10 strategies For Preventing Breast Cancer
1. Do not drink alcohol.
More than fifty studies have been conducted on the influence of alcohol on breast cancer risk. Meta-analyses of these studies have concluded that having one alcoholic drink per day increases risk at least 7-10%, and the risk increases further with more alcohol.1 In breast cancer survivors, drinking 3-4 alcoholic beverages per week increased the risk of recurrence by 34%.2
2. Do not smoke.
Breast carcinogens have been identified in cigarette smoke, and they are known to enter the bloodstream via the lungs and travel to breast tissue, putting smokers at risk.3
3. Do not take estrogen.
Cumulative exposure to estrogen is known to be a risk factor for breast cancer.4,5 As such, women who have used hormone replacement therapy (HRT) are at risk, and that risk increases with increasing duration of HRT.6
4. Have babies and nurse them for two years each.
Having children before the age of 24 and having multiple children are both protective against breast cancer.7 Breastfeeding also contributes to risk reduction, in part by reducing estrogen exposure - longer duration of breastfeeding confers more protection.8
5. Reduce consumption of animal protein.
Cooked meat (not just red meat, poultry as well) is known to contain breast carcinogens such as PhiP.9-11 Consuming more protein and especially dairy products raises blood levels of IGF-1, and elevated IGF-1 levels have been associated with increased in breast cancer risk in many studies.13-21 Higher fish consumption in women has also been linked to higher rates of breast cancer.12 Agricultural and industrial carcinogens, such as dioxins, accumulate in fatty tissues. Humans' primary mode of exposure to these dangerous chemicals is from meat, poultry, fish, and dairy fat.22
6. Eat lots of green vegetables, mushrooms, and onions.
Following a high-nutrient diet, as described in my book Eat to Live, protects against many chronic diseases, breast cancer included. Green vegetables and mushrooms are the most powerful anti-breast cancer foods. Take note that a vegetarian diet does not show protection against breast cancer as much as a diet rich in green vegetables, mushrooms, onions, berries, and seeds. It is the phytochemical nutrient density and diversity of the diet that offers the most dramatic protection against cancer, not merely the avoidance of meat or fat.23-27
Vegetables and fruits have been consistently associated with both reduced risk of breast cancer and improved survival of breast cancer patients.23,25,28-30 Cruciferous vegetables contain powerful anti-cancer compounds that halt the growth of breast cancer cells and promote excretion of estrogen.24,31,32 Mushrooms block tumor growth and have anti-estrogenic activity - regular consumption of mushrooms - as little as one mushroom per day – has been shown to decrease breast cancer risk by up to 60-70%.26,27,33 Organosulfur compounds in onions and garlic also prevent the development of cancers by detoxifying carcinogens, halting cancer cell growth, and preventing tumors from obtaining a blood supply.34
7. Use supplements wisely.
Take a multivitamin that does not contain folic acid, maintain healthy vitamin D levels, and take at least 100 mg of DHA daily. Synthetic folic acid in multivitamins and prenatal vitamins has been associated with increased risk of breast cancer, whereas folate from natural food sources is associated with decreased risk.35-38 Three-quarters of women who have breast cancer are vitamin D deficient, and maintaining sufficient blood vitamin D levels can decrease risk of breast cancer by up to 45%.39,40 Omega-3 fatty acid consumption is associated with reduced cancer incidence. The omega-3 DHA has anti-inflammatory effects and also blocks tumor angiogenesis and tumor cell growth.41-43
8. Use one tablespoon of ground flax seeds or chia seeds daily.
Flax seed lignans have anti-estrogenic effects and also inhibit cell growth in
9. Don't grill or fry foods.
Steaming vegetables or making vegetable soups should be the major extent of cooking. High temperature dry cooking produces compounds known to be carcinogenic – acrylamides (formed in starchy foods) and heterocyclic amines (formed in meats).46-48
10. Exercise at least three hours a week and maintain a lean body with little body fat.
An analysis of 73 different studies concluded that women with high levels of physical activity reduced their risk of breast cancer by 25%.49,50 Maintaining a healthy weight is also extremely important, since 17% of breast cancer cases can be attributed to
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