According to the World Cancer Research Fund in 2009, 40% of all cancers could be prevented by changes in diet and lifestyle and only 5% are actually due to a genetic disposition.
Recommendations from the WCRF include avoiding sugary drinks and limiting consumption of foods high in added sugar, low in fibre or high in salt, eating more of a variety of vegetables, fruits, wholegrains and pulses (which are phytoestrogens and balance hormones) such as beans, and limiting consumption of red meats and avoiding processed meats.
Maintain a healthy body weight
Stay as lean as possible without becoming underweight. Putting on 1.5 stones after menopause increases breast cancer risk by 18 % and women who shed 1.5 stone after the menopause cut breast cancer risk by more than 50%.
Reduce alcohol
Limit alcoholic drinks to no more than one a day for women.
Exercise
Many studies have shown that taking regular exercise reduces the risk of breast cancer. In fact, walking for just half an hour a day has been shown to halve the risk of developing breast cancer. And one large study of over 200,000 women followed for 6.5 years showed that all types of exercise cut the risk of breast cancer.
Get more Vitamin D
Research over the last few years has also shown how important having good levels of vitamin D are in relation to the breasts.
Vitamin D promotes apoptosis, which is cell death or cell suicide. The process of apoptosis is very important because it is your body’s way of eliminating unhealthy cells and without this process those old or unhealthy cells could continue to survive. Vitamin D has also been shown to stop the multiplication of malignant breast cells and an article in the American Journal of Public Health commented that vitamin D can halve the risk of developing cancer. For a home finger prick blood test for vitamin D go to www.naturalhealthpractice.com.
Eat less red meat
One other aspect that was highlight in the WCRF factors is red meat. We know that eating more than one and a half servings (4.5 ounces) of red meat can double the risk of breast cancer compared to 0.75 servings a week. According to research the problem is certain carcinogenic chemicals which are formed when the meat is cooked. These are called heterocyclic amines (HCAs) and they increase the risk of both breast and bowel cancer. They are only found in cooked muscle meat (which includes not only meat but also chicken and fish but would not be found in other animal proteins like eggs) and the higher the temperature of the cooking the more of them are formed so frying, grilling and barbecuing produces the largest amounts of HCAs. Stewing, boiling and poaching are done at much lower temperatures and produce insignificant amounts of HCAs
Increase your fruit and vegetable intake
Increasing your fruit and vegetable intake is important generally but there is one group of vegetables that are really important for prevention of breast cancer. These are the cruciferous vegetables and include broccoli, Brussels sprouts, cabbage and cauliflower. They contain a substance called indole-3-carbinol which helps your body eliminate excess oestrogen. (Not all breast cancers are dependent on oestrogen but many are so you want your body to detoxify oestrogen efficiently). Just 1.5 cups of these vegetables a day can reduce your risk by 25%.
Phytoestrogens
In the West, breast cancer affects 133 women per 100,000 whereas in Asian countries, it is more than three times lower at 39 women per 100,000.
Research has shown that a diet high in soya is associated with a 14% reduction in risk of breast cancer.(Martinez ME et al, J Natl Cancer Inst, 2006, 98, 430-431) Two of the best soya foods for breast health are tofu and miso. (Qin LQ et al, 2006, J Nutr Sci Vitaminol (Tokyo), 52, 6, 428-36)
Include linseeds in your diet
Linseeds (flaxseeds) contain lignans which again help the successful detoxification of oestrogen through the digestive system (Haggans CJ et al, 2000, Cancer Epid Bio Prev, 9, 719-725). Try to include 1 tablespoon of ground linseeds (flaxseeds) a day; this can be sprinkled on porridge, for instance.
Breast Cancer and Dairy Foods
There are two schools of thought on the impact of dairy foods on the risk of developing breast cancer or stopping a recurrence. One is that all dairy foods should be eliminated completely, the other is that eating dairy foods does not make any difference to the risk.
What does the evidence show? We know that there is nearly a four times difference in the incidence of breast cancer between Western women (133 per 100,000) and Asian women (39 per 100,000) and in the East the women eat very little (if any) dairy foods. They also eat more of other foods that in the West we don’t eat as much of such as phytoestrogens, oily fish, seaweed.
Many studies have tried to answer this question about dairy and breast cancer and the results are not clear. Some research has said there is ‘no evidence to support a significant link between intake of dairy products and breast cancer risk’ (Al Sarakbi W et al, 2005, Int J Fertil Womens Med, 50, 6, 244-9 and Alvarez-Leon EE et al, 2006, Br J Nutr, Supp1, S94-9) while other research suggests that meat is most associated with breast cancer risk, followed by milk and then cheese (Ganmaa D, Sato A, 2005, The possible role of female sex hormones in milk from pregnant cows in the development of breast, ovarian and corpus uteri cancers, Med Hypotheses, 65, 1028-37) so the link may be animal fat rather than just dairy per se. The difficulty in getting a straight answer can also be due to the fact that it is not easy to isolate just one part of the diet and say whether there is a cause and effect. We eat a variety of foods and we are also exposed to substances from the environment such as toxins and xenoestrogens (see page 00) and there are lifestyle issues to consider such as stress, exercise, smoking and alcohol.
My concern is that dairy products naturally contain a substance called IGF-1 (insulin-like growth factor) but the levels are high in milk from pregnant cows. As the name implies it is designed to stimulate growth and as humans we produce it in childhood to help us grow. Unfortunately IGF-1 is known to stimulate cells to divide and multiply and has been implicated in not only breast cancer, but also lung, colon and prostate. IGF-1 also prevents cell death (apoptosis), which is a safety mechanism that causes a cell to die at the appropriate time allowing new cells to develop. If apoptosis is prevented then it could mean that abnormal cells are able to survive and flourish.
InAmerica, cows are given recombinant bovine growth hormone (rBGH) which not only increases milk production by up to 20% but also increases the levels of IGF-1 by up to five times. rBGH is banned in the EU so we don’t give this to cows in theUKbut dairy products imported from theUScan contain it.
My other concern is that nowadays cows are milked while they are pregnant. During pregnancy, levels of hormones like oestrogen are much higher so the dairy foods that we eat will contain high amounts of this hormone, which is a risk factor for breast cancer. Also, oestrogen will be even higher when the cow is milked during the later stages of pregnancy. Our milk nowadays is not the same as years ago; it is produced on a much larger commercial scale. In my opinion you do not want to add even more oestrogen into our bodies along with the xenoestrogens we are exposed to from the environment (see page 00). It is estimated that milk from a cow in the late stages of pregnancy can contain up to 33 times more oestrogen than milk from a non-pregnant cow and as one study stated in relation to the risk of not breast but ovarian and womb cancers ‘among dietary risk factors, we are most concerned with milk and dairy products, because the milk we drink today is produced from pregnant cows, in which estrogen and progesterone levels are markedly elevated’. (Ganmaa D, Sato A, 2005, The possible role of female sex hormones in milk from pregnant cows in the development of breast, ovarian and corpus uteri cancers, Med Hypotheses, 65, 1028-37)
You don’t need to eat dairy foods to stay healthy and if you are worried about where you will get your calcium from then see the chart of calcium-rich non-dairy in Appendix X. Also, when dairy is eaten as cheese it has an acidic effect on your body and will cause calcium to be leeched from your bones so this is not a good form of dairy after the menopause anyway. My suggestion would be that if you are going to eat dairy foods concentrate on taking them in the form of organic live plain yogurts. At least you will be getting some beneficial bacteria from the yogurt, as it is one of the easiest forms of dairy to digest. As a substitute for milk, I use rice or soya milk on my breakfast cereal and use soya milk to make custard sweetened with maple syrup so we are not dependent on dairy foods, as evidenced by many cultures who do not eat it regularly such asChinaandJapan.
Fat around the Middle
It has been suggested that increased body fat is a much stronger predictor of breast cancer risk in women that just measuring the BMI (Body Mass Index). Scientists followed over 12,000 postmenopausal women for eight years and found that those who had gained more than 21kg since their menopause had a 75% higher risk of developing breast cancer compared to women with lower weight gain. Even when all the other risk factors such as smoking, alcohol consumption and HRT use had been taken into account, the body fat percentage was the most discriminating risk factor. (Lahmann PH et al, 2003, A prospective study of adiposity and postmenopausal breast cancer risk: the Malmo diet and cancer study, Int J Cancer, 103, 246-252)
We also know that where that fat goes on the body makes the risk of breast cancer even higher. Doctors at the Harvard School of Public Medicine in America studying 47,000 nurses over a ten-year-period found that those who had plump stomachs were 34 percent more likely to suffer from breast cancer than women with pear-shaped figures. When the researchers narrowed down the study to only post-menopausal women who had never taken HRT, the apple-shaped women were 88 percent more likely to get breast cancer. (Huang Z et al, 1999, Waist circumference, waist hip ratio and risk of breast cancer in the Nurses’ Health Study, Am J Epidemol, 150, 12, 1316-24)
Well, first of all stress effects the immune system, making it less efficient (see page X) and therefore more susceptible to attack from cancer cells. High cortisol levels reduce the number of cells called Natural Killer cells which normally work to help the immune system identify cancer cells as well as viruses. Cortisol also encourages new blood vessels to form in tumours (angiogenesis) which can stimulate their growth. Cancer cells function in a different way from healthy cells showing an increase in a process called ‘anaerobic glycolysis’. This means that they use glucose as their primary fuel. So if your blood glucose levels are high because you have insulin resistance and the insulin can’t do its job of moving the glucose out of the blood, there will inevitably be excess glucose on which the cancer cells can ‘feed’.
This effect of insulin was studied in a trial with over 49,000 postmenopausal women. The researcher found that women with a high carbohydrate and sugar intake had a significantly higher risk of breast cancer. Post menopausal women who ate foods with a high glycemic index (high sugar, white flour convenience foods) were 87% more likely to develop breast cancer than those on healthier low GI diets. The risk was particularly strong for women who had ever used HRT or who did no physical exercise. (Silver SA et al, 2005, Dietary carbohydrates and breast cancer risk: a prospective study of the roles of overall glycemic index and glycemic load, Int J Cancer, 114, 4, 653-8)
Insulin is classed as an anabolic steroid (a ‘grower or builder’ of cells) and one of the things it does is encourage cells to mutate. It also stops a process called apoptosis which is literally cell suicide. Healthy cells are normally programmed to die when they have fulfilled their function. If apoptosis is not happening then uncontrolled cell division can take place (just as it does in cancer and in the growth of cancerous tumours).
For further information see my book ‘Fat around the Middle’. READ MORE
Supplements for Breast Health
A multivitamin and minerals, vitamin C and Omega 3 fish oils are a good supplement programme. This will give you a good combination of nutrients including antioxidants and Omega 3 fish oils. The Omega 3 fish oils are important because they are known to protect against breast cancer and can help to inhibit tumour growth (Kaiser L et al, 1989, Nutrition and Cancer, 12, 61-8) and the combination of the DHA in the Omega 3 oils plus carotenoids (like beta carotene) in the multi can cut cancer risk in half (Nkondjock A, Ghadirian P, 2004, Am J Clin Nutr, 79, 857-64). Your multi should also contain good levels of folic acid as we know that if you are taking in more than 345mcg a day you have a 38% lower risk of breast cancer than those women who have intakes of less than 195mcg. (Shrubsole MJ et al, 2001, Cancer Research, 61, 7136-41).
To the above you should add in these extra nutrients:
Vitamin D – (300ius of D3) – this should be included in your multi but if you have a family history or a personal history of breast cancer then I would suggest that you have a blood test and add in extra vitamin D to correct a deficiency (if you have difficulty getting a vitamin D blood test then go to www.naturalhealthpractice.com)
Probiotics – These are important for your general health but they help to control oestrogen by binding it in the gut and helping your body excreting it efficiently, aim for one containing 22 billion organisms. (A good one I use in the clinic is called Advanced Probiotic Support see www.naturalhealthpractice.com).