Learn more about Vitamin A & D
A study published in The American Journal of Clinical Nutrition found that taking vitamin D supplements and calcium substantially reduces all-cancer risk in post menopausal women. The researchers found that the higher the levels of vitamin D in the blood, the lower the relative risk of developing cancer. Another study suggests that women who consume more calcium and vitamin D may be less likely to develop breast cancer before menopause (Canadian Cancer Society, 2007) (Lappe et al., 2007).
Vitamin D’s major biological function is to maintain normal blood levels of calcium and phosphorus. With aging, less vitamin D is converted to its active form, and a deficiency can occur in older men and post-menopausal women. In a review of women hospitalized for hip fractures due to osteoporosis, 50 percent were found to have signs of vitamin D deficiency (LeBoff et al., 1999). Caffeine can increase bone loss, but increasing calcium and vitamin D intake may counteract this effect.
Canadian Cancer Society. Canadian Cancer Society Announces Vitamin D Recommendation June 08, 2007 www.cancer.ca
Lappe, J.M., Travers-Gustafson, D., Davies, M.K., Recker, R.R. & Heaney, R.P. (2007, June). Vitamin D and calcium supplementation reduces cancer risk: results of a randomized trial. American Journal of Clinical Nutrition, Vol. 85, No. 6, 1586-1591.
LeBoff, M.S., Kohlmeier, L., Hurwitz, S., Franklin, J., Wright, J., Glowacki, J. (1999).Occult vitamin D deficiency in postmenopausal US women with acute hip fracture. J Am Med Assoc, 251:1505-11.
The Office of Dietary Supplements. (2007, Sept 19). http://ods.od.nih.gov/factsheets/vitamind.asp.