Chronic vitamin D insufficiency impairs physical performance in C57BL/6J mice.

Vitamin D insufficiency (serum 25-OH vitamin D < 30 ng/ml) affects 70-80% of the general population, yet the long-term impacts on physical performance and the progression of sarcopenia are poorly understood. We therefore followed 6-month-old male C57BL/6J mice (=6) consuming either sufficient (STD, 1000 IU) or insufficient (LOW, 125 IU) vitamin D3/kg chow for 12 months (equivalent to 20-30 human years). LOW supplemented mice exhibited a rapid decline of serum 25-OH vitamin D levels by two weeks that remained between 11-15 ng/mL for all time points thereafter.

Studies on prevention of obesity, metabolic syndrome, diabetes, cardiovascular diseases and cancer by tea.

Tea, a popular beverage made from leaves of the plant Camellia sinensis, has been studied extensively in recent decades for its beneficial health effects in the prevention of obesity, metabolic syndrome, diabetes, cancer, and other diseases. Whereas these beneficial effects have been convincingly demonstrated in most laboratory studies, results from human studies have not been consistent. Some studies demonstrated that weight reduction, alleviation of metabolic syndrome and risk reduction in diabetes were only observed in individuals who consume 3-4 cups of tea (600-900 mg tea catechins) or more daily.

A mouse model of vitamin D insufficiency: is there a relationship between 25(OH) vitamin D levels and obesity?

Background: Vitamin D insufficiency (serum 25-OH vitamin D > 10 ng/ml and < 30 ng/ml) is prevalent in the obese (body mass index (BMI) > 30 kg/m), yet relationships between the two are poorly understood. Objectives of this study include identification of the impact of obesity on reducing serum 25-OH vitamin D concentration, particularly in response to altered vitamin D supplementation, and to elucidate the longitudinal impact of serum 25-OH vitamin D on body mass index.

Methods: Twenty four-week-old lean and obese male C57BL/6 J mice were fed low, standard, or high levels of cholecalciferol supplementation and followed for 24 weeks.