Vitamin D, outdoor happiness, and the meaning of deficiency.

摘要

Lee et al. (1) informatively review the emerging evidence for vitamin D as a lifestyle risk factor for cardiovascular disease. Two overlooked points should be highlighted. First, as the investigators note, the great majority of vitamin D is derived from sun exposure, rather than dietary consumption. Thus, effect estimates in studies of vitamin D levels and cardiovascular risk may be confounded, at least in part, by challenging-to-measure differences in lifestyles, behaviors, dispositions, and opportunities that lead individuals to enjoy and spend time in the sun, such as physical and social activities. Whereas vitamin D itself may still provide benefit, being outside and enjoying these activities are likely to provide additional health benefits that erroneously may be attributed as effects of vitamin D.