Association between circulating endogenous androgens and insulin sensitivity changes with exercise training in midlife women.

Objective: Aging induces a shift in circulating hormones in women, accompanied by weight gain during the late reproductive, menopausal transition, and postmenopausal years. Exercise has been shown to counter weight gain; however, it might increase circulating androgens. A 6-month aerobic and resistance training exercise regimen was implemented to examine interrelationships between circulating sex hormones, body composition, aerobic capacity, insulin sensitivity, and insulin resistance.

Improved metabolic health alters host metabolism in parallel with changes in systemic xeno-metabolites of gut origin.

Novel plasma metabolite patterns reflective of improved metabolic health (insulin sensitivity, fitness, reduced body weight) were identified before and after a 14-17 wk weight loss and exercise intervention in sedentary, obese insulin-resistant women. To control for potential confounding effects of diet- or microbiome-derived molecules on the systemic metabolome, sampling was during a tightly-controlled feeding test week paradigm. Pairwise and multivariate analysis revealed intervention- and insulin-sensitivity associated: (1) Changes in plasma xeno-metabolites ("non-self" metabolites of dietary or gut microbial origin) following an oral glucose tolerance test (e.

High-selenium yeast supplementation in free-living North American men: no effect on thyroid hormone metabolism or body composition.

In a prior study, we observed decreased serum 3,3',5-triiodothyronine (T(3)), increased serum thyrotropin and increased body weight in five men fed 297 microg/d of selenium (Se) in foods naturally high in Se while confined in a metabolic research unit. In an attempt to replicate and confirm those observations, we conducted a randomized study of high-Se yeast supplements (300 microg/d) or placebo yeast administered to 42 healthy free-living men for 48 weeks. Serum thyroxine, T(3) and thyrotropin did not change in supplemented or control subjects.