1. Maintain a healthy body weight (BMI less than 25) throughout your life. Weight gain in midlife, independent of BMI, has been shown to significantly increase breast cancer risk. Additionally, and elevated BMI has been conclusively shown to increase the risk of post-menopausal breast cancer.
2. Minimize or avoid alcohol. Alcohol use is the most well established dietary risk factor for breast cancer. The Harvard Nurses' Health study, along with several others, has shown consuming more than one alcoholic beverage a day can increase breast cancer risk by as much as 20-25 percent.
3. Consume as many fruits and vegetables as possible. Eat seven or more servings daily. The superstars for breast cancer protection include all cruciferous vegetables (broccoli, cabbage, brussels sprouts, cauliflower) ; dark leafy greens (collards, kale, spinach) ; carrots and tomatoes. The superstar fruits include citrus, berries and cherries. Note: it is best to eat cruciferous vegetables raw or lightly cooked, as some of the phytochemicals believed to offer protection against breast cancer are destroyed by heat.
4. Exercise regularly the rest of your life. Many studies have shown that regular exercise provides powerful protection against breast cancer. Aim for 30 minutes or more of moderate aerobic activity (brisk walking) five or more days a week. Consistency and duration, not intensity, are key!
5. Do your fats right! The type of fat in your diet can affect your breast cancer risk. Minimize consumption of omega-6 fats (sunflower, safflower, corn and cottonseed oils), saturated fats and trans fats. Maximize your intake of omega-3 fats, especially from oily fish (salmon, tuna, mackerel, sardines, lake trout and herring). Consume monounsaturated oils (canola, olive oil, nuts/seeds, avocados) as your primary fat source, as these foods have potential anticancer properties. Specifically, canola oil is a good source of omega-3 fats; extra virgin olive oil is a potent source of antioxidant polyphenols, including squalene; and nuts and seeds provide you with the cancer protective mineral, selenium.
6. Do your carbs right! Minimize consumption of the high glycemic index, "Great White Hazards" - white flour, white rice, white potatoes, sugar and products containing them. These foods trigger hormonal changes that promote cellular growth in breast tissue. Replace these "wrong" carbs with whole grains and beans/legumes. Beans/legumes because of their high fiber and lignan content are especially special.
7. Consume whole food soy products regularly, such as tofu, tempeh, edamame, roasted soy nuts, soy milk and miso. Only consume organic, non-GMO (genetically modified) soy. Epidemiologic studies have shown a positive association between soy consumption and reduced breast cancer risk.
8. Minimize exposure to pharmacologic estrogens and xeno-estrogens. Do not take prescription estrogens unless medically indicated. Lifetime exposure to estrogen plays a fundamental role in the development of breast cancer. Also avoid estrogen-like compounds found in environmental pollutants, such as pesticides and industrial chemicals. Buy organic produce if you can afford it; otherwise, thoroughly wash all non-organic produce. Minimize exposure to residual hormones found in non-organic dairy products, meat and poultry.
9. Take your supplements daily. A multivitamin, 500-1,000 mg of vitamin C in divided doses, 200-400 IUs of vitamin E as mixed tocopherols, and pharmaceutical grade fish oil. Also take 200 mcg of the mineral selenium or eat one to two Brazil nuts as an alternative. If you have a chronic medical condition or take prescription drugs, consult your physician first.
10. Maintain a positive mental outlook. Engage in self-nurturing behaviors regularly. Develop rich, warm and mutually beneficial relationships with family and friends. Get adequate sleep (7-8 hours per night). The mind-body associations with breast cancer are significant.