Vitamin D deficiency in older adults has traditionally been of concern in relation to its role in maintaining bone mineral density. The effect of vitamin D on muscle strength and its influence on fall risk and prevention may have been underappreciated. A growing body of literature now focuses on the use of vitamin D for prevention of muscle atrophy, in particular type II muscle fibers that are associated with strength and function. Although by no means conclusive, research has now moved from initial cross-sectional analyses to interventional studies measuring changes in strength and muscle fiber size secondary to supplementation with vitamin D. This …