Milk curbs osteoporosis.

A few extra 8-ounce glasses of skim milk daily may be better than calcium supplements for postmenopausal women, a new study indicates. Osteoporosis, or bone loss, accounts in large part for both the frequency of hip and spine fractures in the elderly and the slowness with which their bones heal. Though studies have shown that calcium carbonate supplements can slow or curb bone loss in postmenopausal women, there has been some question about whether good old milk -- whose calcium is delivered to the body in a noncarbonate form -- might not work as well.

Robert Recker and Robert Heaney of the Creighton University School of Medicine in Omaha, Neb., compared the two in a year-long study of 22 healthy postmenopausal women. In the February AMERICAN JOURNAL OF CLINICAL NUTRITION, they report that milk retards bone loss as effectively as carbonate supplements. Moreover, unlike the supplements, it does not suppress bone renewal.

Explains Recker, "This renewal process exists to replace the skeletal tissue that has aged." It is important, he says, because "the skeleton is crystalline, and like any crystalline substance, when it's subjected to submaximal strains, it can fall, or break." He says the natural bone remodeling process removes aged tissue prone to cracking and tissue that may already have acquired microcracks. Recker found that while did not seem to affect the natural bone remodeling rate, calcium carbonate supplements suppressed it by 25 to 30 percent.

Recker says his research shows that bone loss can be halted in postmenopausal women consuming about 1,500 milligrams of calcium daily. However, he adds, that's far more than most women get. "One quarter of all adult white women in this country get 300 mg per day or less," he says," and the median dietary intake for women in adult life is close to 500 mg -- well below the current recommended daily allowance of 800 mg."