According to a research study presented in the February 2000 issue of Obstetrics & Gynecology, a low-fat, vegan diet "significantly reduced pain and PMS for many women." Painful menstrual cramping and heavy periods can be largely attributed to chemicals called prostaglandins which promote inflammation. Prostaglandins are also associated with the constriction of blood vessels, blood clotting, muscle contractions, and pain. Therefore, reducing the levels of prostaglandins also reduces the intensity and flow of a woman's menstrual cycle. Although the use of oral contraceptives has been found to reduce the production of prostaglandins, dietary changes can produce the same results by lowering a woman's estrogen levels. Lower levels of estrogen can be achieved by eating a Starch-Smart® diet and avoiding animal products and oils which raises estrogen levels, causing heavier and more painful menstrual periods.
For more details, see: Menstrual Cramping and Heavy Periods