Results from a study completed at Washington University in St. Louis (American Journal of Clinical Nutrition, May 2007) report that women who get most of their calcium from food have higher bone mineral density than women receiving their calcium from supplements. The study involved 183 postmenopausal women, who were nonsmokers and not taking medications that would increase their estrogen levels. They recorded their 7-day daily intake of food and supplements containing calcium. A review of the data divided the women into 3 groups: those getting 70% of their calcium from food; those getting 70% of their calcium from supplements; and those whose calcium intake was divided evenly between supplements and diet. The women who received their calcium from food, while it averaged only 850 mg/day, had higher bone mineral density than the women taking supplements of 1,033 mg/day. The women who divided their calcium intake by food and supplements had the highest bone mineral density and the highest daily calcium intake at 1,620 mg/day. Calcium affects the metabolism of estrogen, and the higher levels of calcium may have increased the bone mineral density for the third group. Calcium absorption is based on the amount of calcium consumed at one time, the type of supplement used, and the level of vitamin D systemwide. The recommended daily dose of calcium is 1,200 to 1,500 mg/day, and 800 to 1,000 IU of vitamin D daily.
(Source: Harvard Women’s Health Watch, September 2007)
