Calcium May Cut PMS Risk

A diet rich in calcium and vitamin D appears to reduce the risk of developing premenstrual syndrome (PMS) by as much as 40%, researchers report.

Although most women experience mild PMS, including bloating, breast tenderness and headache, symptoms in approximately 20% of women are severe enough to interfere with daily activities.

The Study

Researcher Elizabeth R. Bertone-Johnson, an assistant professor of epidemiology at the University of Massachusetts, Amherst, and her team collected data on women who had PMS as well as those who did not. "We compared the dietary intake of calcium and vitamin D in 1,057 women in the Nurses Health Study II who had developed PMS over a 10-year period with 1,968 women who did not develop PMS," she says.

The comparison showed that calcium intake had a profound effect on whether the women developed PMS. "We found that women with the highest intakes of vitamin D and calcium from food sources did have a significantly reduced risk of being diagnosed with PMS," reports Bertone-Johnson.

The greatest benefit was in women who consumed approximately 1,200 milligrams (mg) of calcium and 500 international units (IU) of vitamin D per day—the equivalent of four servings of skim or low-fat milk, fortified orange juice or low-fat dairy foods, such as yogurt. Their risk of being diagnosed with PMS was approximately 40% lower than women who consumed these foods only once a week, she says.

Bertone-Johnson's study confirms earlier studies that found calcium supplements and vitamin D, which aids the absorption of calcium, may reduce both the occurrence and severity of PMS

Levels of calcium and vitamin D fluctuate across the menstrual cycle. Increasing calcium and vitamin D intake might help PMS by affecting estrogen levels during menstruation, Bertone-Johnson speculates.

The Reaction

However, some experts view the finding with caution. "I don't think this is going to explain all women who have PMS," says Ellen W. Freeman, a research professor in the department of obstetrics and gynecology and in the department of psychiatry at the University of Pennsylvania's School of Medicine, Philadelphia "I am very skeptical that slow calcium intake) is a major cause of PMS."

However, Freeman believes that for most women, increasing calcium and vitamin D intake can't hurt although it might not reduce the occurrence or severity of PMS. "Overall, in this country women don't have enough calcium," she notes.

Another expert finds the report interesting, but cautions that it does not apply to all premenstrual problems. "The findings are very interesting and very positive for treating disorders in women," says Dr. Margaret Spinelli, an associate clinical professor of psychiatry at Columbia University in New York City.

Spinelli notes that one should not confuse PMS with premenstrual dysphoric disorder (PMDD-a condition that affects up to 5% of women and causes symptoms similar to major depression. "That's more serious," she says. "PMS has more to do with physical symptoms ... But if you can find something to relieve these symptoms without taking other medication, that's a benefit."