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Background Evidence is emerging that interdaily meal pattern variability potentially affects response such as thermic effect of food (TEF), macronutrient metabolism, and appetite. Objectives To investigate the effect of irregular meal pattern on TEF, glucose, insulin, lipid profile, and appetite regulation in women who are overweight or with obesity and confirmed insulin resistance. Design In a randomized crossover trial, 9 women [mean ± SD BMI (in kg/m2): 33.3 ± 3.1] with confirmed insulin resistance consumed a regular (14 d; 6 meals/d) and an irregular (14 d; 3–9 meals/d) meal pattern separated by a 14-d washout interval. Identical foods were provided during the interventions, and at the start and end of each meal pattern, participants attended the laboratory after an overnight fast. Energy expenditure, glucose, insulin, lipids, adiponectin, leptin, glucagon-like peptide 1 (GLP-1), peptide YY (PYY), and ghrelin were measured at baseline and for 3 h after consumption of a test drink, after which an ad libitum test meal was offered. Subjective appetite ratings were recorded before and after the test drink, after the ad libitum meal, and during the intervention. Continuous interstitial glucose monitoring was undertaken for 7 consecutive days during each intervention. Results TEF (over 3 h) was significantly lower postirregular intervention compared with postregular (97.7 ± 19.2 kJ*3 h in postregular visit and 76.7 ± 35.2 kJ*3 h in postirregular visit, paired t test, P = 0.048). Differences in HOMA-IR between the 2 interventions (3.3 ± 1.7 and 3.6 ± 1.6 in postregular and postirregular meal pattern, respectively) were not significant. Net incremental AUC for GLP-1 concentrations (over 3 h) for the postregular meal pattern were higher (864.9 ± 456.1 pmol/L*3 h) than the postirregular meal pattern (487.6 ± 271.7 pmol/L*3 h, paired t test, P = 0.005). Conclusions Following a 14-d period of an irregular meal pattern, TEF was significantly less than following a regular meal pattern, potentially compromising weight management if sustained long term. This study was registered at www.clinicaltrials.gov as NCT02582606. [ABSTRACT FROM AUTHOR]

Background Observed associations of high-protein diets with changes in insulin resistance are inconclusive. Objectives We aimed to assess associations of changes in both reported and estimated protein (PRep; PEst) and energy intake (EIRep; EIEst) with changes in HOMA-IR, glycated hemoglobin (HbA1c), and BMI (in kg/m2), in 1822 decreasing to 833 adults (week 156) with overweight and prediabetes, during the 3-y PREVIEW (PREVention of diabetes through lifestyle intervention and population studies In Europe and around the World) study on weight-loss maintenance. Eating behavior and measurement errors (MEs) of dietary intake were assessed. Thus, observational post hoc analyses were applied. Methods Associations of changes in EIEst, EIRep, PEst, and PRep with changes in HOMA-IR, HbA1c, and BMI were determined by linear mixed-model analysis in 2 arms [high-protein-low-glycemic-index (GI) diet and moderate-protein-moderate-GI diet] of the PREVIEW study. EIEst was derived from energy requirement: total energy expenditure = basal metabolic rate × physical activity level; PEst from urinary nitrogen, and urea. MEs were calculated as [(EIEst − EIRep)/EIEst] × 100% and [(PRep − PEst)/PEst] × 100%. Eating behavior was determined using the Three Factor Eating Questionnaire, examining cognitive dietary restraint, disinhibition, and hunger. Results Increases in PEst and PRep and decreases in EIEst and EIRep were associated with decreases in BMI, but not independently with decreases in HOMA-IR. Increases in PEst and PRep were associated with decreases in HbA1c. PRep and EIRep showed larger changes and stronger associations than PEst and EIEst. Mean ± SD MEs of EIRep and PRep were 38% ± 9% and 14% ± 4%, respectively; ME changes in EIRep and En% PRep were positively associated with changes in BMI and cognitive dietary restraint and inversely with disinhibition and hunger. Conclusions During weight-loss maintenance in adults with prediabetes, increase in protein intake and decrease in energy intake were not associated with decrease in HOMA-IR beyond associations with decrease in BMI. Increases in PEst and PRep were associated with decrease in HbA1c. This trial was registered at clinicaltrials.gov as NCT01777893. [ABSTRACT FROM AUTHOR]

Background: Circulating branched-chain amino acids (BCAAs) and aromatic amino acids (AAAs) have been shown to be associated with insulin resistance and diabetes risk. The common rs1440581 T allele in the protein phosphatase Mg2+/Mn2+ dependent 1K (PPM1K) gene has been related to elevated BCAA concentrations and risk of type 2 diabetes.Objective: In the present study, we tested whether dietary fat and carbohydrate intakes influenced the association between the rs1440581 PPM1K genetic variant and glucose-metabolism traits during weight loss.Design: The rs1440581 PPM1K genetic variant was genotyped in a total of 757 nondiabetic individuals who were randomly assigned to 1 of 2 energy-restricted diets that differed in macronutrient composition (low-fat diet: 20-25% fat, 15% protein, and 60-65% carbohydrate; high-fat diet: 40-45% fat, 15% protein, and 40-45% carbohydrate). The changes in fasting glucose, fasting insulin, insulin resistance (homeostasis model assessment of insulin resistance) and homeostasis model assessment of β cell function (HOMA-B) were measured after a mean ± SD weight loss of 6.8 ± 3.4 kg over 10 wk and analyzed according to the presence of the T allele of rs1440581.Results: The rs1440581 T allele was associated with a smaller improvement in glucose concentrations after the 10-wk dietary intervention (β ± SE: 0.05 ± 0.02 mg/dL; P = 0.03). In addition, significant gene-diet interactions were shown for the rs1440581 PPM1K genetic variant in relation to changes in insulin and HOMA-B (P-interaction = 0.006 and 0.002, respectively). In response to the high-fat diet, the T allele was associated with a higher reduction of insulin (β ± SE: -0.77 ± 0.40 µU/mL; P = 0.04) and HOMA-B (β ± SE: -13.2 ± 3.81; P = 0.003). An opposite effect was observed in the low-fat diet group, although in this group the T allele was marginally (P = 0.10) and not significantly (P = 0.24) associated with insulin and HOMA-B, respectively.Conclusion:PPM1K rs1440581 may affect changes in glucose metabolism during weight loss, and this effect is dependent on dietary fat and carbohydrate intakes. This trial was registered at controlled-trials.com as ISRCTN25867281. [ABSTRACT FROM AUTHOR]

Background: The effect of intensity and duration of physical activity (PA) on weight loss has been well described. However, the effect of the frequency of weekly PA on weight loss is still unknown. Objective: The purpose of this study was to evaluate the effect of the frequency of weekly PA sessions while maintaining the same total activity time on weight loss during a 24-wk weight loss program. Design: Overweight and obese women [n = 75; body mass index (BMI; in kg/m2): 27-37; age: 18-40 y] who had a normally sedentary lifestyle were randomly allocated to 1 of 2 intervention groups: a highfrequency physical activity (HF) or a low-frequency physical activity (LF) group. The HF group included 50 min/d PA, 6 d/wk (300 min/wk). The LF group included 100 min/d PA, 3 d/wk (300 min/wk). Both groups were advised to follow the same dietary weight loss program. Results: Both groups showed a significant decrease in anthropometric measurements and significant improvements in cardiometabolic disease risk characteristics over the 24 wk of the study. Compared with the HF group, the LF group had a greater decrease in weight (mean ± SD; LF: 9.58 ± 3.77 kg; HF: 7.78 ± 2.68 kg; P = 0.028), BMI (LF: 3.62 ± 1.56; HF: 2.97 ± 1.02; P = 0.029) and waist circumference (LF: 9.36 ± 4.02 cm; HF: 7.86 ± 2.41 cm; P = 0.031). However, there were no significant differences in carbohydrate metabolism characteristics or lipid profile after the 24 wk of intervention. Conclusion: Weekly PA undertaken over fewer sessions of longer duration during the week could be more effective for weight loss than when undertaken as more frequent shorter sessions in overweight and obese women on a weight loss program. This may be helpful for those who are neither willing nor able to schedule time for PA almost every day to achieve weight loss. This trial was registered at www.irct.ir as IRCT201402157754N4. [ABSTRACT FROM AUTHOR]

Background: The association between the time of nutrient intake and health has been described in a few studies. To our knowledge, no study has evaluated the relation between high energy intakes at lunch compared with at dinner on weight loss in overweight and obese subjects. Objective: We compared the effect of high energy intake at lunch with that at dinner on weight loss and cardiometabolic risk factors in women during a weight-loss program. Design: Overweight and obese women [n = 80; body mass index (BMI; in kg/m²): 27-35; age: 18-45 y] were asked to eat either a main meal at lunch (LM) or a main meal at dinner (DM) for 12 wk while in a weight-loss program. Results: A total of 80 participants were randomly assigned to one of 2 intervention groups. Sixty-nine subjects (86%) completed the trial (34 subjects in the DM group, and 35 subjects in the LM group). Baseline variables were not significantly different between groups. A significant reduction in anthropometric measurements and significant improvements in cardiometabolic risk characteristics were observed over 12 wk in both groups. Compared with the DM group, the LM group had greater mean ± SD reductions in weight (LM: -5.85 ± 1.96 kg; DM: -4.35 ± 1.98 kg; P = 0.003), BMI (LM: 2.27± 0.76; DM: 1.68 ± 0.76; P = 0.003), homeostasis model assessment of insulin resistance (LM: -0.66 ± 0.33; DM: -0.46 ± 0.24; P = 0.001), and fasting insulin (LM: -2.01 ± 1.10 mIU/mL; DM: -1.16 ± 0.72 mIU/mL; P < 0.001) after 12 wk. However, there were no significant differences for fasting plasma glucose and lipid profiles within both groups after 12 wk. Conclusions: The consumption of higher energy intake at lunch compared with at dinner may result in favorable changes in weight loss in overweight and obese women after a weight-loss program of 12 wk. The consumption may also offer clinical benefits to improve insulin resistance. [ABSTRACT FROM AUTHOR]

Background: Obesity is increasing in parallel with greater all-day food availability. The latter may promote meal irregularity, dysregulation of the energy balance, and poor metabolic health. Objective: We investigated the effect of meal irregularity on the thermic effect of food (TEF), lipid concentrations, carbohydrate metabolism, subjective appetite, and gut hormones in healthy women. Design: Eleven normal-weight women (18-40 y of age) were recruited in a randomized crossover trial with two 14-d isoenergetic diet periods (identical foods provided and free living) that were separated by a 14-d habitual diet washout period. In period 1, participants followed a regular meal pattern (6 meals/d) or an irregular meal pattern (3-9 meals/d), and in period 2, the alternative meal pattern was followed. Before and after each period, when participants were fasting and for 3 h after intake of a test drink, measurements were taken of energy expenditure, circulating glucose, lipids (fasting only), insulin, glucagon-like peptide 1 (GLP-1), peptide YY (PYY), and ghrelin. An ad libitum test meal was offered. Subjective appetite ratings were assessed while fasting, after the test drink, after the ad libitum meal, and during the intervention. Continuous interstitial glucose monitoring was undertaken for 3 consecutive days during each intervention, and the ambulatory activity pattern was recorded (ambulatory energy expenditure estimation). Results: Regularity was associated with a greater TEF (P, 0.05) and a lower incremental area under the curve (iAUC) for glucose after intake of the test drink (over 3 h) and, for some identical meals, during the 2 interventions (over 90 min) (day 7: after breakfast; day 9: after lunch and dinner). There was no difference between treatments for the test-drink gut hormone response. A time effect was noted for fasting GLP-1, fasting PYY, PYY responses, and hunger-rating responses to the test drink (P < 0.05). Lower hunger and higher fullness ratings were seen premeal and post-meal during the regular period while subjects were free living. Conclusion: Meal regularity appears to be associated with greater TEF and lower glucose responses, which may favor weight management and metabolic health. This trial was registered at clinical-trials.gov as NCT02052076. [ABSTRACT FROM AUTHOR]

Background: Despite evidence for the beneficial effects of probiotics and low-fat dairy products, to our knowledge, no study has compared the beneficial effect on weight loss of consuming a probiotic yogurt (PY) compared with a standard low-fat yogurt (LF) during a hypoenergetic program. Objective: We compared the effect of the PY with LF yogurt consumption on body weight and cardiometabolic risk factors in women during a weight-loss program. Design: Overweight and obese women [body mass index (in kg/m²): 27-40; age: 18-50 y) who usually consumed standard LFs were asked to consume either PY or LF every day with their main meals for 12 wk while following a weight-loss program. Results: A total of 89 participants were randomly assigned to one of the 2 intervention groups. Baseline variables were not significantly different between groups. A statistically significant reduction in anthropometric measurements and significant improvements in cardiometabolic risk characteristics were observed over the 12 wk in both groups. However, no significant differences in weight loss and anthropometric measurements were seen between groups after the intervention. Compared with the LF group, the PY group had a greater (mean ± SD) decrease in total cholesterol (PY = -0.36 ± 0.10 mmol/L, LF = --0.31 ± 0.10 mmol/L; P = 0.024), low-density lipoprotein cholesterol (PY = -0.35 ± 0.10 mmol/L, LF = -0.31 ± 0.11 mmol/L; P = 0.018), homeostasis model assessment of insulin resistance (PY = -0.55 ± 0.32, LF = -0.42 ± 0.20; P = 0.002), 2-h postprandial glucose (PY = -0.61 ± 0.24 mmol/L, LF = -0.44 ± 0.19 mmol/L; P < 0.001), and fasting insulin concentration (PY = -1.76 ± 1.01 mU/mL, LF = -1.32 ± 0.62 mU/mL; P = 0.002), as secondary endpoints after the study. No significant differences were found for fasting plasma glucose, high-density lipoprotein cholesterol, or triglycerides within both groups after the 12 wk. Conclusion: Consumption of PY compared with LF with main meals showed no significant effects on weight loss. However, it may have positive effects on lipid profiles and insulin sensitivity during a weight-loss program. This trial was registered at http:// www.irct.ir/ as IRCT201402177754N8. [ABSTRACT FROM AUTHOR]

Background: Obese people believe that drinking diet beverages (DBs) may be a simple strategy to achieve weight loss. However, nutritionists advise drinking water when attempting to lose weight. It is unclear how important drinking water instead of DBs is during a weight-loss program. Objective: In this study, we compared the effect on weight loss of either replacing DBs with water or continuing to consume DBs in adults during a 24-wk weight-loss program. Design: Overweight and obese women [n = 89; body mass index (BMI; in kg/m²): 27-40; age: 18-50 y] who usually consumed DBs in their diet were asked to either substitute water for DBs (water group) or continue drinking DBs 5 times/wk after their lunch for 24 wk (DB group) while on a weight-loss program. Results: Sixty-two participants (71%) completed the trial (32 in the DB group, 30 in the water group). Baseline variables were not statistically significantly different between groups. A statistically significant reduction in anthropometric measurements and statistically significant improvements in cardiometabolic risk characteristics were observed over 24 wk in both groups. Compared with the DB group, the water group had a greater decrease in weight (mean ± SD: water: 28.8 ± 1.9 kg; DBs: 27.6 ± 2.1 kg; P = 0.015, time 3 group), fasting insulin (mean ± SD: water: 22.84 ± 0.77 mU/L; DBs: 21.78 ± 1.25 mU/L, P < 0.001), homeostasis model assessment of insulin resistance (mean ± SD: water: 20.097 ± 0.049; DBs: 20.057 ± 0.042, P < 0.001), and 2-h postprandial glucose (mean ± SD: water: 21.02 ± 0.25 mmol/L; DBs: 20.72 ± 0.27 mmol/L; P < 0.001) over the 24 wk. However, there was no significant time 3 group interaction for waist circumference, fasting plasma glucose, and lipid profiles within both groups over 24 wk. Conclusions: Replacement of DBs with water after the main meal may lead to greater weight reduction during a weight-loss program. It may also offer clinical benefits to improve insulin resistance. This trial was registered at www.irct.ir/ as IRCT201402177754N5. [ABSTRACT FROM AUTHOR]

Background: The manipulation of the composition of foods consumed as between-meal snacks may aid daily energy restriction. Objectives: We compared the effects of the consumption of 2 energy-matched snack bars on appetite, energy intake (EI), and metabolic and endocrine responses. In addition, we investigated whether the acute effects of the consumption of snacks were maintained under free-living conditions and whether the habitual daily consumption of the snack over 14 d influenced these effects. Design: Ten lean men [mean ± SD age: 30.7 ± 9.7 y; body mass index (in kg/m²): 23.2 ± 2.8] consumed a whey protein and polydextrose (PPX) snack bar or an isoenergetic control snack bar as a midmorning, between-meal snack for 14 consecutive days in a double-blind, randomized, crossover design. The two 14-d intervention phases were separated by a 14-d washout period. On the first (day 1) and last (day 15) days of each intervention phase, appetite, food intake, and blood metabolite and endocrine responses were assessed under laboratory conditions. Free-living EI was recorded on days 4, 8, and 12 of interventions. Results: Total daily EI was significantly lower when the PPX snack was consumed during experimental days (10,149 ± 831 compared with 11,931 ± 896 kJ; P < 0.01), and daily EI remained lower when the PPX snack was consumed during the free-living part of the intervention (7904 ± 610 compared with 9041 ± 928 kJ; P < 0.05). The PPX snack was associated with lower glucose and ghrelin and higher glucagon-like peptide 1 and peptide tyrosine-tyrosine responses. Conclusion: The manipulation of the composition of foods consumed as snacks is an effective way to limit subsequent EI. This trial was registered at clinicaltrials.gov as NCT01927926. [ABSTRACT FROM AUTHOR]

The article discusses issues related to metabolic requirements for dietary carbohydrates. Topics discussed include physiological factors affecting metabolic requirements for dietary carbohydrate, end product of carbohydrate digestion and association between dietary carbohydrates and sodium retention in human body. It also discusses interrelationship between various dietary carbohydrate and vitamins and their role in the well-being of human population.

Cell-free extracts were prepared from mixed fecal anaerobic bacteria grown from stools of 14 vegetarian Seventh-Day Adventists, 16 omnivorous control subjects, and eight patients recently diagnosed with cancer of the large bowel. Preparations were assayed for NAD- and NADP-dependent 3α-, 7α- and 12α-hydroxysteroid dehydrogenases with bile salts and androsterone as substrates (eight substrate-cofactor combinations were tested). A significant intergroup difference was observed in the amounts of NAD- and NADP-dependent 7α-hydroxysteroid dehydrogenase produced: bowel cancer patients exceeded controls, and controls exceeded Seventh-Day Adventists. Other enzyme activity comparisons were not significant. The pH values of the stools were significantly higher in cancer patients compared to Seventh-Day Adventists; values were 7.03 ± 0.60 and 6.46 ± 0.58 respectively. The pH value for controls was 6.66 ± 0.62. A plot of pH value versus NADP-dependent 7α-hydroxysteroid dehydrogenase tended to separate the cancer patients from the other groups. Comparative data suggest that much of the 3α-hydroxysteroid dehydrogenase active against bile salt is also active against androsterone. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Snacks Containing Whey Protein and Polydextrose Induce a Sustained Reduction in Daily Energy Intake Over 2 Wk Under Free-Living Conditions," by Nerys M. Astbury and colleagues, along with the authors' response to the letter.

The article discusses research being done on the relationship between food and brain activation. It references the study "Effects of Dietary Glycemic Index on Brain Regions Related to Reward and Craving in Men," by B. S. Lennerz et al published in the 2013 issue of the "American Journal of Clinical Nutrition." The researchers used functional magnetic resonance imaging (fMRI) in assessing brain activation which may be caused by glycemic index (GI) level from food intake.

The article summarizes the views of the members of the panel on Simple and Complex Carbohydrates on factors to be considered for suggesting dietary recommendations for carbohydrate. The panel felt that the dietary recommendations were incomplete if the physiological variant of exercise was not considered. It explains the relationship between dental caries and simple carbohydrate intake.

Background: Owing to its role in glucose homeostasis, liver glycogen concentration ([LGly]) can be a marker of altered metabolism seen in disorders that impact the health of children. However, there is a paucity of normative data for this measure in children to allow comparison with patients, and time-course assessment of [LGly] in response to feeding has not been reported. In addition, carbon-13 magnetic resonance spectroscopy ( 13 C-MRS) is used extensively in research to assess liver metabolites in adult health and disease noninvasively, but similar measurements in children are lacking., Objectives: The main objectives were to quantify the depletion of [LGly] after overnight fasting and the subsequent response to feeding., Methods: In a randomly assigned, open-label, incomplete block design study, healthy, normal-weight children (8-12 y) attended 2 evening visits, each separated by ≥5 d and directly followed by a morning visit. An individually tailored, standardized meal was consumed 3-h prior to evening assessments. Participants then remained fasted until the morning visit. [LGly] was assessed once in the fed (20:00) and fasted state (08:00) using 13 C-MRS. After the 8:00 assessment, 200 ml of a mixed-macronutrient drink containing 15.5 g (402 kJ) or 31 g carbohydrates (804 kJ), or water only, was consumed, with 13 C-MRS measurements then performed hourly for 4 h. Each child was randomly assigned to 2 of 3 drink options across the 2 mornings. Data are expressed as mean (SD)., Results: Twenty-four children including females and males (13F:11M) completed the study [9.9 (1.1) y, BMI percentile 45.7 (25.9)]. [LGly] decreased from 377.9 (141.3) to 277.3 (107.4) mmol/L overnight; depletion rate 0.14 (0.15) mmol/L min. Incremental responses of [LGly] to test drinks differed (P < 0.001), with incremental net area under the curve of [LGly] over 4 h being higher for 15.5 g [-67.1 (205.8) mmol/L·240 min; P < 0.01] and 31 g carbohydrates [101.6 (180.9) mmol/L·240 min; P < 0.005] compared with water [-253.1 (231.2) mmol/L·240 min]., Conclusions: After overnight fasting, [LGly] decreased by 22.9 (25.1)%, and [LGly] incremental net area under the curve over 4 h was higher after subsequent consumption of 15.5 g and 31 g carbohydrates, compared to water. Am J Clin Nutr 20XX;xx:xx-xx., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)