Vitamin D has received widespread attention for its potential role in preventing cardiovascular disease (CVD) and type 2 diabetes mellitus. Several epidemiological studies have suggested that individuals with low blood levels of vitamin D have increased risks of heart disease, stroke, hypertension, and diabetes. Yet, the revised 2011 Institute of Medicine report for intake of calcium and vitamin D, which was guided by skeletal health alone, concluded that the evidence that vitamin D prevents CVD, diabetes, or other cardiometabolic outcomes was inconsistent and inconclusive and did not meet criteria for establishing a cause and effect relationship [1•, 2]. This finding was consistent with an earlier systematic review conducted by the Agency for Healthcare Research and Quality (AHRQ) in 2009 [3•]. Ongoing clinical trials seek to address the effects of vitamin D supplementation on CVD and other nonskeletal outcomes.