Vitamin D, calcium and prevention of breast cancer: A review

Several recent epidemiologic and experimental studies have suggested that d ecreased calcium and vitamin D intake and high dietary fat are associated w ith mammary gland carcinogenesis. Complete reduction or elimination of huma n exposure to environmental factors such as high-fat diets is inherently di fficult to implement. Recent studies have begun to evaluate a possible role for increased dietary calcium and vitamin D in reducing the risk of coloni c and mammary cancers, even in the presence of a high-fat diet. Studies fro m our laboratory recently found that decreased dietary calcium and vitamin D in a high-fat diet induced adverse changes in the mammary gland and sever al other organs, which were reversed by increasing dietary calcium and vita min D; the findings further suggest a possible role for increased dietary c alcium and vitamin D in the chemoprevention of these cancers.