Vitamin D supplementation doesn't change lean mass, BMD

(HealthDay)—For postmenopausal women with vitamin D insufficiency completing a structured weight-loss program, vitamin D₃ supplementation is not associated with changes in lean mass or bone mineral density (BMD), according to a study published online April 5 in the Journal of the American Geriatrics Society.

Caitlin Mason, Ph.D., from the Fred Hutchinson Cancer Research Center in Seattle, and colleagues compared the effects of 12 months of vitamin D₃ supplementation with placebo in 218 postmenopausal women aged 50 to 75 years with a body mass index of 25 kg/m² or greater with vitamin D insufficiency. Participants were randomized to oral vitamin D₃ or placebo in combination with a lifestyle-based weight loss intervention.

The researchers found that at 12 months there were significantly different changes in 25-hydroxyvitamin D between the vitamin D and placebo groups (13.6 ng/mL versus −1.3 ng/ml; P < 0.001), but no significant differences in the change in lean mass (P = 0.53), BMD of the spine (P = 0.82), or BMD of the right femoral neck (P = 0.49). There was a decrease in leg strength in the vitamin D group but not in the placebo group (P = 0.03). For women randomized to the vitamin D group, results were not altered for those achieving repletion.

"Vitamin D₃ supplementation during weight loss decreased leg strength but did not alter changes in lean mass or BMD in postmenopausal women with vitamin D insufficiency," the authors write.