Women following a low-fat, vegetarian diet can expect significant reductions in menstrual pain and PMS symptoms, according to a new study conducted by the Physicians Committee for Responsible Medicine (PCRM) in conjunction with the Department of Obstetrics and Gynecology at Georgetown University Medical Center.

“Approximately 10 percent of all women suffer such severe pain during their menstrual cycles that they’re forced to miss work and other activities,” says Dr. Neal D. Barnard, PCRM president and nutrition researcher.

Among the main causes of their pain are chemicals called prostaglandins, made from traces of fat stored in cell membranes. Barnard and his colleagues hypothesized that if women reduced their fat consumption, they’d also decrease their estrogen levels, which would in turn reduce cell growth and prostaglandin production.

“Our goal was to smooth out the hormonal roller coaster many of them experience each month,” said Barnard, who had noticed former patients overcome terrible menstrual pain after changing to a low-fat diet.

“We also hypothesized high-fiber diets, especially vegetarian diets, would increase a protein in the blood called sex-hormone binding globulin, which binds and inactivates estrogen in the bloodstream until it is needed. In essence, it calms down the hormone swings,” said Barnard.

Results for some of the women participating in the study were dramatic. Besides a decrease in the intensity of menstrual pain, the women experienced an average of 1.5 fewer days of pain each month.

“Their pain was gone or dramatically reduced, something they had not experienced for years. If they needed any pain medicine at all, they needed much less than before.”

Many women also experienced a significant relief from PMS symptoms, most notably with water retention and concentration problems.