November 18, 2010
Researchers Learn That Genetics Determine Winter Vitamin D Status
Other factors predominate in summer
Vitamin D is somewhat of an unusual "vitamin," because it can be made in the body from sunlight and most foods do not contain vitamin D unless added by fortification. Synthesis of vitamin D in the body requires exposure to ultraviolet light and can be influenced by genetics, skin color, and sun exposure. Reports of greater than expected vitamin D insufficiency coupled with emerging evidence that higher circulating concentrations of this nutrient may protect against cardiovascular disease have prompted a renewed interest in teasing out how environment, genetics, and behavior work independently and coordinately to influence vitamin D status. To help clarify this, researchers at Emory University studied vitamin D status in twins living in different North American locations. You can read more about this study in the December 2010 issue of the American Journal of Clinical Nutrition.
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