Vitamin D in Foods

Abstract Accurate data for vitamin D in foods are essential to support epidemiological and clinical studies seeking to identify associations between total vitamin D “exposure” and health outcomes that require quantification of dietary intake and also to inform health professionals about wise food choices for clients. Challenges in developing reliable vitamin D food composition data encompass the existence of multiple forms of the vitamin including its hydroxylated metabolite 25(OH)D, variation among samples of the same food because of animal diet, ultraviolet exposure of provitamin D sterol-containing foods, and validation of analytical methods. Decisions made during development of vitamin D food composition databases also affect the representativeness of mean values used to calculate dietary intake in a specific context. These challenges are discussed, along with the potential impact on estimation of vitamin D intake from foods. Data for naturally occurring vitamin D3 and 25(OH)D3 in animal products are summarized.