Calcium for PMS.

Calcium carbonate--an inexpensive, widely available supplement--seems to lessen the symptoms of premenstrual syndrome (PMS), says a study funded by SmithKline Beecham, maker of the calcium carbonate antacid/supplement Tums.

Susan Thys-Jacobs and colleagues at Columbia University in New York studied 466 premenopausal women with moderate-to-severe PMS at 12 locations around the U.S. Each woman was randomly assigned to take either 600 mg of calcium carbonate or a (calcium-flee lookalike) placebo twice a day for three menstrual cycles.

By the third cycle, the calcium-takers reported a 48 percent reduction in overall symptoms during the two weeks before their menstrual periods. The placebo-takers reported only a 30 percent reduction. The symptoms included mood swings, depression, anxiety, anger, breast tenderness, water retention, food cravings, cramps, and headaches. The only symptoms that didn't improve were insomnia and fatigue.

The study didn't look at other doses or forms of calcium. "I would guess that any would work, but you'd have to take a lot of tablets,' says Thys-Jacobs. Calcium carbonate is the most-concentrated form.

"It's better to take calcium with meals," she adds, "because it's better absorbed and because there's less risk of kidney stones."

Amer. J. Obstet. Gynecol. 179: 444, 1998.