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Breast Health Basics

Michael T. Murray, ND, is widely regarded as one of world’s leading authorities on natural medicine. Here, he answers questions about reducing breast cancer.

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Q: I have fibrocystic breast disease. Is there anything I can do to reduce my risk of developing breast cancer?

A: Breast cancer is a major fear for many women these days. The fear comes, in large part, from the fact that many have watched someone close to them succumb to this disease. Fortunately, there is much that can be done through diet and lifestyle to dramatically reduce the risk of breast cancer.

One of the risk factors for breast cancer is fibrocystic breast disease (FBD). It is not as significant a factor as the major breast cancer risk factors, which include family history, early onset of periods, and late or no first pregnancy. However, it does carry with it increased risk, and is a major reason why many women are subjected to mammograms, as the lumps of FBD are not easily distinguished from breast cancer.

Fiber and Probiotics

Breast disease (both breast cancer and FBD) has been linked to a low-fiber diet and constipation. In one interesting study published in the medical journal The Lancet, researchers noted an association between abnormal cell structure from breast cells and the frequency of bowel movements; women who had fewer than three bowel movements per week had a risk of FBD that was 4.5 times greater than women who had at least one a day. This association is probably due to the absorption of gut-derived toxins, and a less than ideal bacterial flora in the large intestine. The take away message is to promote effective elimination and detoxification by keeping things moving. A high-fiber diet is critical in this goal.

One of the key ways in which the body gets rid of toxic chemicals as well as hormones like estrogen is by attaching glucuronic acid to them in the liver and then excreting this complex in the bile. Beta-glucuronidase is a bacterial enzyme that breaks the bond between the excreted estrogen and glucuronic acid. When beta-glucoronidase breaks the bond, the freed estrogen is available to be reabsorbed back into the body instead of being excreted. An elevated beta-glucuronidase activity is associated with an increased risk for various cancers, particularly hormone-dependent cancers like breast and prostate cancer.

There are some easy ways to reduce the activity of this bacterial enzyme and increase the excretion of estrogen. The No. 1 simple, yet effective, way is to increase the intake of high-fiber foods, especially vegetables and legumes. Women on a vegetarian diet excrete two to three times more estrogens than women on an omnivorous diet (who also reabsorb more estrogens). Furthermore, omnivorous women have a 50% higher average level of free estrogen reabsorbed from the intestinal tract. This difference is most likely because they eat less fiber than women on a vegetarian diet.

See also The Complete Guide to Breast Health

A higher intake of dietary fiber is also associated with a more favorable gut flora. In women with FBD or concerned about breast cancer, I would recommend also taking a probiotic supplement. Probiotic supplementation has been shown to lower the activity of beta-glucuronidase and may also help improve bowel function—two very important goals in promoting breast health. Take 5 to 10 billion colony forming units (CFU) of Lactobacillus and/or Bifidobacteria daily.

Increase Phytoestrogens

Vegetarian diets are also high in phytoestrogens that are able to bind to the same cell receptors as the estrogen your body produces. That’s a good thing, because when phytoestrogens occupy the “parking places,” estrogen can’t produce effects on cells. By competing with estrogen, phytoestrogen causes a drop in estrogen effects, and are thus sometimes called antiestrogens. Great sources of phytoestrogens include soy and soy foods, ground flaxseeds, and nuts and seeds. In fact, taking 1 tablespoon of ground flaxseeds daily is a good recommendation for breast health

Fish Oils

Fish oils provide the long-chain omega-3 fatty acids EPA and DHA. Women with the highest ratio of the long-chain omega-3 fatty acids EPA and DHA to omega-6 fatty acids (the omega-3:omega-6 ratio) had a 67% reduced risk of breast cancer, making it one of the most powerful nutritional factors in preventing breast cancer. Take 1,000 to 3,000 mg of EPA and DHA from high-quality fish oils.

Cabbage Family Vegetables

Cabbage family vegetables, such as broccoli, cauliflower, cabbage, and kale, contain anticancer phytochemicals known as glucosinolates that are potent stimulators of natural detoxifying enzymes. Studies have shown that increasing the intake of cabbage family vegetables, or taking the chief glucosinolates indole-3-carbinol (I3C) or DIM as a dietary supplement, significantly increased the conversion of estrogen from cancer-producing forms to non-toxic breakdown products. Adding one or two servings daily of cooked cruciferous vegetables to your diet or taking supplements containing I3C (400 mg daily) or DIM (2 mg/kg/day) shifts the ratio from bad to good estrogen breakdown products.

Chaste Berry (Vitex Agnus-Castus)

One of the most useful herbal remedies for breast health is chaste berry (also called vitex). Evidence that it can be effective in the treatment of FBD has been reported in several studies. I recommend vitex only for women who are also showing other signs of PMS (mood swings, depression, irritability, etc.). The usual dosage (often standardized to contain 0.5 percent agnuside) in tablet or capsule form is 175 to 225 mg per day.

Green Tea

Drink more green tea or take a green tea extract. Population-based studies have shown that green tea consumption reduces breast cancer risk. For example, studies have suggested that breast cancer rates are lower in Japan in part because people there typically drink about 3 cups of green tea daily. To achieve the same degree of protection from supplements containing green tea extract would mean taking a daily dose of 300 to 400 mg.

Factors that may increase risk Factors that may lower risk:
• Meats 
• Fish
• Total fat 
• Whole grains
• Saturated fats 
• Soy and other legumes
• Dairy Cabbage
• Refined sugar 
• Vegetables
• Excess calories 
• Nuts
• Alcohol 
• Fruits

Exercise and Breast Cancer Risk: New Findings

Previous studies have demonstrated that physical activity reduces breast cancer risk, but questions remained: how often, how long, and how intense does physical activity have to be to provide benefits? Do women with all body types experience a reduced risk? Do women of all ages benefit?

A study published this year in the journal Cancer shows that even mild exercise, before or after menopause, may reduce the risk of developing breast cancer. The study included 1,504 women with breast cancer and 1,555 women without breast cancer ranging in age from 20 to 98 years old. Women who exercised, either during their reproductive or postmenopausal years, had a reduced risk of developing the disease. Women who exercised 10 to 19 hours per week experienced the greatest benefit with an approximate 30% reduced risk, although risk reductions were observed at all levels of intensity. One caveat—substantial weight gain, particularly after menopause, seemed to negate these benefits. Overall, the findings indicate that women of any age can reduce their breast cancer risk by doing some type of exercise and maintaining their weight.

Meet Our Expert

Michael T. Murray, ND, is widely regarded as one of world’s leading authorities on natural medicine. Murray has written more than
20 books including the bestselling Encyclopedia of Natural Medicine. Go to for more information.