Making no bones about calcium supplements.

An estimated 250,000 hip fractures occur each year in the United States as the result of weakened bone structure in older women. Even a 20 percent reduction in such fractures would save as much as $2 billion--and an inestimable amount of pain and suffering.

Such savings are not only possible but easily achieved, as demonstrated in a recent New England Journal of Medicine report. By taking 1,000 mg of calcium a day in addition to what their food provided, 61 New Zealand women reduced their normal bone loss by an average of 43 percent. By comparison, a control group of 61 women had gotten only about 750 mg of calcium from their normal diet. These women continued to lose about one percent of their bone mass each year because of reduced estrogen levels after menopause.

This study was conducted at the University of Auckland, New Zealand, on 122 women who were at least three years beyond menopause. Researchers randomly chose half to receive the supplement while the other half received a pill identical in appearance that contained no calcium. The normal diets of all participants provided about 750 mg of calcium daily--about twice as much as most women in this country regularly consume.

Although it has been assumed that taking extra calcium would reduce the risk of fractures in postmenopausal women, previous studies have produced equivocal results. Of the 43 such studies in the past 15 years, 27 showed a definite benefit from calcium supplements.

In a related NEJM editorial, Dr. Robert P. Heaney of Creighton University, Omaha, Neb., said that the time has come to recommend calcium supplements for all older women. "Although we do not know everything we would like to know about this issue, we know enough to act now," he wrote.

Dr. Heaney also said that doctors should encourage women to take both calcium and vitamin D for additional protection against bone loss. He recommends at least 1,000 mg--and preferably 1,500--of calcium daily, with 400-800 international units of vitamin D.

Many foods contain calcium. A quart of milk, for example, contains 1,200 mg altogether. Broccoli and other dark-green vegetables are also rich in calcium, as are the edible bones of sardines and other bony fish. Look for foods whose labels show them fortified with calcium. Some antacid tablets, such as Tums, contain calcium in the form of calcium carbonate.