Multivitamin supplementation of Wistar rats during pregnancy accelerates the development of obesity in offspring fed an obesogenic diet.

OBJECTIVE: The effect of gestational multivitamin supplementation on the development of obesity in rat offspring fed an obesogenic diet was investigated. DESIGN: Pregnant Wistar rats (n=10 per group) were fed the AIN-93G diet with the recommended vitamin (RV) content or a 10-fold increase (high vitamin, HV). At weaning, 10 males and 10 females, from separate dams, and from each gestational diet group were weaned to the liquid obesogenic diet for 48 weeks post-weaning. MEASUREMENTS: Body weight (BW) was measured weekly, and food intake over 24 h was measured once every 3 weeks for 24 weeks. Every 4 weeks, after an overnight fast, food intake over 1 h was measured 30 min after a gavage of water or glucose. An oral glucose tolerance test (OGTT) was carried out every 3-5 weeks. Post-weaning fasting glucose, insulin, ghrelin, glucagon-like peptide 1 (GLP-1), and systolic blood pressure (SBP) were measured. RESULTS: No difference in BW at birth or litter size was observed. Males and females from HV dams gained 17% (P<0.05) and 37% (P<0.001) more BW at 48 weeks post-weaning, and consumed 18% (P=0.07) and 20% (P<0.05) more food. One-hour food intake after water and glucose preloads was 27% (P<0.01) and 34% (P<0.05) higher in males from HV dams. Fasting ghrelin and GLP-1 were 27 and 32% higher in males from HV dams at weaning (P<0.05). Blood glucose response to the OGTT was greater in both males and females from HV dams at 13 weeks post-weaning (P<0.05), and the insulin resistance index was 76 and 43% higher in females from HV dams at 14 and 28 weeks post-weaning (P<0.05). SBP was 23 and 16% higher at 44 weeks post-weaning in male and females (P<0.01). CONCLUSION: High multivitamin intake during pregnancy increases the phenotypic expression of obesity and components of the metabolic syndrome in both female and male rats fed an obesogenic diet.

Effects of Milk Proteins Supplementation in Older Adults Undergoing Resistance Training: A Meta-Analysis of Randomized Control Trials.

BACKGROUND: Older adults experience age-related physiological changes that affect body weight and body composition. In general, nutrition and exercise have been identified as potent stimulators of protein synthesis in skeletal muscle. Milk proteins are excellent sources of all the essential amino acids and may represent an ideal protein source to promote muscle anabolism in older adults undergoing resistance training. However, several randomized control trials (RCTs) have yielded mixed results on the effects of milk proteins supplementation in combination with resistance training on body weight and composition. METHODS: PubMed, Web of Science and Cochrane databases were searched for literature that evaluated the effects of milk proteins supplementation on body weight and composition among older adults (age ≥ 60 years) undergoing resistance training up to September 2016. A random-effects model was used to calculate the pooled estimates and 95% confidence intervals (CIs) of effect sizes. RESULTS: The final analysis included 10 RCTs involving 574 participants (mean age range from 60 to 80.8 years). Overall, the combination of milk proteins supplementation and resistance training did not have significant effect on fat mass (0.30, 95% CI -0.25, 0.86 kg) or body weight (1.02, 95% CI: -0.01, 2.04 kg). However, a positive effect of milk proteins supplementation paired with resistance training on fat-free mass was observed (0.74, 95% CI 0.30, 1.17 kg). Greater fat-free mass gains were observed in studies that included more than 55 participants (0.73, 95% CI 0.30, 1.16 kg), and in studies that enrolled participants with aging-related medical conditions (1.60, 95% CI 0.92, 2.28 kg). There was no statistical evidence of publication bias among the studies. CONCLUSION: Our findings provide evidence that supplementation of milk protein, in combination with resistance training, is effective to elicit fat-free mass gain in older adults.

Effect of whey protein on blood lipid profiles: a meta-analysis of randomized controlled trials.

Previous studies have suggested that whey supplementation may have beneficial effects on lipid profiles, although results were inconsistent. A literature search was performed in March 2015 for randomized controlled trials observing the effects of whey protein and its derivatives on circulating levels of triacylglycerol (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C). A meta-analysis was subsequently conducted. The meta-analysis results of 13 trials showed that whey supplementation significantly reduced the circulating TG level by 0.11 mmol/l (95% CI: -0.21, 0 mmol/l), whereas the whey protein had no effects on circulating TC (-0.11 mmol/l, 95% CI: -0.27, 0.05 mmol/l), LDL-C (-0.08 mmol/l, 95% CI: -0.23, 0.07 mmol/l) and HDL-C (0.01 mmol/l, 95% CI: -0.04, 0.05 mmol/l). Subgroup analysis showed that significant TG reduction disappeared in participants with low body mass index, low supplemental whey dose or under exercise training/energy restriction during the trial. No evidence of heterogeneity across studies and publication bias was observed. In conclusion, our findings demonstrated that the effects of whey protein supplementation were modest, with an overall lowering effect on TG but no effect on TC, LDL-C and HDL-C.

The effect of high multivitamin diet during pregnancy on food intake and glucose metabolism in Wistar rat offspring fed low-vitamin diets post weaning.

Rat offspring born to dams fed a high multivitamin diet (HV) are shown to have increased risks of obesity and metabolic syndrome. We hypothesized that a low-vitamin postweaning diet would enhance these characteristics in offspring born to HV dams. During pregnancy, Wistar rats were fed the AIN-93G diet with or without a 10-fold increase in vitamin content. In Experiment 1, at weaning, males were fed the recommended diet (RV) or a diet with 1/3 the vitamin content (1/3 RV) for 12 weeks. In Experiment 2, males and females were fed the RV diet or 1/6 RV diet for 35 weeks. Body weight was measured on a weekly basis, food intake on a daily basis, and for 1 h after an overnight fast following glucose gavage at 6, 12 and 24 weeks. Blood glucose and insulin responses to an oral glucose load were measured at 30 weeks. Males from HV dams, compared with those from RV dams, gained more weight in Experiment 1 (+7%, P < 0.05) and Experiment 2 (+11%, P < 0.0001), along with higher glucose response (+33%, P < 0.05). The 1/6 RV pup diet led to lower weight gain in males (-16%, P < 0.0001) and females (-13%, P < 0.0005), and lower food intake in males (-9%, P < 0.01) independent of the gestational diet. Females on the 1/6 RV diet and from HV dams had higher 1 h food intake (+36%, P < 0.05) and lower insulin response (-25%, P < 0.05) compared with those from RV dams. Exposure of the offspring to low-vitamin diets did not amplify the expression of the metabolic syndrome observed in those born to dams fed an HV diet.