Wheat germ supplementation has modest effects on gut health markers but improves glucose homeostasis markers in adults classified as overweight: A randomized controlled pilot study.

Wheat germ (WG), a by-product of flour milling, is rich in bioactive substances that may help improve health complications associated with increased adiposity. This study investigated the effects of WG on gut health, metabolic, and inflammatory markers in adults classified as overweight. We hypothesized that WG, because of its many bioactive components, would improve gut health and metabolic, and inflammatory markers in overweight adults. Forty adults (18-45 years old) and with a body mass index between 25 and 30 kg/m2 participated in this single-blinded randomized controlled pilot study. Participants consumed the study supplements containing 30 g of either cornmeal (control, CL) or WG daily for 4 weeks. Primary outcome variables were gut health markers including gut microbiota, gut integrity markers, and fecal short-chain fatty acids, whereas secondary outcome variables included metabolic and inflammatory parameters assessed at baseline and at the end of supplementation. Thirty-nine participants (n = 19 and 20 for CL and WG group, respectively) completed the study. The genus Faecalibacterium was significantly higher in the WG group compared to CL post-supplementation but no significant changes in other gut health markers, short-chain fatty acids, inflammatory markers, and lipid profiles were observed. Compared with baseline, WG improved markers of glucose homeostasis including insulin (P = .02), homeostatic model assessment of insulin resistance (P = .03), glycated hemoglobin (P = .07), and the pro-inflammatory adipokine, resistin (P = .04). However, these parameters after intervention were not different with control. Our findings suggest that WG supplementation have modest effects on gut health but may provide an economical option for individuals to improve glycemic control.

Montmorencytart cherry supplementation improved markers of glucose homeostasis but has modest effects on indicators of gut health in mice fed a Western diet.

The gut microbiota plays an important role in the pathophysiology of obesity and type 2 diabetes. Emerging evidence suggests that anthocyanin-rich foods such as US Montmorency tart cherry (TC) can promote health by influencing the gut microbiota and maintaining gut integrity. This study investigated the effects of TC supplementation on the gut microbiota, markers of gut health, and metabolic parameters in mice fed a western diet (WD). Seventy-two C57BL/6 male mice were assigned to dietary treatments in a 2 × 3 factorial design with diet (control, WD) and TC (0, 5, 10% wt/wt) as factors. After 12 weeks of dietary treatment, tissues were collected to evaluate metabolic parameters and markers of gut health including cecal content microbiota and fecal short chain fatty acids (SCFAs). TC supplementation significantly increased the bacterial phylum, Actinobacteria, cecal weight, and fecal SCFAs and reduced the Proteobacteria and Deferribacteres phyla. However, gut histological parameters and expression of genes related to gut integrity were unaffected by TC. Body weight, serum cholesterol, triglyceride, leptin, plasminogen activator inhibitor-1 and resistin were increased with WD and TC had no effect on these parameters. Fasting blood glucose and the surrogate marker of insulin resistance, homeostatic model assessment of insulin resistance (HOMA-IR), was significantly increased by WD which was improved by TC particularly the 5% dose. In conclusion, TC supplementation, particularly the 5% dose, improved markers of glucose homeostasis but has modest effects on gut microbial population and SCFAs production. The mechanism by which TC improved markers of glucose homeostasis needs to be further investigated.