The Best Way to Get Enough Calcium
July 17, 2007
A new study suggests that calcium from food sources may be more effective than calcium from supplements. It found that women who get most of their daily calcium from food sources have healthier bones and greater bone density, even though those who took more supplements tended to have higher average levels of calcium.
Researchers asked 183 postmenopausal women to document their diet over the course of a week, after which their bone mineral density and estrogen were tested. Women who got at least 70 percent of their daily calcium from food sources instead of supplements took in the least calcium (830 milligrams per day, on average), but higher spine and hip bone density than women consuming 1,030 milligrams of calcium per day primarily from supplement sources.
Women who got calcium in relatively even amounts from both food and supplemental sources had both the highest bone mineral density and the highest calcium intake (1,620 milligrams per day).
Calcium from dietary sources is usually more completely absorbed than calcium from supplements, which could explain the difference. Women who got getting calcium from foods also had higher estrogen levels; estrogen is needed to maintain bone mineral density. The connection between dietary calcium and estrogen is as yet unknown, although it could be the result of eating plant sources containing the hormone.
Those who got calcium from food sources might have also taken in more vitamin D, which would aid in calcium absorption.
American Journal of Clinical Nutrition May 2007, Vol. 85, No. 5, 1428-1433
Yahoo News June 27, 2007