Every month, like clockwork, half of humanity suffers from a variety of physical and mental symptoms associated with their menstrual periods . Told for decades that premenstrual syndrome (PMS) and menstrual cramps were “all in their heads,” women suffered their “imaginary” discomforts so frequently that one of four routinely loses time at work or school. Left on their own by medical science, women generally did their best to treat themselves with herbal and other home remedies, over-the- counter medicines and exercises. As science and medicine have begun to include more women in their ranks, a genuine physical basis for PMS and other menstrual symptoms has been uncovered/the culprit is the body’s production of prostaglandins, produced by fat stored in uterine cell walls. The body’s fluctuating hormones, like progesterone and estrogen, stimulate prostaglandin levels. Estrogen, for example, causes the uterine wall to grow thicker, producing greater amounts of prostaglandins. The greater the body’s supply of estrogen, the higher the level of prostaglandin, and the greater the menstrual discomfort. A study conducted at Georgetown University has found that estrogen levels can be reduced by eating a low-fat, vegetarian diet high in fiber. When women in the study ate such a diet they experienced less severe menstrual symptoms , and for less time. When the women ate their normal, omnivorous diets, their symptoms of menstrual distress were longer and more severe. The University researchers studied 33 women, age 22 to 48, who had suffered from significant menstrual pain. For the first two months of the study the women ate a low-fat vegan diet, which included no animal foods, arid fewer than 10% of calories from fat. During the second two study months, the women ate their normal, unrestricted diets. The researchers monitored the women’s levels of hormones, their weights and the intensity and duration of their menstrual discomfort. The researchers found that the women experienced about 4 days of discomfort on their regular diets, but only 2.7 days after 2 months on the vegan diet. They also reported lower levels of pain intensity, less water retention, lower cholesterol levels and lower weight as vegetarians. The researchers theorize the low-fat, high- fiber diet works in two ways: first lowering the body’s initial production of estrogen, then by increasing the body’s ability to excrete excess estrogen. Based on information in: Obstetrics & Gynecology 200tt 95 245-250