Obesity affects over one-third of Americans and increases the risk of cardiovascular disease and type II diabetes. Interventional trials have consistently demonstrated that consumption of plant-based diets reduces body fat in overweight and obese subjects, even when controlling for energy intake. Nonetheless, the mechanisms underlying this effect have not been well-defined. This review discusses six major dietary mechanisms that may lead to reduced body fat. These include (1) reduced caloric density, (2) improved gut microbiota symbiosis, (3) increased insulin sensitivity, (4) reduced trimethylamine-N-oxide (TMAO), (5) activation of peroxisome proliferator-activated receptors (PPARs), and (6) over-expression of mitochondrial uncoupling proteins. Collectively, these factors improve satiety and increase energy expenditure leading to reduced body weight.

Oxidative stress and inflammation are central to the development of a number of chronic diseases including cardiovascular disease and previous research suggests that blueberry consumption may attenuate these processes. The present study investigated the effects of blueberries on blood biomarkers of oxidative stress, inflammation, and antioxidant defense in postmenopausal women with pre- and stage 1-hypertension. In a randomized, parallel-arm, double-blind, placebo-controlled clinical trial, 40 pre- and stage 1-hypertensive postmenopausal women aged 45 to 65 years were randomly assigned to receive 22 g freeze-dried highbush blueberry powder per day (Blueberry) or 22 g placebo powder per day (Control) for 8 weeks. A blood biomarker of oxidative DNA damage, 8-hydroxy-2′-deoxyguanosine (8-OHdG), as well as blood biomarkers of oxidative stress, inflammation, and antioxidant defense were assessed at baseline, 4 and 8 weeks. 8-OHdG levels were significantly (P = 0.008) lower in Blueberry compared to Control at 4 weeks with a significant time-by-treatment interaction (P = 0.04). Levels were not different between groups at 8 weeks. Other biomarkers measured were not affected by blueberry consumption. Daily consumption of blueberries for 4 weeks, but not 8 weeks, attenuated a biomarker of oxidative DNA damage in pre- and stage 1-hypertensive postmenopausal women. Future clinical studies should directly evaluate the effects of blueberry consumption on oxidative stress, inflammation, and antioxidant defense at the cellular level and in the vasculature in this population.

Menopause leads to an increased risk for osteoporosis in women. Although drug therapies exist, increasing numbers of people prefer alternative therapies such as dietary supplements, for example, calcium, vitamin D, and collagen hydrolysates for the prevention and treatment of osteoporosis. We have previously shown that a 3-month intervention using a calcium-collagen chelate (CC) dietary supplement was efficacious in improving bone mineral density (BMD) and blood biomarkers of bone turnover in osteopenic postmenopausal women. This study reports the long-term efficacy of CC in reducing bone loss in postmenopausal women with osteopenia. Thirty-nine women were randomly assigned to one of two groups: 5 g of CC containing 500 mg of elemental calcium and 200 IU vitamin D (1,25-dihydroxyvitamin D ₃ ) or control (500 mg of calcium and 200 IU vitamin D) daily for 12 months. Total body, lumbar, and hip BMD were evaluated at baseline, 6 and 12 months using dual-energy X-ray absorptiometry. Blood was collected at baseline, 6 and 12 months to assess levels of blood biomarkers of bone turnover. Intent-to-treat (ITT) analysis was performed using repeated measures analysis of variance pairwise comparisons and multivariate analysis to assess time and group interactions. The loss of whole body BMD in women taking CC was substantially lower than that of the control group at 12 months in those who completed the study and the ITT analysis, respectively (CC: −1.33% and −0.33% vs. control: −3.75% and −2.17%; P =.026, P =.035). The CC group had significantly reduced levels of sclerostin and tartrate-resistant acid phosphatase isoform 5b (TRAP5b) ( P <.05), and higher bone-specific alkaline phosphatase/TRAP5b ratio ( P <.05) than control at 6 months. These results support the use of CC in reducing bone loss in osteopenic postmenopausal women.