Low vitamin D may weaken muscles

Insufficient blood levels of vitamin D may be associated with the accumulation of fat in muscle tissue, leading to lower muscle strength, says a new study.

In the study, blood levels of 25- hydroxyvitamin D (25(OH)D), the non-active 'storage' form of the vitamin, as well as levels of fat, muscle mass, and percent muscle fat were measured in 90 young women aged between 16 and 22 (1). The results showed that almost 60 percent were vitamin D insufficient, equivalent to blood levels lower than 29 nanograms per milliliter, of which 24 percent were classed as vitamin D deficient (levels below 20 ng/ml). Additionally, muscle fat levels were higher in these women, compared with women with normal vitamin D levels.

The findings are said to be the first to show a clear link between vitamin D levels and the accumulation of fat in muscle tissue, and add to an ever growing body of science supporting the benefits of maintaining healthy vitamin D levels.

It is not yet know whether vitamin D supplementation would actually result in less accumulation of fat in the muscles or increase muscle strength, the researchers commented. More research is needed before interventions can be recommended.

1. Gilsanz V. et al. Vitamin D Status and Its Relation to Muscle Mass and Muscle Fat in Young Women. Journal of Clinical Endocrinology and Metabolism. 2010.