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Type 2 diabetes (T2D) and CVD are major causes of mortality and chronic morbidity. Whilst mortality from CVD has decreased they remain the largest cause of death in Europe and the prevalence of T2D is increasing rapidly. A consistent component of public health advice is to reduce intake of SFA to reduce CVD in particular, which implies limiting dairy food consumption. The prospective studies and randomised controlled trials included in this review show that for dairy foods at least, SFA are not consistently associated with CVD or T2D risk. For CVD the association with dairy foods is generally neutral despite dairy foods being the major source of SFA in many diets. This creates considerable doubt, at least for dairy foods, concerning the validity of the traditional diet-heart hypothesis which positively relates SFA intake to increased serum LDL-cholesterol and subsequent increased CVD. There is now emerging evidence to explain this which is highly relevant to dairy foods. These include the potentially counterbalancing effect of SFA-stimulated HDL-cholesterol and specific food matrix factors. In addition, SFA are associated with the less atherogenic large buoyant LDL particles and possible counterbalancing hypotensive effects of dairy proteins. Overall, dairy foods have either a neutral or beneficial association with CVD and T2D. Beneficial associations are seen for blood pressure and the reduced T2D risk linked to yoghurt consumption, a subject that needs urgent attention given the sharp rise in T2D prevalence in many countries.

Background and aims: Higher protein (HP) diets may lead to lower cardiometabolic risk, compared to lower\ud protein (LP) diets. This systematic review and meta-analysis aims to investigate the effects of HP versus LP diets\ud on cardiometabolic risk factors in adults, using the totality of the current evidence from randomised controlled\ud trials (RCTs).\ud Methods: Systematic searches were conducted in electronic databases, up to November 2020. Random effects\ud meta-analyses were conducted to pool the standardised mean differences (SMD) and 95% confidence intervals\ud (CI). The main outcomes were weight loss, body mass index (BMI), waist circumference, fat mass, systolic and\ud diastolic BP, total cholesterol, HDL-and LDL-cholesterol, triacylglycerol, fasting glucose and insulin, and glycated\ud haemoglobin.\ud Results: Fifty-seven articles reporting on 54 RCTs were included, involving 4344 participants (65% female, mean\ud age: 46 (SD 10) years, mean BMI: 33 (SD 3) kg/m2\ud ), with a mean study duration of 18 weeks (range: 4 to 156\ud weeks). Compared to LP diets (range protein (E%):10–23%), HP diets (range protein (E%): 20–45%) led to more\ud weight loss (SMD -0.13, 95% CI: -0.23, − 0.03), greater reductions in fat mass (SMD -0.14, 95% CI: -0.24, − 0.04),\ud systolic BP (SMD -0.12, 95% CI: -0.21, − 0.02), total cholesterol (SMD -0.11, 95% CI: -0.19, − 0.02), triacylglycerol (SMD -0.22, 95% CI: -0.30, − 0.14) and insulin (SMD -0.12, 95% CI: -0.22, − 0.03). No significant\ud differences were observed for the other outcomes.\ud Conclusions: Higher protein diets showed small, but favourable effects on weight loss, fat mass loss, systolic blood\ud pressure, some lipid outcomes and insulin, compared to lower protein diets.

Sixteen multiparous Holstein cows in four blocks of 4 x 4 Latin square over 4-week experimental periods were used to study the effects of seaweed (Saccharina latissima) supplement (with/without) and protein source (rapeseed meal (RSM)/wheat distiller's grain (WDG)) on milk mineral concentrations. Dietary treatments did not affect milk production and basic composition. Feeding seaweed slightly decreased milk Ca and Cu concentrations; whilst increased (by 3.3-fold) milk iodine (I) concentration, due to a higher dietary I supply. Substitution of WDG with RSM increased feed-to-milk transfer of Ca, Na, and Se and decreased that of Mg, P, Fe, and Mn; but only reduced milk Mn and I concentrations (the latter by 27 % as a potential result of increased glucosinolate intake). Seaweed supplement can improve milk I content when cows' I supply/availability is limited, but care should be taken to avoid excess milk I contents that may pose nutritional risks for young children.

The prevalence of type 2 diabetes (T2D) has increased rapidly. Adopting a heathy diet is suggested as one of the effective behaviors to prevent or delay onset of T2D. Dairy consumption has been recommended as part of a healthy diet, but there remains uncertainty in both the scientific community and the public about the effect of different dairy products on T2D risk. In a recent workshop, the evidence on dairy products and T2D risk was presented and discussed by a group of experts. The main conclusions from the workshop are presented in this position paper and are as follows. 1) Available evidence from large prospective cohort studies and limited randomized controlled trials (RCTs) suggests that total dairy consumption has a neutral or moderately beneficial effect on T2D risk. 2) Increasing evidence from prospective cohort studies indicates that yogurt is most strongly associated with a lower T2D risk, but evidence from RCTs is scarce. 3) Fatty acids from dairy (medium-chain, odd, and very long-chain SFAs as well as trans-palmitoleic acid) are associated with lower T2D risk and improved metabolic health, but more research is needed on studies that explore cause and effect relations to exclude the possibility that the dairy fatty acids simply serve as markers of overall dairy consumption. 4) The food matrix can be a stronger determinant of health effects than SFA content. This review further identifies research gaps in the existing knowledge and highlights key research questions that need to be addressed to better understand the impact of dairy consumption on future T2D risk.

Many health benefits of millets (defined broadly to also include sorghum) have been advocated, including their roles in managing and preventing diabetes; however, the effects of millets on hyperlipidemia (high lipid levels) have been underrecognized. A systematic review and meta-analysis were conducted to collate available evidence of the impacts of millets consumption on lipid profile, namely total cholesterol (TC), triacylglycerol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and very-low–density lipoprotein cholesterol (VLDL-C). The results from 19 studies showed that the consumption of millets for periods as short as 21 days to 4 months reduced levels of TC, triacylglycerol, LDL-C, and VLDL-C (pSystematic Review Registration: The protocol of this systematic review has been registered in the online registration platform called “research registry” with the unique identification number “reviewregistry1123.”

Millets (including sorghum) are known to be highly nutritious besides having a low carbon footprint and the ability to survive in high temperatures with minimal water. Millets are widely recognised as having a low Glycaemic Index (GI) helping to manage diabetes. This systematic review and meta-analyzes across the different types of millets and different forms of processing/cooking collated all evidences. Of the 65 studies that were collected globally, 39 studies with 111 observations were used to analyze GI outcomes and 56 studies were used to analyze fasting, post-prandial glucose level, insulin index and HbA1c outcomes in a meta-analysis. It is evident from the descriptive statistics that the mean GI of millets is 52.7 ± 10.3, which is about 36% lower than in typical staples of milled rice (71.7 ± 14.4) and refined wheat (74.2 ± 14.9). The descriptive, meta and regression analyses revealed that Job's tears, fonio, foxtail, barnyard, and teff were the millets with low mean GI (69). A meta-analysis also showed that all millets had significantly (p < 0.01) lower GI than white rice, refined wheat, standard glucose or white wheat bread except little millet which had inconsistent data. Long term millet consumption lowered fasting and post-prandial blood glucose levels significantly (p < 0.01) by 12 and 15%, respectively, in diabetic subjects. There was a significant reduction in HbA1c level (from 6.65 ± 0.4 to 5.67 ± 0.4%) among pre-diabetic individuals (p < 0.01) who consumed millets for a long period. Minimally processed millets were 30% more effective in lowering GI of a meal compared to milled rice and refined wheat. In conclusion, millets can be beneficial in managing and reducing the risk of developing diabetes and could therefore be used to design appropriate meals for diabetic and pre-diabetic subjects as well as for non-diabetic people for a preventive approach.

Lactating cow diets were supplemented with high oleic acid sunflower oil over two production periods spanning two years, to modify the milk fat, partially replacing saturated fatty acids (SFA) with cis-monounsaturated fatty acids (MUFA). The resulting milk was used for ultra-high temperature (UHT) milk, butter and Cheddar cheese production, and fatty acid profiles were compared with those of conventionally-produced products. Fat from products made with modified milk had lower SFA and higher cis- and trans-MUFA concentrations than that of conventional products. This was consistent over production periods, demonstrating that this food chain approach could be adopted on a wider scale.

Milk is the largest source of iodine in UK diets and earlier studies showed organic summer and winter\ud milk to be significantly lower in iodine than conventional milk. One study also showed UHT milk to have\ud lower iodine concentration. The study on winter and UHT milk was small and accordingly a new study is\ud reported here involving conventional, organic and UHT semi-skimmed milk from four supermarkets over\ud a six-month period in summer and winter in two regions of the UK. The results showed organic milk to be\ud 44% lower in iodine than conventional milk (427 vs. 241 mg/L, P < 0.001) and UHT milk was 27% lower in\ud iodine than conventional milk (427 vs. 314 mg/L, P < 0.001) although the differences tended to be less in\ud the summer. The results indicate that replacement of conventional milk by organic or UHT milk will\ud increase the risk of sub-optimal iodine status especially for pregnant/lactating women.

The ability to synthesise sufficient vitamin D through sunlight in human subjects can be limited. Thus, diet has become an important contributor to vitamin D intake and status; however, there are only a few foods (e.g. egg yolk, oily fish) naturally rich in vitamin D. Therefore, vitamin D-enriched foods via supplementing the animals’ diet with vitamin D or vitamin D fortification of foods have been proposed as strategies to increase vitamin D intake. Evidence that cholecalciferol (vitamin D3) and calcifediol (25(OH)D3) content of eggs, fish and milk increased in response to vitamin D3 supplementation of hens, fish or cows’ diets was identified when vitamin D-enrichment studies were reviewed. However, evidence from supplementation studies with hens showed only dietary 25(OH)D3, not vitamin D3 supplementation, resulted in a pronounced increase of 25(OH)D3 in the eggs. Furthermore, evidence from randomised controlled trials indicated that a 25(OH)D3 oral supplement could be absorbed faster and more efficiently raise serum 25(OH)D concentration compared with vitamin D3 supplementation. Moreover, evidence showed the relative effectiveness of increasing vitamin D status using 25(OH)D3 varied between 3·13 and 7·14 times that of vitamin D3, probably due to the different characteristics of the investigated subjects or study design. Therefore, vitamin D-enrichment or fortified foods using 25(OH)D3 would appear to have advantages over vitamin D3. Further well-controlled studies are needed to assess the effects of 25(OH)D3 enriched or fortified foods in the general population and clinical patients.

Cancer is a complex group of diseases often with long progression periods. As a result the ability to identify associations between foods and other components of the diet with cancer events is extremely challenging. Inevitably most of the evidence is gathered from long term prospective cohort or case-control studies which are not regarded as a high level of evidence although their value is substantially improved by systematic reviews plus meta-analysis. Over the last 25 years the World Cancer Research Fund (WCRF) and the American Institute for Cancer Research (AICR) have had a joint programme to review and evaluate the published evidence on the relationship between diet, nutrition, physical activity and cancer. This chapter will primarily summarise the latest evidence they have published on the associations between dairy food consumption and cancer risk. Their latest key findings are 1) ‘Consumption of dairy products probably protects against colorectal cancer’, 2) There is ‘Limited-suggestive evidence that dairy products can decrease premenopausal breast cancer risk’, but the post-menopausal situation is less clear and ‘no conclusion was possible’ and 3) ‘For a higher consumption of dairy products, the evidence suggesting an increased risk of prostate cancer is limited’.

OBJECTIVES: Our objective was to conduct a systematic review and meta-analysis of the effects of higher versus lower dietary protein consumption on obesity and diabetes related measures in adults, using the most up-to-date evidence from randomised controlled trials (RCTs). METHODS: A systematic search with predefined keywords was conducted in PubMed, Scopus, and Web of Science up to January 2020 and subsequently updated in November 2020. Adult populations (age range: 23 to 68 years; mean body mass index (BMI): 33 ± 3.3 kg/m(2)) were included and the percentage of men/women was 35%/65%. Data were independently extracted with the use of standard forms in “Covidence” and with double data-entry checks. Random effects meta-analyses were conducted to pool the standardised mean differences (SMD) and 95% confidence intervals (CI). The main study outcomes were weight loss, fat mass, BMI, waist circumference, fasting glucose, fasting insulin and glycated haemoglobin (HbA(1c)). RESULTS: Fifty-seven articles reporting on 54 trials were included, with 2185 and 2159 participants in the higher protein (HP) and lower protein (LP) groups, respectively. The mean daily energy intakes were 1764 ± 455 kcal in the HP group and 1768 ± 462 kcal in the LP group. The percentage of protein, carbohydrate, and total fat of the total daily energy intake (E%) were 28%, 41% and 30% in the HP group and 18%, 54% and 28% in the LP group. Significant effects of the HP compared to LP diets were found for weight loss (pooled SMD −0.13, 95% CI: −0.23, −0.04) and fat mass (pooled SMD −0.14, 95% CI: −0.25, −0.04), with small to moderate heterogeneity. This is equivalent to a greater weight loss of 0.67 kg (95% CI: −1.14, −0.19) and a greater reduction in fat mass of 0.57 kg (95% CI: −0.95, −0.19) after the HP compared to LP diets. No significant differences were found for the other study outcomes. CONCLUSIONS: This meta-analysis of 54 trials showed that higher (28 E%) compared to lower protein diets (18 E%) had small but favourable effects on weight loss and fat mass, which are relevant indicators for the development of obesity and its complications. FUNDING SOURCES: None.

The study reported in this Research Communication compared retail milks’ FA profiles from two neighbouring countries, estimated the potential contributions of these milks and a designer milk (achieved by changing the diet of the dairy cow) to the recommended human dietary intake of FA, and predicted (based on the milk FA profile) methane emission from dairy cows. Retail milks in Estonia and Latvia were purchased from supermarkets monthly for one year. To compare the FA composition of retail milk with designer milk with an increased PUFA content, the bulk milk FA profile from a separate field trial was used. Milk FA concentrations of the two neighbouring countries were affected by state, season and their interaction, while the main influence on all these factors were different feeding practices (grazing availability, forage to concentrate ratio and legume-rich silages vs. maize silages). Three cups (600 mL; fat content 2·5 g/100 g) of Estonian, or Latvian retail milk or designer milk per day contributed more to the recommended intakes of saturated FA (SFA) (42·5, 42·7, 38·7%, respectively) than other FA. Compared to the retail milks, α-linolenic acid estimated intake was almost doubled by designer milk consumption (19·7% of adequate intake) without influencing summed intakes of SFA and trans FA. There were state and seasonal differences in the predicted methane outputs of dairy cattle based on retail milk FA. Although the FA profiles of retail milks in the two neighbouring countries were affected by state and season, an appreciable increase in human dietary intakes of beneficial fatty acids from milk, and concomitant reduction in methane emissions from dairy cows, can be achieved only by targeted feeding.

This study investigated the effect of UK dairy production system, month, and their interaction, on retail milk fatty acid (FA) profile throughout the year. Milk samples (n = 120) from four conventional (CON), four organic (ORG) and two free-range (FR) brands were collected monthly. ORG milk had more nutritionally-desirable polyunsaturated FA, including rumenic acid and the omega-3 PUFA α-linolenic, eicosapentaenoic and docosapentaenoic acids, and less of the nutritionally-undesirable palmitic acid. Milk FA profile was similar between FR and CON systems, but FR milk had less saturated FA (SFA) and/or palmitic acid, and/or greater α-linolenic and rumenic acids in certain months within the peak-grazing season. According to the measured milk FA profiles and UK milk fat intakes, milk and dairy products contribute around one-third of the maximum recommended SFA intake. A small increased intake of beneficial PUFA may be expected by consuming ORG milk but human health implications from such differences are unknown.

Foods derived from animals are an important source of nutrients for humans. Concerns have been raised that due to their SFA content, dairy foods may increase the risk of cardiometabolic disease. Prospective studies do not indicate an association between milk consumption and increased disease risk although there are less data for other dairy foods. SFA in dairy products can be partially replaced by cis-MUFA through nutrition of the dairy cow although there are too few human studies to conclude that such modification leads to reduced chronic disease risk. Intakes of LCn-3 FA are sub-optimal in many countries and while foods such as poultry meat can be enriched by inclusion of fish oil in the diet of the birds, fish oil is expensive and has an associated risk that the meat will be oxidatively unstable. Novel sources of LCn-3 FA such as kirll oil, algae, and genetically modified plants may prove to be better candidates for meat enrichment. The value of FA-modified foods cannot be judged by their FA composition alone and there needs to be detailed human intervention studies carried out before judgements concerning improved health value can be made. Practical applications: The amount and FA composition of dietary lipids are known to contribute to the risk of chronic disease in humans which is increasing and becoming very costly to treat. The use of animal nutrition to improve the FA composition of staple foods such as dairy products and poultry meat has considerable potential to reduce chronic risk at population level although judgements must not be based simply on FA composition of the foods.

This study compared fat and fatty acids in cooked retail chicken meat from conventional and organic systems. Fat contents were 1.7, 5.2, 7.1 and 12.9 g/100 g cooked weight in skinless breast, breast with skin, skinless leg and leg with skin respectively, with organic meat containing less fat overall (P < 0.01). Meat was rich in cis-monounsaturated fatty acids, although organic meat contained less than did conventional meat (1850 vs. 2538 mg/100 g; P < 0.001). Organic meat was also lower (P < 0.001) in 18:3 n−3 (115 vs. 180 mg/100 g) and, whilst it contained more (P < 0.001) docosahexaenoic acid (30.9 vs. 13.7 mg/100 g), this was due to the large effect of one supermarket. This system by supermarket interaction suggests that poultry meat labelled as organic is not a guarantee of higher long chain n−3 fatty acids. Overall there were few major differences in fatty acid contents/profiles between organic and conventional meat that were consistent across all supermarkets.

Milk and dairy products are major sources of fat in the human diet, but there are few detailed reports on the fatty acid composition of retail milk, trans fatty acids in particular, and how these change throughout the year. Semi-skimmed milk was collected monthly for one year from five supermarkets and analysed for fatty acid composition. Relative to winter, milk sold in the summer contained lower total saturated fatty acid (SFA; 67 vs 72 g/100g fatty acids) and higher cis-monounsaturated fatty acid (MUFA; 23 vs 21 g/100g fatty acids) and total trans fatty acid (6.5 vs 4.5 g/100g fatty acids) concentrations. Concentrations of most trans-18:1 and -18:2 isomers also exhibited seasonal variation. Results were applied to national dietary intakes, and indicated that monthly variation in the fatty acid composition of milk available at retail has limited influence on total dietary fatty acid consumption by UK adults.

The A1 variant protein of the β-casein family has been implicated in various disease states although much evidence is weak or contradictory. The primary objective was to measure, for the first time, the proportions of the key β-casein variant proteins in UK retail milk over the course of one year. In total, 55 samples of semi-skimmed milk were purchased from five supermarkets over the course of a year and the proportions of the A1, A2, B and C casein variant proteins were measured, using high resolution HPLC–MS. The results showed that β-casein in UK retail milk comprises approximately 0.58, 0.31, 0.07 and 0.03 A2, A1, B and C protein variants, respectively. The proportion of A2 is higher than some early studies would predict although the reasons for this and any implications for health are unclear.

Epidemiological studies show an inverse association between dairy consumption and blood pressure (BP) but there are few data on the postprandial effects of milk proteins. This study examined their effects, compared to maltodextrin, on postprandial BP and other CVD risk markers in volunteers with mild and pre-hypertension over an 8 h period. In this double-blinded, randomised, cross-over, controlled study 27 adults ingested a high-fat, isoenergetic breakfast and lunch with 28 g whey protein, 28 g Ca-caseinate or 27 g maltodextrin. Whey protein reduced systolic BP compared with Ca-caseinate (−15.2 ± 13.6 mmHg) and maltodextrin (−23.4 ± 10.5 mmHg) up to 5 h post-ingestion. There was an improvement in arterial stiffness after whey protein compared with maltodextrin (incremental Area Under the Curve- iAUC0–8h: +14.4 ± 6.2%). Despite similar glucose levels after both whey protein and Ca-caseinate, whey protein induced a higher insulin response than Ca-caseinate (iAUC0–8h: +219.5 ± 54.6 pmol/L). Ca-caseinate induced less suppression of non-esterified fatty acids than whey protein (iAUC0–5h: −58.9 ± 135.5 μmol/L) and maltodextrin (iAUC0–5h: −106.9 ± 89.4 μmol/L) and induced a smaller postprandial triacylglycerol response than whey protein (iAUC0–8h: −1.68 ± 0.6 mmol/L). Milk proteins co-ingestion with high-fat meals may have the potential to maintain or improve CVD risk factors.

Background: Few prospective studies have examined dairy fat in relation to cardiovascular disease (CVD).

Prevalence of type 2 diabetes mellitus (T2DM) is rapidly increasingly and is a key risk for CVD development, now recognised as the leading cause of death globally. Dietary strategies to reduce CVD development include reduction of saturated fat intake. Milk and dairy products are the largest contributors to dietary saturated fats in the UK and reduced consumption is often recommended as a strategy for risk reduction. However, overall evidence from prospective cohort studies does not confirm a detrimental association between dairy product consumption and CVD risk. The present review critically evaluates the current evidence on the association between milk and dairy products and risk of CVD, T2DM and the metabolic syndrome (collectively, cardiometabolic disease). The effects of total and individual dairy foods on cardiometabolic risk factors and new information on the effects of the food matrix on reducing fat digestion are also reviewed. It is concluded that a policy to lower SFA intake by reducing dairy food consumption to reduce cardiometabolic disease risk is likely to have limited or possibly negative effects. There remain many uncertainties, including differential effects of different dairy products and those of differing fat content. Focused and suitably designed and powered studies are needed to provide clearer evidence not only of the mechanisms involved, but how they may be beneficially influenced during milk production and processing.

Although milk consumption is recommended in most dietary guidelines around the world, its contribution to overall diet quality remains a matter of debate in the scientific community as well as in the public domain. This article summarizes the discussion among experts in the field on the place of milk in a balanced healthy diet. The evidence to date suggests at least a neutral effect of milk intake on health outcomes. The possibility that milk intake is simply a marker of diets higher in nutritional quality cannot be ruled out. This review also identifies a number of key research gaps pertaining to the impact of milk consumption on health. These need to be addressed to better inform future dietary guidelines.

Background: Cardiovascular diseases (CVDs) are the greatest cause of death globally, and their reduction is a key public-health target. High blood pressure (BP) affects 1 in 3 people in the United Kingdom, and previous studies have shown that milk consumption is associated with lower BP. Objective: We investigated whether intact milk proteins lower 24-h ambulatory blood pressure (AMBP) and other risk markers of CVD. Design: The trial was a double-blinded, randomized, 3-way–crossover, controlled intervention study. Forty-two participants were randomly assigned to consume 2 × 28 g whey protein/d, 2 × 28 g Ca caseinate/d, or 2 × 27 g maltodextrin (control)/d for 8 wk separated by a 4-wk washout. The effects of these interventions were examined with the use of a linear mixed-model ANOVA. Results: Thirty-eight participants completed the study. Significant reductions in 24-h BP [for systolic blood pressure (SBP): −3.9 mm Hg; for diastolic blood pressure (DBP): −2.5 mm Hg; P = 0.050 for both)] were observed after whey-protein consumption compared with control intake. After whey-protein supplementation compared with control intake, peripheral and central systolic pressures [−5.7 mm Hg (P = 0.007) and −5.4 mm Hg (P = 0.012), respectively] and mean pressures [−3.7 mm Hg (P = 0.025) and −4.0 mm Hg (P = 0.019), respectively] were also lowered. Flow-mediated dilation (FMD) increased significantly after both whey-protein and calcium-caseinate intakes compared with control intake [1.31% (P < 0.001) and 0.83% (P = 0.003), respectively]. Although both whey protein and calcium caseinate significantly lowered total cholesterol [−0.26 mmol/L (P = 0.013) and −0.20 mmol/L (P = 0.042), respectively], only whey protein decreased triacylglycerol (−0.23 mmol/L; P = 0.025) compared with the effect of the control. Soluble intercellular adhesion molecule 1 and soluble vascular cell adhesion molecule 1 were reduced after whey protein consumption (P = 0.011) and after calcium-caseinate consumption (P = 0.039), respectively, compared with after control intake. Conclusions: The consumption of unhydrolyzed milk proteins (56 g/d) for 8 wk improved vascular reactivity, biomarkers of endothelial function, and lipid risk factors. Whey-protein supplementation also lowered 24-h ambulatory SBP and DBP. These results may have important implications for public health. This trial was registered at clinicaltrials.gov as NCT02090842.

The prevalence of cardiometabolic diseases is a significant public health burden worldwide. Emerging evidence supports the inverse association between greater dairy consumption and reduced risk of cardiometabolic diseases. Dairy proteins may have an important role in the favourable impact of dairy on human health such as blood pressure (BP), blood lipid and glucose control. The purpose of this review is to update and critically evaluate the evidence on the impacts of casein and whey protein in relation to metabolic function. Evidence from short-term clinical studies assessing postprandial responses to milk protein ingestion suggests benefits on vascular function independent of BP, as well as improvement in glycaemic homeostasis. Long-term interventions have been less conclusive, with some showing benefits and others indicating a lack of improvement in vascular function. During chronic consumption BP appears to be lowered and both dyslipidaemia and hyperglacaemia seem to be controlled. Limited number of trials investigated the effects of dairy proteins on oxidative stress and inflammation. Although the underlying mechanisms of milk proteins on cardiometabolic homeostasis remains to be elucidated, the most likely mechanism is to improve insulin resistance. The incorporation of meals enriched with dairy protein in the habitual diet may result in the beneficial effects on cardiometabolic health. Nevertheless, future well-designed, controlled studies are needed to investigate the relative effects of both casein and whey protein on BP, vascular function, glucose homeostasis and inflammation.

BACKGROUND: Enriching poultry meat with long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA) can increase low population intakes of LC n-3 PUFA, but fishy taints can spoil reheated meat. This experiment determined the effect of different amounts of LC n-3 PUFA and vitamin E in the broiler diet on the fatty acid composition and sensory characteristics of the breast meat. Ross 308 broilers (120) were randomly allocated to one of five treatments from 21 to 42 days of age. Diets contained (g kg−1) 0, 9 or 18 LC n-3 PUFA (0LC, 9LC, 18LC), and 100, 150 or 200 mg LD--tocopherol acetate kg−1 (E). The five diets were 0LC100E, 9LC100E, 18LC100E, 18LC150E, 18LC200E, with four pens per diet, except 18LC100E (eight pens). Breast meat was analysed for fatty acids (uncooked) and sensory analysis by R-index (reheated). RESULTS: LC n-3 PUFA content (mg kg−1 meat) was 514 (0LC100E) and 2236 (9LC and 18LC). Compared with 0LC100E, meat from 18LC100E and 18LC150E tasted significantly different, while 23% of panellists detected fishy taints in 9LC100E and 18LC200E. CONCLUSION: Chicken meat can be enriched with nutritionally meaningful amounts of LC n-3 PUFA, but > 100 mg dl--tocopherol acetate kg−1 broiler diet is needed to protect reheated meat from oxidative deterioration. Copyright © 2010 Society of Chemical Industry

The health effects of milk and dairy food consumption would best be determined in randomised controlled trials. No adequately powered trial has been reported and none is likely because of the numbers required. The best evidence comes, therefore, from prospective cohort studies with disease events and death as outcomes. Medline was searched for prospective studies of dairy food consumption and incident vascular disease and Type 2 diabetes, based on representative population samples. Reports in which evaluation was in incident disease or death were selected. Meta-analyses of the adjusted estimates of relative risk for disease outcomes in these reports were conducted. Relevant case-control retrospective studies were also identified and the results are summarised in this article. Meta-analyses suggest a reduction in risk in the subjects with the highest dairy consumption relative to those with the lowest intake: 0.87 (0.77, 0.98) for all-cause deaths, 0.92 (0.80, 0.99) for ischaemic heart disease, 0.79 (0.68, 0.91) for stroke and 0.85 (0.75, 0.96) for incident diabetes. The number of cohort studies which give evidence on individual dairy food items is very small, but, again, there is no convincing evidence of harm from consumption of the separate food items. In conclusion, there appears to be an enormous mis-match between the evidence from long-term prospective studies and perceptions of harm from the consumption of dairy food items.

With the wide acceptance of the long-chain (LC)n-3 PUFA EPA and DHA as important nutrients playing a role in the amelioration of certain diseases, efforts to understand factors affecting intakes of these fatty acids along with potential strategies to increase them are vital. Widespread aversion to oil-rich fish, the richest natural source of EPA and DHA, highlights both the highly suboptimal current intakes in males and females across all age-groups and the critical need for an alternative supply of EPA and DHA. Poultry meat is a popular and versatile food eaten in large quantities relative to other meats and is open to increased LCn-3 PUFA content through manipulation of the chicken's diet to modify fatty acid deposition and therefore lipid composition of the edible tissues. It is therefore seen as a favourable prototype food for increasing human dietary supply of LCn-3 PUFA. Enrichment of chicken breast and leg tissue is well established using fish oil or fishmeal, but concerns about sustainability have led to recent consideration of algal biomass as an alternative source of LCn-3 PUFA. Further advances have also been made in the quality of the resulting meat, including achieving acceptable flavour and storage properties as well as understanding the impact of cooking on the retention of fatty acids. Based on these considerations it may be concluded that EPA- and DHA-enriched poultry meat has a very positive potential future in the food chain.

The beneficial effects of long-chain (C chain ≥20)n-3 PUFA are well documented and, overall, increased intake reduces risk of CVD. Recent evidence also points to a role in reducing age-related decline in cognitive function. The two key fatty acids are EPA (20:5) and DHA (22:6), with current UK recommendation for adults being 450 mg EPA+DHA/d. Whilst some EPA and DHA can be synthesisedin vivofrom α-linolenic acid, recent data indicate this source to be very limited, suggesting that EPA and DHA should be classified as dietary essentials. In many parts of Europe the daily intake of EPA+DHA by adults and especially young adults (18–24 years) is

Since estimated dietary selenium intake in the UK has declined steadily from around 60 mug day(-1) in 1975 to 34 mug day(-1) in 1997, there is a need to increase selenium intake from staple foods such as milk and milk products. An experiment was therefore done to investigate the relationship between dietary source and concentration of selenium and the selenium content of bovine milk. In a 3 x 3 factorial design, 90 mid-lactation Holstein dairy cows were supplemented over 8 weeks with either sodium selenite (S), a chelated selenium product (Selenium Metasolate(TM)) (C) or a selenium yeast (Sel-plex(TM)) (Y) at three different dietary inclusion levels of 0.38 (L), 0.76 (M) and 1.14 (H) mg kg(-1) dry matter (DM). Significant increases in milk selenium concentration were observed for all three sources with increasing inclusion level in the diet, but Y gave a much greater response (up to +65 mug l(-1)) than the other two sources of selenium (S and C up to +4 and +6 mug l(-1) respectively). The Y source also resulted in a substantially higher apparent efficiency of transfer of selenium from diet to milk than S or C. Feeding Y at the lowest dietary concentration, and thus within the maximum level permitted under EU regulations, resulted in milk with a selenium concentration of 28 mug l(-1). If the selenium concentration of milk in the UK was increased to this value, it would, at current consumption rates, provide an extra 8.7 mug selenium day(-1), or 11 and 14% of daily recommended national intake for men and women respectively. (C) 2004 Society of Chemical Industry.

The potential to increase the concentrations of n-3 polyunsaturated fatty acids (PUFAs) in milk fat was investigated by studying the effects of feeding a xylose-treated, whole cracked linseed supplement (rich in α-linolenic acid) to dairy cows. Also the effect of increasing the dietary intake of vitamin E on the vitamin E status of milk was investigated. The effect of pasteurisation on milk fatty acid composition was also examined. Using a 3 × 2 factorial design, a total of 60 Holstein dairy cows were fed a total mixed ration based on grass silage supplemented with one of three levels of whole cracked linseed (78, 142 or 209 g·kg-1 diet dry matter (DM); designated LL, ML or HL, respectively) in combination with one of two levels of additional dietary vitamin E intake (6 or 12 g vitamin E·animal -1 ·day -1 ; designated LE or HE, respectively). Increasing lipid supplementation reduced (P 0.05) of increasing vitamin E intake from 6 to 12 g·animal -1 ·day -1 . The

With the aim of reducing the degree of saturation and increasing the C18:1 cis fatty acid content of milk fat, the effects of feeding high levels of whole cracked rapeseed to dairy cows was in- vestigated together with the effect of increasing dietary intake of vitamin E on the vitamin E content of milk. Usin ga3×3f actorial design, 90 Holstein dairy cows were fed one of three levels of whole cracked rapeseed (0 (ZR), 134 (MR) and 270 g·kg -1 diet dry matter (DM) (HR)) in combination with one of three intakes of supplementary vitamin E (0 (ZE), 2 (ME) and 4 g·cow -1 ·d -1 (HE)). Supple- menting with up to almost 2 kg·d -1 of rapeseed oil (diet HR) significantly (P < 0.001) increased C18:1cis in milk fat, from 181 (ZR) to over 400 g·kg -1 (HR) of total milk fatty acids. Concentrations of C18:0, C18:2 and C18:3 fatty acids were also increased (P < 0.001) but by a much lesser degree, and the saturated fatty acids C4:0 to C16:0 decreased substantially. Vitamin E supplementation in- creased (P < 0.01) milk vitamin E concentrations from 1.29 (ZE) to 1.68 mg·kg -1 whole milk (HE). Thus substantial changes in milk fat composition with potentially beneficial effects on human health were achieved and without any adverse effects on milk taste. However, these improvements must be offset against the substantial reductions (P < 0.001) observed in voluntary feed DM consumption (ZR, 20.6; HR, 15.2 kg DM·d -1 ), milk yield (ZR, 22.9; HR, 13.2 kg·d -1 ) and milk fat concentration (ZR, 42.1; HR, 33.4 g·kg -1 ) which would not be commercially sustainable unless a considerable pre- mium was paid for this modified milk. It seems likely that the optimum dose of dietary rapeseed is lower than used in this study.

There is an urgent need to treat individuals with high blood pressure (BP) with effective dietary strategies. Previous studies suggest a small, but significant decrease in BP after lactotripeptides (LTP) ingestion, although the data are inconsistent. The study aim was to perform a comprehensive meta-analysis of data from all relevant randomised controlled trials (RCT). Medline, Cochrane library, EMBASE and Web of Science were searched until May 2014. Eligibility criteria were RCT that examined the effects of LTP on BP in adults, with systolic BP (SBP) and diastolic BP (DBP) as outcome measures. Thirty RCT met the inclusion criteria, which resulted in 33 sets of data. The pooled treatment effect for SBP was −2.95 mmHg (95% CI: −4.17, −1.73; p < 0.001), and for DBP was −1.51 mmHg (95% CI: −2.21, −0.80; p < 0.001). Sub-group analyses revealed that reduction of BP in Japanese studies was significantly greater, compared with European studies (p = 0.002 for SBP and p < 0.001 for DBP). The 24-h ambulatory BP (AMBP) response to LTP supplementation was statistically non-significant (p = 0.101 for SBP and p = 0.166 for DBP). Both publication bias and “small-study effect” were identified, which shifted the treatment effect towards less significant SBP and non-significant DBP reduction after LTP consumption. LTP may be effective in BP reduction, especially in Japanese individuals; however sub-group, meta-regression analyses and statistically significant publication biases suggest inconsistencies.

The consumption of supplements based on dairy or plant proteins may be associated with bioactive potential, including angiotensin-1-converting enzyme inhibitory (ACE-1i) activity, which is linked with blood pressure reduction in vivo. To gain insight into this proposed mechanism, the ACE-1i potential of protein-based supplements, including a selection of dairy (n = 10) and plant (n = 5) proteins were in vitro digested. The total digest was filtered and permeate and retentate were obtained. ACE-1i activity was measured as the ability of proteins (pre-digestion, ‘gastric’, permeate, and retentate) to decrease the hydrolysis of furanacroloyl-Phe-Glu-Glu (FAPGG) substrate for the ACE-1 enzyme. Permeate and retentate of dairy proteins exerted a significantly higher ACE-1i activity (mean of 10 proteins: 27.05 ± 0.2% and 20.7 ± 0.2%, respectively) compared with pre-digestion dairy proteins (16.7 ± 0.3%). Plant protein exhibited high ACE-1i in ‘gastric’ and retentate fractions (mean of five proteins: 54.9 ± 0.6% and 35.7 ± 0.6%, respectively). The comparison of the in vitro ACE-1i activity of dairy and plant proteins could provide valuable knowledge regarding their specific bioactivities, which could inform their use in the formulation of specific functional supplements that would require testing for blood pressure control in human randomly-controlled studies.

CVD are the leading cause of death worldwide. Hypertension, a major controllable risk factor of CVD, is intimately associated with vascular dysfunction, a defect which is also now recognised to be a major, modifiable risk factor for the development of CVD. The purpose of the present review was to critically evaluate the evidence for the effects of milk proteins and their associated peptides on blood pressure (BP) and vascular dysfunction. After a detailed literature search, the number of human trials evaluating the antihypertensive effects of casein-derived peptides (excluding isoleucine-proline-proline and valine-proline-proline) was found to be limited; the studies were preliminary with substantial methodological limitations. Likewise, the data from human trials that examined the effects of whey protein and peptides were also scarce and inconsistent. To date, only one study has conducted a comparative investigation on the relative effects of the two main intact milk proteins on BP and vascular function. While both milk proteins were shown to reduce BP, only whey protein improved measures of arterial stiffness. In contrast, a growing number of human trials have produced evidence to support beneficial effects of both milk proteins and peptides on vascular health. However, comparison of the relative outcomes from these trials is difficult owing to variation in the forms of assessment and measures of vascular function. In conclusion, there is an accumulating body of evidence to support positive effects of milk proteins in improving and/or maintaining cardiovascular health. However, the variable quality of the studies that produced this evidence, and the lack of robust, randomised controlled intervention trials, undermines the formulation of firm conclusions on the potential benefits of milk proteins and peptides on vascular health.

An increasing number of studies have reported a heritable component for the regulation of energy intake and eating behaviour, although the individual polymorphisms and their ‘effect size’ are not fully elucidated. The aim of the present study was to examine the relationship between specific SNP and appetite responses and energy intake in overweight men. In a randomised cross-over trial, forty overweight men (age 32 (sd 09) years; BMI 27 (sd 2) kg/m2) attended four sessions 1 week apart and received three isoenergetic and isovolumetric servings of dairy snacks or water (control) in random order. Appetite ratings were determined using visual analogue scales and energy intake at an ad libitum lunch was assessed 90 min after the dairy snacks. Individuals were genotyped for SNP in the fat mass and obesity-associated (FTO), leptin (LEP), leptin receptor (LEPR) genes and a variant near the melanocortin-4 receptor (MC4R) locus. The postprandial fullness rating over the full experiment following intake of the different snacks was 17·2 % (P= 0·026) lower in A carriers compared with TT homozygotes for rs9939609 (FTO, dominant) and 18·6 % (P= 0·020) lower in G carriers compared with AA homozygotes for rs7799039 (LEP, dominant). These observations indicate that FTO and LEP polymorphisms are related to the variation in the feeling of fullness and may play a role in the regulation of food intake. Further studies are required to confirm these initial observations and investigate the ‘penetrance’ of these genotypes in additional population subgroups.

Arterial stiffness is an independent predictor of cardiovascular disease events and mortality, and like blood pressure, may be influenced by dairy food intake. Few studies have investigated the effects of consumption of these foods on prospective measures of arterial stiffness. The present analysis aimed to investigate the prospective relationship between milk, cheese, cream, and butter consumption and aortic pulse wave velocity, augmentation index, systolic and diastolic blood pressure, as well as cross-sectional relationships between these foods and systolic and diastolic blood pressure and metabolic markers using data from the Caerphilly Prospective Study. Included in this cohort were 2512 men, aged 45 to 59 years, who were followed up at 5-year intervals for a mean of 22.8 years (number follow-up 787). Augmentation index was 1.8% lower in subjects in the highest quartiles of dairy product intake compared with the lowest ( P trend=0.021), whereas in the highest group of milk consumption systolic blood pressure was 10.4 mm Hg lower ( P trend=0.033) than in nonmilk consumers after a 22.8-year follow-up. Cross-sectional analyses indicated that across increasing quartiles of butter intake, insulin ( P trend=0.011), triacylglycerol ( P trend=0.023), total cholesterol ( P trend=0.002), and diastolic blood pressure ( P trend=0.027) were higher. Across increasing groups of milk intake and quartiles of dairy product intake, glucose ( P trend=0.032) and triglyceride concentrations ( P trend=0.031) were lower, respectively. The present results confirm that consumption of milk predicts prospective blood pressure, whereas dairy product consumption, excluding butter, is not detrimental to arterial stiffness and metabolic markers. Further research is needed to better understand the mechanisms that underpin these relationships.

Dietary regulation of appetite may contribute to the prevention and management of excess body weight. The present study examined the effect of consumption of individual dairy products as snacks on appetite and subsequent ad libitum lunch energy intake. In a randomised cross-over trial, forty overweight men (age 32 (sd 9) years; BMI 27 (sd 2) kg/m2) attended four sessions 1 week apart and received three isoenergetic (841 kJ) and isovolumetric (410 ml) servings of dairy snacks or water (control) 120 min after breakfast. Appetite profile was determined throughout the morning and ad libitum energy intake was assessed 90 min after the intake of snacks. Concentrations of amino acids, glucose, insulin, ghrelin and peptide tyrosine tyrosine were measured at baseline (0 min) and 80 min after the intake of snacks. Although the results showed that yogurt had the greatest suppressive effect on appetite, this could be confounded by the poor sensory ratings of yogurt. Hunger rating was 8, 10 and 24 % (P P se 226) kJ). Although there was no difference in the postprandial responses of hormones, alanine and isoleucine concentrations were higher after the intake of yogurt than cheese and milk (P

With the wide acceptance of the long-chain (LC) n-3 PUFA EPA and DHA as important nutrients playing a role in the amelioration of certain diseases, efforts to understand factors affecting intakes of these fatty acids along with potential strategies to increase them are vital. Widespread aversion to oil-rich fish, the richest natural source of EPA and DHA, highlights both the highly suboptimal current intakes in males and females across all age-groups and the critical need for an alternative supply of EPA and DHA. Poultry meat is a popular and versatile food eaten in large quantities relative to other meats and is open to increased LC n-3 PUFA content through manipulation of the chicken's diet to modify fatty acid deposition and therefore lipid composition of the edible tissues. It is therefore seen as a favourable prototype food for increasing human dietary supply of LC n-3 PUFA. Enrichment of chicken breast and leg tissue is well established using fish oil or fishmeal, but concerns about sustainability have led to recent consideration of algal biomass as an alternative source of LC n-3 PUFA. Further advances have also been made in the quality of the resulting meat, including achieving acceptable flavour and storage properties as well as understanding the impact of cooking on the retention of fatty acids. Based on these considerations it may be concluded that EPA- and DHA-enriched poultry meat has a very positive potential future in the food chain.

The beneficial effects of long-chain (C chainor=20) n-3 PUFA are well documented and, overall, increased intake reduces risk of CVD. Recent evidence also points to a role in reducing age-related decline in cognitive function. The two key fatty acids are EPA (20:5) and DHA (22:6), with current UK recommendation for adults being 450 mg EPA+DHA/d. Whilst some EPA and DHA can be synthesised in vivo from alpha-linolenic acid, recent data indicate this source to be very limited, suggesting that EPA and DHA should be classified as dietary essentials. In many parts of Europe the daily intake of EPA+DHA by adults and especially young adults (18-24 years) is100 mg/d, since many never eat oily fish. Poultry meat contributes small but worthwhile amounts of EPA+DHA. Studies to enrich the EPA+DHA content of animal-derived foods mainly use fish oil in the diet of the animal. Recent work has shown that such enrichment has the potential to provide to the UK adult diet a daily intake of EPA+DHA of about 230 mg, with poultry meat providing the largest amount (74 mg). There are, however, concerns that the continued and possibly increased use of fish oils in animals' diets is not sustainable and alternative approaches are being examined, including the genetic modification of certain plants to allow them to synthesise EPA and DHA from shorter-chain precursors.