampian Research and Development Endowment Research Grants Project No: 16/11/043 (start date 1 April 2017, end date 31 January, 2019) and the Scottish government as part of the Strategic Research Programme at the Rowett Institute (start date 1 April 2016–31 March 2021).
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- 2019
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29. Salivary ghrelin response to drinks varying in protein content and quantity and association with energy intake and appetite
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Jens J. Holst, William Buosi, Daniel R Crabtree, Graham W. Horgan, C. L. Fyfe, and Alexandra M. Johnstone
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Adult ,Saliva ,medicine.medical_specialty ,media_common.quotation_subject ,Appetite ,Experimental and Cognitive Psychology ,Protein content ,Behavioral Neuroscience ,Total Ghrelin ,Internal medicine ,Orexigenic ,medicine ,Humans ,Meals ,media_common ,Cross-Over Studies ,business.industry ,digestive, oral, and skin physiology ,Postprandial Period ,Ghrelin ,Endocrinology ,Postprandial ,business ,Energy Intake ,medicine.drug ,Hormone - Abstract
Salivary hormone analysis is a non-invasive alternative to blood-borne hormone analysis. The orexigenic hormone ghrelin has been detected in human saliva, though the relationship between salivary and blood-borne ghrelin and salivary ghrelin's association with energy intake (EI) and appetite remains unclear. The primary aim of this study was to compare salivary and plasma ghrelin responses to dairy breakfast drinks varying in protein content and quantity, and to determine the relationship between salivary ghrelin and EI and appetite. Participants (n = 25) consumed four test drinks, varying in protein content and quantity, on four separate days in a double-blind randomized controlled study. Salivary and plasma total ghrelin were measured at 0, 30, 60 and 120 min and appetite perceptions at 0, 30, 60, 90 and 120 min. A buffet-style test meal was presented at 120 min to measure ad libitum EI. There was no correlation between the sample means for fasted salivary and plasma ghrelin (r = 0.099, p = 0.637). Furthermore, there was no within-participant association between fasted salivary and plasma ghrelin (r = -0.041, p = 0.725). Mean bias between fasted salivary and plasma ghrelin was -448 pg/ml (95% confidence intervals (CI) = -623 - -273 pg/ml) and upper and lower limits of agreement (LOA) were 427 pg/ml and -1324 pg/ml, respectively. Variation in postprandial levels of salivary and plasma ghrelin within-participants were not associated (r = -0.004, p = 0.943). There was no significant association between EI and salivary (r = 0.003, p = 0.979) or plasma (r = -0.080, p = 0.492) ghrelin. Salivary ghrelin was not significantly correlated with composite appetite score (r = 0.023; p = 0.654), though plasma ghrelin was (r = 0.225, p 0.001). Mean bias between postprandial salivary and plasma ghrelin was -210 pg/ml (95% CI = -380 - -40 pg/ml) and upper and lower LOA were 641 pg/ml and -1061 pg/ml, respectively. These findings suggest that salivary and plasma ghrelin responses to drinks varying in protein content and quantity are unrelated and that salivary ghrelin is not associated with EI or appetite perceptions in healthy non-obese adults. This trial was registered at www.clinicaltrial.gov (NCT01597024).
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- 2021
30. Associations between ghrelin and leptin and neural food cue reactivity in a fasted and sated state
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Claire L Meek, William Buosi, Daniel R Crabtree, Jens J. Holst, Lisette Charbonnier, Floor van Meer, Angeliki Giannopoulou, Yannis Manios, Alexandra M. Johnstone, Paul A.M. Smeets, Mirjam C.M. Wever, and Odysseas Androutsos
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Adult ,Male ,Leptin ,medicine.medical_specialty ,Calorie ,Hunger ,Cognitive Neuroscience ,media_common.quotation_subject ,Appetite ,Neurosciences. Biological psychiatry. Neuropsychiatry ,chemical and pharmacologic phenomena ,Visual food cues ,Satiety Response ,Food cue reactivity ,Internal medicine ,Medicine ,Humans ,Obesity ,Prefrontal cortex ,Sensory Science and Eating Behaviour ,media_common ,VLAG ,Aged ,Meal ,business.industry ,digestive, oral, and skin physiology ,Brain ,Fasting ,Middle Aged ,Overweight ,medicine.disease ,Magnetic Resonance Imaging ,Ghrelin ,Hormones ,Endocrinology ,Sensoriek en eetgedrag ,Neurology ,Food ,Female ,Cues ,business ,hormones, hormone substitutes, and hormone antagonists ,Biomarkers ,Hormone ,RC321-571 - Abstract
Food cue exposure can trigger eating. Food cue reactivity (FCR) is a conditioned response to food cues and includes physiological responses and activation of reward-related brain areas. FCR can be affected by hunger and weight status. The appetite-regulating hormones ghrelin and leptin play a pivotal role in homeostatic as well as hedonic eating. We examined the association between ghrelin and leptin levels and neural FCR in the fasted and sated state and the association between meal-induced changes in ghrelin and neural FCR, and in how far these associations are related to BMI and HOMA-IR. Data from 109 participants from three European centers (age 50±18 y, BMI 27±5 kg/m2) who performed a food viewing task during fMRI after an overnight fast and after a standardized meal were analyzed. Blood samples were drawn prior to the viewing task in which high-caloric, low-caloric and non-food images were shown. Fasting ghrelin was positively associated with neural FCR in the inferior and superior occipital gyrus in the fasted state. This was partly attributable to BMI and HOMA-IR. These brain regions are involved in visual attention, suggesting that individuals with higher fasting ghrelin have heightened attention to food cues. Leptin was positively associated with high calorie FCR in the medial prefrontal cortex (PFC) in the fasted state and to neural FCR in the left supramarginal gyrus in the fasted versus sated state, when correcting for BMI and HOMA-IR, respectively. This PFC region is involved in assessing anticipated reward value, suggesting that for individuals with higher leptin levels high-caloric foods are more salient than low-caloric foods, but foods in general are not more salient than non-foods. There were no associations between ghrelin and leptin and neural FCR in the sated state, nor between meal-induced changes in ghrelin and neural FCR. In conclusion, we show modest associations between ghrelin and leptin and neural FCR in a relatively large sample of European adults with a broad age and BMI range. Our findings indicate that people with higher leptin levels for their weight status and people with higher ghrelin levels may be more attracted to high caloric foods when hungry. The results of the present study form a foundation for future studies to test whether food intake and (changes in) weight status can be predicted by the association between (mainly fasting) ghrelin and leptin levels and neural FCR.
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- 2021
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31. Appetite Control across the Lifecourse: The Acute Impact of Breakfast Drink Quantity and Protein Content. The Full4Health Project
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Angeliki Giannopoulou, C. L. Fyfe, Jens J. Holst, Odysseas Androutsos, Klaske van Norren, William Buosi, Kristine Beaulieu, Graham Finlayson, Julian G. Mercer, Claire L Meek, Yannis Manios, Alexandra M. Johnstone, Daniel R Crabtree, Graham W. Horgan, Crabtree, Daniel R. [0000-0003-2013-9109], Buosi, William [0000-0002-3153-8896], Fyfe, Claire L. [0000-0001-6521-2651], Horgan, Graham W. [0000-0002-6048-1374], Manios, Yannis [0000-0001-6486-114X], Finlayson, Graham [0000-0002-5620-2256], Beaulieu, Kristine [0000-0001-8926-6953], Holst, Jens J. [0000-0001-6853-3805], Van Norren, Klaske [0000-0002-6281-9455], Johnstone, Alexandra M. [0000-0002-5484-292X], Apollo - University of Cambridge Repository, Crabtree, Daniel R [0000-0003-2013-9109], Fyfe, Claire L [0000-0001-6521-2651], Horgan, Graham W [0000-0002-6048-1374], Holst, Jens J [0000-0001-6853-3805], Van Norren, Klaske Van [0000-0002-6281-9455], and Johnstone, Alexandra M [0000-0002-5484-292X]
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0301 basic medicine ,Male ,FOOD-INTAKE ,gut hormones ,Hunger ,Appetite ,0302 clinical medicine ,Glucagon-Like Peptide 1 ,Surveys and Questionnaires ,Weight management ,Homeostasis ,PLASMA GHRELIN LEVELS ,Child ,media_common ,INSULIN-RESISTANCE ,Nutrition and Dietetics ,Leptin ,digestive, oral, and skin physiology ,Lifecourse ,Middle Aged ,Nutritional Biology ,Postprandial ,appetite ,lifecourse ,Ghrelin ,Female ,GROWTH-HORMONE ,MENSTRUAL-CYCLE ,lcsh:Nutrition. Foods and food supply ,PEPTIDE-YY ,Adult ,FAT-FREE MASS ,medicine.medical_specialty ,Adolescent ,media_common.quotation_subject ,lcsh:TX341-641 ,030209 endocrinology & metabolism ,Satiation ,Article ,hunger ,03 medical and health sciences ,Young Adult ,Double-Blind Method ,Internal medicine ,medicine ,Humans ,Peptide YY ,Aged ,Breakfast ,030109 nutrition & dietetics ,business.industry ,Protein ,Gut hormones ,ENERGY-INTAKE ,Endocrinology ,Glucose ,Basal metabolic rate ,RICH BREAKFAST ,Anorectic ,business ,Energy Intake ,protein ,Biomarkers ,Food Science - Abstract
Understanding the mechanisms of hunger, satiety and how nutrients affect appetite control is important for successful weight management across the lifecourse. The primary aim of this study was to describe acute appetite control across the lifecourse, comparing age groups (children, adolescents, adults, elderly), weight categories, genders and European sites (Scotland and Greece). Participants (n = 391) consumed four test drinks, varying in composition (15% (normal protein, NP) and 30% (high protein, HP) of energy from protein) and quantity (based on 100% basal metabolic rate (BMR) and 140% BMR), on four separate days in a double-blind randomized controlled study. Ad libitum energy intake (EI), subjective appetite and biomarkers of appetite and metabolism (adults and elderly only) were measured. The adults&rsquo, appetite was significantly greater than that of the elderly across all drink types (p <, 0.004) and in response to drink quantities (p <, 0.001). There were no significant differences in EI between age groups, weight categories, genders or sites. Concentrations of glucagon-like peptide 1 (GLP-1) and peptide YY (PYY) were significantly greater in the elderly than the adults (p <, 0.001). Ghrelin and fasting leptin concentrations differed significantly between weight categories, genders and sites (p <, 0.05), while GLP-1 and PYY concentrations differed significantly between genders only (p <, 0.05). Compared to NP drinks, HP drinks significantly increased postprandial GLP-1 and PYY (p <, 0.001). Advanced age was concomitant with reduced appetite and elevated anorectic hormone release, which may contribute to the development of malnutrition. In addition, appetite hormone concentrations differed between weight categories, genders and geographical locations.
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- 2020
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32. Daily Fermented Whey Consumption Alters the Fecal Short-Chain Fatty Acid Profile in Healthy Adults
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Andreas Suter, Jennifer C. Martin, Graham W. Horgan, Karen P. Scott, Sophie Shaw, Alexandra M. Johnstone, Niamh G. Maloney, C. L. Fyfe, and Nicola Smith
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0301 basic medicine ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,030209 endocrinology & metabolism ,lcsh:TX341-641 ,Butyrate ,Gut flora ,03 medical and health sciences ,0302 clinical medicine ,postbiotic ,medicine ,microbiota ,Glucose homeostasis ,Food science ,Feces ,Nutrition ,chemistry.chemical_classification ,030109 nutrition & dietetics ,Nutrition and Dietetics ,biology ,Prebiotic ,Short-chain fatty acid ,Metabolism ,dietary supplementation ,biology.organism_classification ,Clinical Trial ,chemistry ,Propionate ,sense organs ,short chain fatty acids ,lcsh:Nutrition. Foods and food supply ,fermented whey concentrate ,Food Science - Abstract
Gut microbiota influences many aspects of host health including immune, metabolic, and gut health. We examined the effect of a fermented whey concentrate (FWC) drink rich in L-(+)-Lactic acid, consumed daily, in 18 healthy men (n = 5) and women (n = 13) in free-living conditions.Objective: The aims of this 6-weeks pilot trial were to (i) identify changes in the gut microbiota composition and fecal short chain fatty acid (SCFA) profile, and (ii) to monitor changes in glucose homeostasis.Results: Total fecal SCFA (mM) concentration remained constant throughout the intervention. Proportionally, there was a significant change in the composition of different SCFAs compared to baseline. Acetate levels were significantly reduced (−6.5%; p < 0.01), coupled to a significant increase in the relative amounts of propionate (+2.2%; p < 0.01) and butyrate (+4.2%; p < 0.01), respectively. No changes in the relative abundance of any specific bacteria were detected. No significant changes were observed in glucose homeostasis in response to an oral glucose tolerance test.Conclusion: Daily consumption of a fermented whey product led to significant changes in fecal SCFA metabolite profile, indicating some potential prebiotic activity. These changes did not result in any detectable differences in microbiota composition. Post-hoc analysis indicated that baseline microbiota composition might be indicative of participants likely to see changes in SCFA levels. However, due to the lack of a control group these findings would need to be verified in a rigorously controlled trial. Future work is also required to identify the biological mechanisms underlying the observed changes in microbiota activity and to explore if these processes can be harnessed to favorably impact host health.Clinical Trial Registration: www.clinicaltrials.gov, identifier NCT03615339; retrospectively registered on 03/08/2018.
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- 2020
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33. Mealtime: A circadian disruptor and determinant of energy balance?
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Leonie C. Ruddick-Collins, Alexandra M. Johnstone, and Peter J. Morgan
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medicine.medical_specialty ,Time Factors ,Endocrinology, Diabetes and Metabolism ,Circadian clock ,030209 endocrinology & metabolism ,Biology ,Mice ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Endocrinology ,Circadian Clocks ,Internal medicine ,Weight management ,Zeitgeber ,medicine ,Animals ,Humans ,Endocrine system ,Circadian rhythm ,Meals ,Endocrine and Autonomic Systems ,Leptin ,Feeding Behavior ,Circadian Rhythm ,Ghrelin ,Energy Intake ,Energy Metabolism ,Neuroscience ,030217 neurology & neurosurgery ,Hormone - Abstract
Circadian rhythms play a critical role in the physiological processes involved in energy metabolism and energy balance (EB). A large array of metabolic processes, including the expression of many energy-regulating endocrine hormones, display temporal rhythms that are driven by both the circadian clock and food intake. Mealtime has been shown to be a compelling zeitgeber in peripheral tissue rhythms. Inconsistent signalling to the periphery, because of mismatched input from the central clock vs time of eating, results in circadian disruption in which central and/or peripheral rhythms are asynchronously time shifted or their amplitudes reduced. A growing body of evidence supports the negative health effects of circadian disruption, with strong evidence in murine models that mealtime-induced circadian disruption results in various metabolic consequences, including energy imbalance and weight gain. Increased weight gain has been reported to occur even without differences in energy intake, indicating an effect of circadian disruption on energy expenditure. However, the translation of these findings to humans is not well established because the ability to undertake rigorously controlled dietary studies that explore the chronic effects on energy regulation is challenging. Establishing the neuroendocrine changes in response to both acute and chronic variations in mealtime, along with observations in populations with routinely abnormal mealtimes, may provide greater insight into underlying mechanisms that influence long-term weight management under different meal patterns. Human studies should explore mechanisms through relevant biomarkers; for example, cortisol, leptin, ghrelin and other energy-regulating neuroendocrine factors. Mistiming between aggregate hormonal signals, or between hormones with their receptors, may cause reduced signalling intensity and hormonal resistance. Understanding how mealtimes may impact on the coordination of endocrine factors is essential for untangling the complex regulation of EB. Here a review is provided on current evidence of the impacts of mealtime on energy metabolism and the underlying neuroendocrine mechanisms, with a specific focus on human research.
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- 2020
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34. Nondigestible Carbohydrates Affect Metabolic Health and Gut Microbiota in Overweight Adults after Weight Loss
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Hannah McKinnon, Alexandra M. Johnstone, Silvia W. Gratz, Graham W. Horgan, C. L. Fyfe, Sheila Ryan, Jennifer Kelly, Soraya P. Shirazi-Beechey, Jo Harrold, Reyna Romero-Gonzalez, Carmen Frontela-Saseta, Angela Bonnema, Douwina Bosscher, Jason C.G. Halford, Sylvia H. Duncan, Harry J. Flint, Erik Näslund, Xiaolei Ze, Gaspar Ros-Berruezo, and Rubén López-Nicolás
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Adult ,DNA, Bacterial ,Dietary Fiber ,Male ,0301 basic medicine ,food.ingredient ,Diet, Reducing ,media_common.quotation_subject ,Medicine (miscellaneous) ,Gut flora ,Overweight ,Feces ,Young Adult ,03 medical and health sciences ,food ,Animal science ,Weight loss ,RNA, Ribosomal, 16S ,Glucose Intolerance ,Weight Loss ,Blood plasma ,Humans ,Medicine ,Resistant starch ,media_common ,030109 nutrition & dietetics ,Nutrition and Dietetics ,Bacteria ,biology ,business.industry ,Appetite ,Middle Aged ,medicine.disease ,biology.organism_classification ,Lipids ,Crossover study ,Obesity ,Gastrointestinal Microbiome ,RNA, Bacterial ,030104 developmental biology ,Female ,medicine.symptom ,business - Abstract
Background The composition of diets consumed following weight loss (WL) can have a significant impact on satiety and metabolic health. Objective This study was designed to test the effects of including a nondigestible carbohydrate to achieve weight maintenance (WM) following a period of WL. Methods Nineteen volunteers [11 females and 8 males, aged 20–62 y; BMI (kg/m2): 27–42] consumed a 3-d maintenance diet (15%:30%:55%), followed by a 21-d WL diet (WL; 30%:30%:40%), followed by 2 randomized 10-d WM diets (20%:30%:50% of energy from protein:fat:carbohydrate) containing either resistant starch type 3 (RS-WM; 22 or 26 g/d for females and males, respectively) or no RS (C-WM) in a within-subject crossover design without washout periods. The primary outcome, WM after WL, was analyzed by body weight. Secondary outcomes of fecal microbiota composition and microbial metabolite concentrations and gut hormones were analyzed in fecal samples and blood plasma, respectively. All outcomes were assessed at the end of each dietary period. Results Body weight was similar after the RS-WM and C-WM diets (90.7 and 90.8 kg, respectively), with no difference in subjectively rated appetite. During the WL diet period plasma ghrelin increased by 36% (P < 0.001), glucose-dependent insulinotropic polypeptide (GIP) decreased by 33% (P < 0.001), and insulin decreased by 46% (P < 0.001), but no significant differences were observed during the RS-WM and C-WM diet periods. Fasting blood glucose was lower after the RS-WM diet (5.59 ± 0.31 mmol/L) than after the C-WM diet [5.75 ± 0.49 mmol/L; P = 0.015; standard error of the difference between the means (SED): 0.09]. Dietary treatments influenced the fecal microbiota composition (R2 = 0.054, P = 0.031) but not diversity. Conclusions The metabolic benefits, for overweight adults, from WL were maintained through a subsequent WM diet with higher total carbohydrate intake. Inclusion of resistant starch in the WM diet altered gut microbiota composition positively and resulted in lower fasting glucose compared with the control, with no apparent change in appetite. This trial was registered at clinicaltrials.gov as NCT01724411.
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- 2020
35. Sapogenol is a Major Microbial Metabolite in Human Plasma Associated with High Protein Soy-Based Diets: The Relevance for Functional Food Formulations
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Yara Benavides-Paz, James S. Christie, Alexandra M. Johnstone, Sylvia H. Duncan, Gary Duncan, Madalina Neacsu, Wendy R. Russell, and Vassilios Raikos
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Health (social science) ,Metabolite ,Plant Science ,Gut flora ,lcsh:Chemical technology ,Health Professions (miscellaneous) ,Microbiology ,Article ,functional food ,chemistry.chemical_compound ,Functional food ,gut metabolism ,sapogenol ,human study ,lcsh:TP1-1185 ,Food science ,soybean ,saponin ,Meal ,biology ,Chemistry ,Cholesterol ,digestive, oral, and skin physiology ,biology.organism_classification ,Micronutrient ,Bioavailability ,bioavailability ,Postprandial ,Food Science - Abstract
Legumes are a source of health-promoting macro- and micronutrients, but also contain numerous phytochemicals with useful biological activities, an example of which are saponins. Epidemiological studies suggest that saponins may play a role in protection from cancer and benefit human health by lowering cholesterol. Therefore, they could represent good candidates for specialised functional foods. Following the consumption of a soya-rich high-protein weight-loss diet (SOYA HP WL), the concentrations of Soyasaponin I (SSI) and soyasapogenol B (SSB) were determined in faecal samples from human volunteers (n = 10) and found to be between 1.4 and 17.5 mg per 100 g fresh faecal sample. SSB was the major metabolite identified in volunteers’ plasma (n = 10) after consumption of the soya test meal (SOYA MEAL); the postprandial (3 h after meal) plasma concentration for SSB varied between 48.5 ng/mL to 103.2 ng/mL. The metabolism of SSI by the gut microbiota (in vitro) was also confirmed. This study shows that the main systemic metabolites of soyasaponin are absorbed from the gut and that they are bioavailable in plasma predominantly as conjugates of sapogenol. The metabolism and bioavailability of biologically active molecules represent key information necessary for the efficient development of functional foods.
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- 2020
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36. Comparison of meat versus soya based high-protein diets on faecal microbiota and microbial metabolites
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Silvia W. Gratz, Lorraine Scobbie, Freda M. Farquharson, X. Zhang, Alexandra M. Johnstone, Petra Louis, Wendy R. Russell, J. Filipe, Gary Duncan, W.Y. Zhu, Anthony J. Richardson, and C. L. Fyfe
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Nutrition and Dietetics ,High protein ,Medicine (miscellaneous) ,Food science ,Biology - Published
- 2020
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37. Effect of nonmeat, high-protein supplementation on quality of life and clinical outcomes in older residents of care homes: a systematic review and meta-analysis
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Lorna Aucott, Alexandra M. Johnstone, Sarah Alder, Baukje de Roos, Toby O. Smith, Adam L. Gordon, Alison I C Donaldson, and Phyo K. Myint
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0301 basic medicine ,medicine.medical_specialty ,Diet therapy ,media_common.quotation_subject ,MEDLINE ,Declaration ,Nutritional Status ,Medicine (miscellaneous) ,030209 endocrinology & metabolism ,Residential Facilities ,03 medical and health sciences ,Presentation ,0302 clinical medicine ,Quality of life (healthcare) ,Nursing ,medicine ,Humans ,Aged ,Randomized Controlled Trials as Topic ,media_common ,Geriatrics ,030109 nutrition & dietetics ,Nutrition and Dietetics ,Disclaimer ,Health services research ,Dietary Supplements ,Quality of Life ,Dietary Proteins ,Psychology - Abstract
Context: Care home residents are at risk of malnutrition owing to reduced food intake, anabolic resistance in aging muscle, and a high prevalence of medical morbidity and functional dependency. There has been limited consensus regarding the effectiveness of a high-protein diet on quality of life or clinical outcomes in care home residents. Objective: The aim of this review was to evaluate the effectiveness of nonmeat, high-protein supplementation on health-related quality of life (HRQOL) and relevant clinical and nutritional outcomes in older people in a care home setting. Data sources: The following databases were searched (to February 2018) for randomized controlled trials: Embase, AMED, CINAHL, MEDLINE, the Cochrane Central Registry of Controlled Trials, OpenGrey, clinicaltrials.gov, the WHO International Clinical Trials Registry Platform, the ISRCTN registry, and the NIHR Clinical Research Network Portfolio. Study selection: Trials were selected if they assessed a nonmeat, high-protein dietary intervention provided to care home residents who were aged 65 years or older. Data extraction: Data from included trials were extracted if they assessed care home residents aged 65 years or older and compared those residents who received protein supplementation with those who did not. Trial quality was assessed using the Cochrane risk-of-bias tool. Meta-analysis was undertaken when appropriate. Results: Seventeen studies with 1246 participants fulfilled the inclusion criteria. All studies were of low or moderate quality. There was no evidence of improved HRQOL when the Short Form 36 (SF-36) was used to assess outcomes (standardized mean difference [SMD] = −0.10; 95%CI, −0.51 to 0.31; P = 0.62), although significant improvement was seen in the 1 trial that used the EQ-5D instrument (SMD = 2.58; 95%CI, 2.05–3.10; P Conclusion: Nonmeat, high-protein oral supplements can improve markers of nutritional status in care home residents. However, there is insufficient high-quality evidence to determine the effect of such supplements on HRQOL in older adults in care homes.
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- 2018
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38. Role of protein in healthy ageing
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Alison I C Donaldson, Baukje de Roos, Phyo K. Myint, and Alexandra M. Johnstone
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0301 basic medicine ,030109 nutrition & dietetics ,business.industry ,media_common.quotation_subject ,Physiology ,Appetite ,Anorexia ,medicine.disease ,Muscle mass ,Reference Daily Intake ,03 medical and health sciences ,Complementary and alternative medicine ,Weight loss ,Ageing ,Sarcopenia ,medicine ,Healthy ageing ,medicine.symptom ,business ,media_common - Abstract
With the global increase in ageing populations, a current and future key challenge is to improve health expectancy. It is well established that normal ageing is associated with a loss of muscle mass (sarcopenia), with concomitant loss of muscle function and increased risk of falls, reduced ability to perform daily tasks and subsequent reduced quality of life. Therefore, a balanced and optimal protein-energy homeostasis is recognised as a major dietary-related determinant of healthy ageing. This short article provides an overview of the current evidence relating to protein intake in older adults. Older adults may benefit from a protein intake above the recommended daily allowance, with an intake of ≥1.2 g/kg/day to help prevent age-related sarcopenia. The failure of older people to adequately regulate food and nutrient intake results in weight loss, and such changes have been termed the anorexia of ageing and have been attributed to multiple factors affecting the satiety cascade. The quality and timing of protein supplementation in addition to quantity is very important. To improve muscle protein synthesis, pulse feeding may be more effective than bolus feeding, but further evidence is needed. Key foci of ongoing research should be to provide robust evidence from trials in older adults to help define the optimum type and timing of dietary protein supplements.
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- 2018
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39. Biological and psychological mediators of the relationships between fat mass, fat-free mass and energy intake
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Stephen Whybrow, Cristiana Duarte, R. James Stubbs, Graham W. Horgan, Graham Finlayson, Catherine Gibbons, John E. Blundell, Mark Hopkins, and Alexandra M. Johnstone
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medicine.medical_specialty ,Nutrition and Dietetics ,business.industry ,Cross-sectional study ,Endocrinology, Diabetes and Metabolism ,Leptin ,Insulin ,medicine.medical_treatment ,Medicine (miscellaneous) ,030209 endocrinology & metabolism ,medicine.disease ,Fat mass ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Insulin resistance ,Internal medicine ,Heart rate ,Basal metabolic rate ,medicine ,Plethysmograph ,030212 general & internal medicine ,business - Abstract
While recent studies in humans indicate that fat-free mass (FFM) is closely associated with energy intake (EI) when in energy balance, associations between fat mass (FM) and EI are inconsistent. The present study used a cross-sectional design to examine the indirect and direct effects of FFM, FM and resting metabolic rate (RMR) on EI in individuals at or close to energy balance. Data for 242 individuals (114 males; 128 females; BMI = 25.7 ± 4.9 kg/m2) were collated from the non-intervention baseline conditions of five studies employing common measures of body composition (air-displacement plethysmography), RMR (indirect calorimetry) and psychometric measures of eating behaviours (Dutch Eating Behaviour Questionnaire). Daily EI (weighed dietary records) and energy expenditure (flex heart rate) were measured for 6–7 days. Sub-analyses were conducted in 71 individuals who had additional measures of body composition (dual-energy X-ray absorptiometry) and fasting glucose, insulin and leptin. After adjusting for age, sex and study, linear regression and mediation analyses indicated that the effect of FFM on EI was mediated by RMR (P
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- 2018
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40. Dietary carbohydrate rather than protein intake drives colonic microbial fermentation during weight loss
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Silvia W. Gratz, Lorraine Scobbie, Gerald E. Lobley, C. L. Fyfe, Anthony J. Richardson, S Hazim, Wendy R. Russell, Grietje Holtrop, and Alexandra M. Johnstone
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Adult ,Male ,0301 basic medicine ,Colon ,Medicine (miscellaneous) ,030209 endocrinology & metabolism ,Butyrate ,Diet, Carbohydrate-Restricted ,Feces ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Weight loss ,Weight Loss ,Dietary Carbohydrates ,medicine ,Metabolome ,Humans ,Food science ,Aged ,Cross-Over Studies ,030109 nutrition & dietetics ,Nutrition and Dietetics ,Chemistry ,Dietary fibre ,Original Contribution ,Ferulic acid ,Middle Aged ,Overweight ,Carbohydrate ,Body Weight Maintenance ,Gastrointestinal Microbiome ,Fermentation ,Basal metabolic rate ,Diet, High-Protein ,Red meat ,Amino acids ,Dietary Proteins ,medicine.symptom ,Faecal metabolome - Abstract
Purpose High protein weight loss diets are effective in aiding body weight management. However, high protein and low carbohydrate intakes can alter colonic fermentation profiles in humans and may impact on colonic health. This study aims to identify the most important dietary contributors to colonic fermentation during diet-controlled weight loss. Methods Overweight or obese male volunteers (n = 18) consumed a body weight maintenance diet (fed at 1.5× basic metabolic rate, BMR) followed by three weight loss diets (fed at 1× BMR) for 10 days each in a cross-over design. Weight loss diets were designed as normal protein (NPWL, 15% of energy from protein, 55% from carbohydrate), normal protein enriched with free amino acids and moderate amounts of carbohydrate (NPAAWL, 15% of energy from protein, 15% from free AA, 40% from carbohydrate) or high protein containing moderate amounts of carbohydrate (HPWL, 30% of energy from protein, 40% from carbohydrate). Faecal samples collected at the end of each diet period were profiled for dietary metabolites using LC–MS/MS. Results This study shows that the NPWL diet only induced very minor changes in the faecal metabolome, whereas NPAAWL and HPWL diets decreased carbohydrate-related metabolites (butyrate, ferulic acid) and increased protein-related metabolites. Most faecal metabolites were correlated with dietary carbohydrate and not protein intake. Conclusion This study demonstrates that dietary carbohydrate is the main driver of colonic fermentation in humans and that a balance between dietary carbohydrate and protein should be maintained when designing safe, effective and healthy weight loss diets. Electronic supplementary material The online version of this article (10.1007/s00394-018-1629-x) contains supplementary material, which is available to authorised users.
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- 2018
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41. Food additives: Assessing the impact of exposure to permitted emulsifiers on bowel and metabolic health - introducing the FADiets study
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Katie A. Lloyd, Barry J. Campbell, Alan W. Walker, Jonathan M. Rhodes, D. Partridge, and Alexandra M. Johnstone
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0301 basic medicine ,food.ingredient ,emulsifiers ,Medicine (miscellaneous) ,030209 endocrinology & metabolism ,Disease ,Type 2 diabetes ,intestinal health and inflammation ,Gut flora ,Lecithin ,metabolic syndrome ,03 medical and health sciences ,0302 clinical medicine ,food ,In vivo ,medicine ,bacterial translocation ,Food science ,030109 nutrition & dietetics ,Nutrition and Dietetics ,biology ,gut microbiota ,business.industry ,Food additive ,medicine.disease ,biology.organism_classification ,Intestinal epithelium ,Emerging Research ,food additives ,Metabolic syndrome ,business - Abstract
Emulsifiers are common components of processed foods consumed as part of a Western diet. Emerging in vitro cell‐line culture, mouse model and human intestinal tissue explant studies have all suggested that very low concentrations of the food emulsifier polysorbate 80 may cause bacterial translocation across the intestinal epithelium, intestinal inflammation and metabolic syndrome. This raises the possibility that dietary emulsifiers might be factors in conditions such as coronary artery disease, type 2 diabetes and Crohn's disease. The potential mechanism behind the observed effects of this emulsifier is uncertain but may be mediated via changes in the gut microbiota or by increased bacterial translocation, or both. It is also unknown whether these effects are generalisable across all emulsifiers and detergents, including perhaps the natural emulsifier lecithin or even conjugated bile acids, particularly if the latter escape reabsorption and pass through to the distal ileum or colon. A major objective of the Medical Research Council (MRC)‐funded Mechanistic Nutrition in Health (MECNUT) Emulsifier project is therefore to investigate the underlying mechanisms and effects of a range of synthetic and natural emulsifiers and detergents in vitro and in vivo, and to determine the effects of a commonly consumed emulsifier (soya lecithin) on gut and metabolic health through a controlled dietary intervention study in healthy human volunteers – the FADiets study. This report provides an overview of the relevant literature, discussing the impact of emulsifiers and other additives on intestinal and metabolic health, and gives an overview of the studies being undertaken as part of the MECNUT Emulsifier project.
- Published
- 2019
42. Protein Valuation in Food Choice Is Positively Associated with Lean Mass in Older Adults
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Emma J. Stevenson, Elizabeth A. Williams, Alexandra M. Johnstone, Sophie Austin, Bernard M. Corfe, Mark A. Green, Charlotte Buckley, and Jeffrey M. Brunstrom
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Adult ,Male ,Sarcopenia ,Calorie ,030309 nutrition & dietetics ,Ingestive Behavior and Neurosciences ,Medicine (miscellaneous) ,030209 endocrinology & metabolism ,food choice ,Satiation ,Logistic regression ,Choice Behavior ,Body Mass Index ,03 medical and health sciences ,Food Preferences ,Young Adult ,0302 clinical medicine ,lean mass ,Food choice ,Medicine ,Humans ,Mass index ,Original Research Article ,Valuation (finance) ,Aged ,2. Zero hunger ,Aged, 80 and over ,0303 health sciences ,Nutrition and Dietetics ,business.industry ,aging ,Nutrients ,Middle Aged ,medicine.disease ,fat-free mass index ,protein valuation ,Ageing ,Lean body mass ,Body Composition ,Female ,Perception ,Dietary Proteins ,Diet, Healthy ,business ,Energy Intake ,Nutritive Value ,Demography - Abstract
Background Calorie for calorie, protein is more satiating than carbohydrate or fat. However, it remains unclear whether humans perceive calories derived from these macronutrients equally and whether lean mass is associated with a tendency to “value” protein when dietary decisions are made. Objectives This study aimed to determine the test-retest reliability of a novel method for quantifying macronutrient valuations in human volunteers and to determine whether “protein valuation” is associated with a higher fat-free mass index (FFMI) in older adults. Methods A 2-alternative, forced-choice task in which 25 foods were compared in 300 trials was undertaken in 2 studies. In study 1, participants (age range 19–71 y, n = 92) attended 2 test sessions, spaced 1 wk apart. In study 2, older adults (age range 40–85 y; n = 91) completed the food-choice task and assessed the test foods for liking, expected satiety, and perceived healthiness. Body composition and habitual protein intake were assessed in both studies. Data were analyzed through the use of individual binomial logistic regressions and multilevel binomial logistic regressions. Results In study 1, measures of macronutrient valuation showed excellent test-retest reliability; responses in the forced-choice task were highly correlated (week 1 compared with week 2; protein, r = 0.83, P < 0.001; carbohydrate, r = 0.90, P < 0.001; fat, r = 0.90, P < 0.001). Calorie for calorie, protein and carbohydrate were stronger predictors of choice than fat (P < 0.001). In study 2, protein was a stronger predictor than both carbohydrate (P = 0.039) and fat (P = 0.003), and a positive interaction was observed between protein valuation and FFMI (OR = 1.64; 95% CI: 1.38, 1.95; P < 0.001). This was the case after controlling for age, gender, liking for foods, and habitual protein consumption. Conclusions Together, these findings demonstrate that adult humans value calories derived from protein, carbohydrate, and fat differently, and that the tendency to value protein is associated with greater lean mass in older adults.
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- 2019
43. Nudging, formulating new products, and the lifecourse: A qualitative assessment of the viability of three methods for reducing Scottish meat consumption for health, ethical, and environmental reasons
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Alexandra M. Johnstone, David McBey, and David Watts
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0301 basic medicine ,Adult ,Male ,Health Knowledge, Attitudes, Practice ,Meat ,Adolescent ,Consumer choice ,030209 endocrinology & metabolism ,Health Promotion ,Environment ,Choice Behavior ,03 medical and health sciences ,Food Preferences ,Young Adult ,0302 clinical medicine ,Sustainable consumption ,Humans ,General Psychology ,Consumer behaviour ,Aged ,Consumption (economics) ,Aged, 80 and over ,Government ,030109 nutrition & dietetics ,Nutrition and Dietetics ,Public economics ,Plant based ,Consumer Behavior ,Focus Groups ,Middle Aged ,Diet ,Scotland ,Female ,Plants, Edible - Abstract
Most governmental initiatives designed to improve dietary and planetary health have adopted a light-touch informing approach. However, it may be necessary to consider more direct measures that go beyond simply informing the public if the current high levels of meat consumption in Scotland are to be addressed. This paper considers three possible avenues through which more sustainable meat consumption patterns may be promoted: 'nudging', the formulation of new meat-alternative products, and targeting those in particular stages of the lifecourse. Through focus groups held in various locations in Scotland, the perceived viability of these measures was explored. While each measure shows some promise for reducing Scottish meat intake, the complex nature of food choice means that more qualitative research into meat consumption in Scotland is required.
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- 2019
44. Satiety Innovations: Food Products to Assist Consumers with Weight Loss, Evidence on the Role of Satiety in Healthy Eating: Overview and In Vitro Approximation
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Angel M Sanmartín, Alexandra M. Johnstone, Carmen Frontela-Saseta, Jason C.G. Halford, Joanne A. Harrold, Massimo Marzorati, Rubén López-Nicolás, Lia Scarabottolo, and Gaspar Ros-Berruezo
- Subjects
0301 basic medicine ,media_common.quotation_subject ,Calorie restriction ,030209 endocrinology & metabolism ,Healthy eating ,Food technology ,Satiation ,Overweight ,Eating ,03 medical and health sciences ,0302 clinical medicine ,Weight loss ,Weight Loss ,medicine ,Animals ,Humans ,media_common ,030109 nutrition & dietetics ,business.industry ,Product testing ,Appetite ,General Medicine ,medicine.disease ,Obesity ,Biotechnology ,Food ,Diet, Healthy ,Safety ,medicine.symptom ,business ,Psychology - Abstract
The prevalence of overweight and obesity is increasing globally, driven by the availability of energy-dense palatable foods. Most dietary strategies fail because of hunger generated by calorie restriction, and interventions that specifically control hunger and/or promote fullness may aid success. Current consumers have a limited choice of satiety-enhancing products with proven health benefits, and innovative ways to produce new foods (as structural modification) to enhance satiety/satiation may provide new opportunities. However, this potential is hindered by the cost of product testing. Within the SATIN-SATiety INnovation project-an in vitro platform has been developed to offer a cost-effective means of assessing the potential satiation/satiety effect of novel foods. This combines in vitro technologies to assess changes in colonic bacteria metabolism, appetite hormone release and the stability and bioavailability of active compounds in the new products/ingredients. This article provides a brief review of nutrients for which an impact on short-term appetite regulation has been demonstrated, and a summary of the changes to food structure which can be used to produce a change in appetite expression. Furthermore, the SATIN in vitro platform is discussed as a means of assessing the impact of nutritional and structural manipulations on appetite.
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- 2016
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45. Exploring Health-Promoting Attributes of Plant Proteins as a Functional Ingredient for the Food Sector: A Systematic Review of Human Interventional Studies
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Graham W. Horgan, Marta Lonnie, Madeleine Myers, Wendy R. Russell, Ieva Laurie, and Alexandra M. Johnstone
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Blood Glucose ,Male ,0301 basic medicine ,muscle ,Appetite ,Blood lipids ,Review ,Plant Proteins, Dietary ,0302 clinical medicine ,plant protein ,Functional Food ,Weight loss ,Food science ,Randomized Controlled Trials as Topic ,media_common ,Nutrition and Dietetics ,diabetes ,cardiovascular ,Food Ingredients ,blood pressure ,food and beverages ,Postprandial Period ,Systematic review ,Plant protein ,Red meat ,Female ,Diet, Healthy ,medicine.symptom ,lcsh:Nutrition. Foods and food supply ,Adult ,sustainable protein ,media_common.quotation_subject ,lcsh:TX341-641 ,030209 endocrinology & metabolism ,Satiation ,Biology ,Young Adult ,03 medical and health sciences ,dietary protein ,metabolic ,medicine ,Humans ,Muscle, Skeletal ,Glycemic ,030109 nutrition & dietetics ,Body Weight ,weight loss ,Food Science ,Plant Sources - Abstract
The potential beneficial effects of plant-based diets on human health have been extensively studied. However, the evidence regarding the health effects of extracted plant-based proteins as functional ingredients, other than soya, is scarce. The aim of this review was to compile evidence on the effects of extracted protein from a wide range of traditional and novel plant sources on glycemic responses, appetite, body weight, metabolic, cardiovascular and muscle health. A comprehensive search of PubMed, EMBASE and The Cochrane Central Register of Controlled Trials (CENTRAL) was conducted through 23 and 27 March 2020 for randomized controlled trials that featured any of the following 18 plant protein sources: alfalfa, duckweed, buckwheat, chickpea, fava bean, hemp, lentil, lupin, mushroom, oat, pea, potato, pumpkin, quinoa, rapeseed, rice, sacha inchi, sunflower. Only interventions that investigated concentrated, isolated or hydrolysed forms of dietary protein were included. Searched health outcome measures were: change in blood glucose, insulin, satiety hormones concentration, subjective assessment of appetite/satiety, change in blood lipids concentration, blood pressure, body weight and muscle health parameters. Acute and sub-chronic studies were considered for inclusion. Applying the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) approach we identified 1190 records. Twenty-six studies met the inclusion criteria. Plant protein sources used in interventions were most often pea (n = 16), followed by lupin (n = 4), fava bean (n = 2), rice (n = 2), oat (n = 2), hemp (n = 2) and lentil (n = 1). Satiety and postprandial glycemic response were the most frequently reported health outcomes (n = 18), followed by blood lipids (n = 6), muscle health (n = 5), body weight (n = 5) and blood pressure (n = 4). No studies on the remaining plant proteins in the extracted form were identified through the search. Most studies confirmed the health-promoting effect of identified extracted plant protein sources across glycemic, appetite, cardiovascular and muscular outcomes when compared to baseline or non-protein control. However, the current evidence is still not sufficient to formulate explicit dietary recommendations. In general, the effects of plant protein were comparable (but not superior) to protein originating from animals. This is still a promising finding, suggesting that the desired health effects can be achieved with more sustainable, plant alternatives. More methodologically homogenous research is needed to formulate and validate evidence-based health claims for plant protein ingredients. The relevance of these findings are discussed for the food sector with supporting market trends.
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- 2020
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46. Care Home Research: Future Challenges and Opportunities
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Alison I C Donaldson and Alexandra M. Johnstone
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Aging ,Focus (computing) ,Health (social science) ,030214 geriatrics ,business.industry ,Care homes ,Public relations ,lcsh:Geriatrics ,03 medical and health sciences ,lcsh:RC952-954.6 ,Editorial ,0302 clinical medicine ,n/a ,Medicine ,030212 general & internal medicine ,Geriatrics and Gerontology ,business ,Gerontology - Abstract
The historical view of care homes as isolated communities is fading, with a new strong focus on offering person-centred care for residents that keeps them integrated in their community [...]
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- 2018
47. Optimising Nutrition and Hydration in Care Homes—Getting It Right in Person Rather than in Policy
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Phyo K. Myint, Alison I C Donaldson, and Alexandra M. Johnstone
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0301 basic medicine ,Gerontology ,Aging ,Health (social science) ,Psychological intervention ,frailty ,lcsh:Geriatrics ,03 medical and health sciences ,Quality of life (healthcare) ,Weight loss ,Intervention (counseling) ,Medicine ,care homes ,Window of opportunity ,030109 nutrition & dietetics ,business.industry ,dehydration ,medicine.disease ,Malnutrition ,lcsh:RC952-954.6 ,Editorial ,nutrition ,ageing ,Scale (social sciences) ,Geriatrics and Gerontology ,Element (criminal law) ,medicine.symptom ,business - Abstract
The scoping review by Bunn et al. identifies an important, but often invisible, challenge of malnutrition and specifically sub-optimal hydration and nutrition in the care home environment. Those requiring residential care are generally the frailest members of society, and likely to be affected by the anorexia of ageing: a multifactorial process whereby older people fail to adequately regulate food and nutrient intake resulting in unintentional weight loss. Adequate training of all healthcare professionals to recognise the risk of malnutrition at an early stage is fundamentally important, and the window of opportunity for intervention may be at a much earlier stage than admission to the care home. The specific needs of older adults must be considered in planning interventions with regard to the effects of ageing on physiology, digestion, and absorption of nutrients. Most importantly, we must offer person-centred care which offers residents an element of personal choice in whether or not they wish nutritional intervention, and any intervention offered must have the effect of improving quality of life rather than numbers on a scale.
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- 2018
48. Activity energy expenditure is an independent predictor of energy intake in humans
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R. James Stubbs, Graham Finlayson, Catherine Gibbons, John E. Blundell, Stephen Whybrow, Mark Hopkins, Alexandra M. Johnstone, Cristiana Duarte, Graham W. Horgan, and Kristine Beaulieu
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Adult ,Male ,Endocrinology, Diabetes and Metabolism ,Physical activity ,Medicine (miscellaneous) ,030209 endocrinology & metabolism ,03 medical and health sciences ,0302 clinical medicine ,Animal science ,Linear regression ,Heart rate ,Medicine ,Humans ,030212 general & internal medicine ,Exercise physiology ,Exercise ,Whole-body air displacement plethysmography ,Nutrition and Dietetics ,business.industry ,Middle Aged ,medicine.disease ,Obesity ,Diet ,Cross-Sectional Studies ,Energy expenditure ,Basal metabolic rate ,Body Composition ,Female ,business ,Energy Intake ,Energy Metabolism - Abstract
There is evidence that the energetic demand of metabolically active tissue is associated with day-to-day food intake (EI). However, the extent to which behavioural components of total daily energy expenditure (EE) such as activity energy expenditure (AEE) are also associated with EI is unknown. Therefore, the present study examined the cross-sectional associations between body composition, resting metabolic rate (RMR), AEE and EI. Data for 242 individuals (114 males; 128 females; BMI = 25.7 ± 4.9 kg/m2) were collated from the baseline control conditions of five studies employing common measures of body composition (air displacement plethysmography) and RMR (indirect calorimetry). Daily EI (weighed-dietary records) and EE (FLEX heart rate) were measured over 6–7 days, and AEE was calculated as total daily EE minus RMR. Linear regression indicated that RMR (s = 0.39; P
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- 2018
49. The Big Breakfast Study: Chrono-nutrition influence on energy expenditure and bodyweight
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Peter J. Morgan, Alexandra M. Johnstone, Jonathan D. Johnston, and Leonie C. Ruddick-Collins
- Subjects
0301 basic medicine ,Gerontology ,Calorie ,Evening ,Energy balance ,Medicine (miscellaneous) ,030209 endocrinology & metabolism ,Biology ,03 medical and health sciences ,0302 clinical medicine ,Weight loss ,medicine ,Circadian rhythm ,Morning ,Meal ,030109 nutrition & dietetics ,Nutrition and Dietetics ,breakfast ,chrono‐nutrition ,energy balance ,Emerging Research ,meal timing ,circadian rhythms ,ORIGINAL ARTICLES ,weight loss ,medicine.symptom ,Thermogenesis - Abstract
A growing body of evidence highlights the importance of the biological clock as a modulator of energy balance and metabolism. Recent studies in humans have shown that ingested calories are apparently utilised more efficiently in the morning than in the evening and this is manifest through improved weight loss, even under iso‐energetic calorie intake. The mechanisms behind this enhanced morning energy metabolism are not yet clear, although it may result from behavioural adaptations or circadian driven variations in physiology and energy metabolism. A major objective of the newly funded Big Breakfast Study therefore is to investigate the mechanistic basis of this amplified morning thermogenesis leading to enhanced weight loss, by exploring behavioural and physiological adaptations in energy expenditure alongside the underlying circadian biology. This report briefly discusses the current research linking meal timing, circadian rhythms and metabolism; highlights the research gaps; and provides an overview of the studies being undertaken as part of the Medical Research Council‐funded Big Breakfast Study.
- Published
- 2018
50. Effects of hunger state on the brain responses to food cues across the life span
- Author
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Max A. Viergever, Angeliki Giannopoulou, William Buosi, Paul A.M. Smeets, Lisette Charbonnier, Odysseas Androutsos, Yannis Manios, Daniel R Crabtree, F.D. van der Meer, and Alexandra M. Johnstone
- Subjects
Adult ,Male ,Calorie ,Adolescent ,Hunger ,Cognitive Neuroscience ,030209 endocrinology & metabolism ,Overweight ,Satiation ,Developmental psychology ,03 medical and health sciences ,0302 clinical medicine ,Functional neuroimaging ,medicine ,Life Science ,Humans ,Food evaluation ,Reactivity (psychology) ,Prefrontal cortex ,Child ,Sensory Science and Eating Behaviour ,Aged ,VLAG ,Life span ,Functional Neuroimaging ,digestive, oral, and skin physiology ,Age Factors ,Brain ,Middle Aged ,Magnetic Resonance Imaging ,Overconsumption ,Sensoriek en eetgedrag ,Neurology ,Female ,medicine.symptom ,Cues ,Psychology ,030217 neurology & neurosurgery ,Photic Stimulation - Abstract
The abundant exposure to food cues in our environment is one of the main drivers of overconsumption. Food evaluation is important for the regulation of food intake by the brain and it's interaction with hunger state. Children are especially susceptible to food cues. Understanding the mechanisms behind this regulation in healthy individuals across the life span can help to elucidate the mechanisms underlying overconsumption and aid the development of future obesity prevention strategies. Few functional neuroimaging studies have been done in children and elderly. Furthermore, it is unknown how hunger state affects neural food cue reactivity in these groups, since this has not been examined consistently. We examined the effects of hunger state and age on the brain responses to low- and high calorie foods. On two mornings, 122 participants (17 children; 38 teens; 36 adults; 31 elderly) performed a food image viewing task while being scanned using fMRI, either fasted or sated. Hunger induced greater activation during high versus low calorie food image viewing than satiety in the bilateral dorsomedial (dmPFC) and in the right dorsolateral prefrontal cortex (dlPFC) across all age groups. There was no significant main effect of age group on high versus low calorie food image viewing and no interaction between age group and hunger state. The greater activation of the dlPFC across all age groups during high calorie food image viewing in a fasted state might reflect increased inhibitory control in response to these foods. This may underlie the ability to resist overconsumption of high calorie foods. Furthermore, increased medial prefrontal cortex activation during hunger might reflect increased reward value of high calorie foods, which declines with satiation. Further studies are needed to better understand these results. Notably, overweight and obese individuals should be included to examine whether these responses are altered by weight status across the life span.
- Published
- 2018
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