Dietary interventions for cardiometabolic health

Alcantara and Miranda-Tapia et al. discuss the central mechanisms that dictate eating behaviour, by dissecting the neural circuits involved in food procurement, food consumption, and meal termination.

In metabolic studies using rodents, body weight and food intake measurements seem easy to obtain, but several potential pitfalls can lead to erroneous data generation and interpretation. This Comment raises awareness of key conceptual and technical aspects that can increase the quality and reproducibility of this type of data.

Beals, Kayser et al. demonstrate that exercise, in conjunction with diet-induced weight loss, causes greater improvement in whole-body insulin sensitivity than matched diet-induced weight loss alone in people with obesity and prediabetes.

Time-restricted feeding in the resting period is a potent dietary regimen to enhance running endurance in mice, by synchronizing rhythms of perilipin-5 in muscle tissues through involvement of the circadian clock.

Results from a randomized clinical trial show that adding exercise to diet-induced weight loss can improve beta-cell function, measured as late-phase disposition index, in people with newly diagnosed type 2 diabetes.

The authors provide evidence in mice and humans showing that parenteral nutrition impairs glucose and insulin homeostasis by altering the gut microbiota and its metabolites.

Zhong et al. show that increased lipid intestinal absorption can contribute to fat mass increase after dieting and this is mediated by Lactobacillus-secreted metabolites. Notably, Lactobacillus growth can be counteracted by refeeding a high-protein diet, thus preventing weight regain.

Ceasrine et al. show that a maternal high-fat diet leads to impaired serotonin bioavailability in the male fetal brain by disrupting the placenta–brain axis, which can cause long-lasting behavioural changes in the offspring.

Extended exposure to breastfeeding in rodent pups protects them from diet-induced obesity in adulthood by increasing thermogenesis and energy expenditure. This is mediated by liver-derived FGF21 signalling to the lateral hypothalamic area.

Interplay of western diet and gut microbiota has been reported to be involved in the development of nonalcoholic steatohepatitis (NASH). Here the authors report that Blautia producta and 2-oleoylglycerol are bacterial and metabolic mediators that promote liver inflammation and hepatic fibrosis in male mice.

Time-restricted eating, both early (eTRF) and mid-day (mTRF), have been shown to have metabolic benefits. Here the authors report a randomized controlled trial to compare the effects of eTRF and mTRF in healthy volunteers without obesity, and find that eTRF is more effective in improving the primary outcome insulin sensitivity.

Weight regain after weight loss is a challenge in obesity treatment and may involve altered eating and sedentary behaviour after weight loss. Here the authors report an exploratory analysis of eating- and physical activity-related outcomes from a randomized controlled trial for weight loss maintenance with exercise and liraglutide single or combination treatment.