Certain foods appear to make endometriosis more likely. Accoding to researchers at the Harvard School of Public Health, women who have two or more cups of caffeinated coffee (or four cans of cola) per day were found to be twice as likely to develop endometriosis as other women. Why caffeine has this effect is unknown. [19]

Foods tainted with certain chemicals appear to encourage the implantation of cells in the abdomen. Polychlorinated biphenyls (PCBs) were commonly used in electrical equipment, hydraulic fluid and carbonless carbon paper; and organochlorine pesticides have commonly been used in agriculture. In 1992, German researchers found that women with high blood levels of PCBs had a higher prevalence of endometriosis [20].

These chemicals presumably do their dirty work by weakening your immune defenses. Indeed, the natural killer cells and other white blood cells that are supposed to maintain a constant lookout for any hormonal cells have been shown to be less effective in women with endometriosis [17]. In addition, some organochlorines mimic the effects of estrogens [14,21].

These toxins tend to accumulate in animal fat, and the major route of human exposure is through food, particularly fish. They also show up in meats and dairy products.[14] Chickens, cattle, pigs, and other animals are fed grains treated with pesticides and sometimes contaminated with other organochlorines, and these compounds tend to concentrate their muscle tissues and milk. While there may be organochlorine pesticide residues on nonorganic fruits or vegetables, they are less concentrated and can at least partially be removed by washing or peeling. Organic produce is grown without chemical pesticides.

To measure the concentration of organochlorines in awoman's body, researchers sometimes check samples of breast milk. Breast tissue is a natural target for chemicals dissolve into fat, and in fat, during breast-feeding, a woman can excrete up to half of all the dioxin she has accumulated in her body tissues. [21] Unfortunately, the recipient of these chemicals is the nursing baby.

A vegetarian diet has obvious advantages. By avoiding fish, other meats, and cow's milk, you avoid the foods that harbor most organochlorines. Indeed, researchers have found that vegetarian women have much lower levels of pollutants in their breast milk, compared to other women [22]. The earlier in life a plant-based diet is begun, the better.

Happily, bans on some of these compounds have caused exposures to decrease since 1970s, although the amount in your body drops only slowly.

Some women with endometriosis improve on their own, although most find that their symptoms continue or gradually worsen. Medical treatments rely on anti-inflammatory painkillers and hormone treatments designed to shrink endometrial tissues: danazol, gestrinone, GnRH agonistic analogues, progesterone derivatives, and progesterone-estrogen combinations.

Surgical treatments include removing cell clumps, severing pain nerves, and even hysterectomy, sometimes with removal of the ovaries. Surgery to remove endometrial cells has about the same effectiveness as drug treatments, but both are usually temporary measures, as they do not reliably eliminate all of the troublesome cells [23,24].

Dietary treatment is based on the fact that, whatever causes endometriosis to start, estrogen keeps it going. Without estrogen, the clumps of ells do not grow each month adn soon wither away. This means that the same dietary approach that reuces estrogens can also be used for endometriosis. In my discussions with gynecologists who have tried this approach, it is clear that, for some patients at least, it can make a big difference.

Ronald Burmeister, M.D., a gynecologist in Rockford, Illinois, describes the case of a twenty-four-year-old woman who had had terrible menstrual pain every month since her periods began. She had had laparoscopic surgery twice, but her pain continued. She had tried birth control pills, but they caused depression and other side effects. Hormone-blocking medications were helpful, but the medicine was expensive and, in any case, could be prescribed for only six months without an increased risk of osteoporosis. After it was stopped, her pain returned. A progesterone derivative helped some but did not abolish the pain. One of her doctors recommended hysterectomy, but she wanted to avoid such a drastic solution.

Dr Burmeister suggested a hormone-balancing diet. Using low-fat, purely vegetarian foods, his patient could reduce her hormone shifts, and unlike medicines or a hysterectomy, it would not interfere with her efforts to get pregnant. He gave her a set of recipes and recommended several books for further information.

Within three month she was noticeably better, and at six months her pain was gone. She stopped the progesterone derivative and set about seeing if she could become pregnant.

Based on this success, Dr Burmeister made the same recommendation in three other cases and found that it was helpful in reducing pain. One patient reported that if she deviated at all from the diet, by having some dairy products or a bit of chicken, her pain came right back, much like skipping one or two pills can make a prescription fail.

No one has yet conducted a clinical study on the use of a low-fat, vegetarian diet for endometriosis. That should change because, unlike hormone treatments, it does not interfere with efforts to conceive. It is also cheap and safe and provides many other health benefits, too.

Aerobic exercise also helps. Women who run, jog, or work out for two hours per week have only half the risk of endometriosis, compared to other women. The reason, presumably, is the well-established ability of exercise to reduce hormone activity. In fact, women who exercise strenuously and consistently sometimes miss periods altogether[16] Exercise also strengthens the immune system, making you better able to eliminate errant cells.

Natural progesterone can also be used to oppose estrogen in endometriosis. It is typically used from day eight to day twenty-six of the monthly cycle (counting the first day of bleeding as day one), using up a two-ounce jar each month. This delivers about 40-50 mg per day. Normally, this dose is continued for about four months, then the dose is reduced as the pain diminishes.

If endometriosis is caused by an immune system failure to recognize and eliminate out-of-place cells, immune-boosting foods might help prevent it.

You already want to reduce the amount of fat you eat in order to keep your estrogen level lower. Getting away from fat also helps your immunity [25]. Researchers have found that fatty foods impair the function of white blood cells. This is true for any kind of fat — animal fat or vegetable oil It is also true of cholesterol. When researchers add cholesterol to white blood cells in the test tube, they find that their immune strength is diminished [26-28]. As we saw in chapter 2, a low-fat, zero-cholesterol diet simply means getting your nutrition from plant sources, rather than animal sources, and keeping added oils to a minimum.

Researchers have studied the effect of different diets on the natural killer cells that seek out and destroy abnormal cells, and it is clear that getting away from fat and cholesterol makes a big difference. When blood samples are taken from volunteers and th ability of their natural killer cells to destroy abnormal cells is tested, vegetarians do twice as well as their omnivore counterparts[29].

You can get an extra immune boost from beta-carotine, found in orange vegetables, such as carrots and sweet potatoes, from vitamin E, found in grains and beans, and from vitamin C, which is in many fruits and vegetables.