Diet and Prostate Cancer
Frequently people ask if there is anything in our diets that may reduce the risk of getting prostate cancer or improve the prospects of patients who have, unfortunately, been diagnosed with prostate cancer. Certainly in men with a family history of prostate cancer or who wish to try to avoid prostate cancer, there is now fairly compelling evidence to suggest that a combination of selenium and vitamin E may well be effective and seems unlikely to cause significant side-effects.
Selenium is a trace nutrient which may prevent damage by carcinogens and its effect was discovered during a trial of selenium to try to reduce the recurrence of skin cancer. Those men taking selenium at a dose of 200 mcgs daily had a 63-74% reduction in the risk of prostate cancer. In addition, there is also some indirect evidence for the effects of vitamin E in low-dose and the maximum recommended dose would be 150 iu per day. It would also appear that drinking 4-7 glasses of red wine per week may also help reduce the risk of prostate cancer.
For those teetotallers amongst you or those who wish to try and find additional protection, recent interest has been shown in the effects of green tea. We know that Asian men from Korea , China and Japan have a significantly lower prevalence of aggressive prostate cancer and it was felt that this may be due to their dietary intake of soya and tea. Green tea contains polyphenols which, in animal models, have been shown to markedly reduce the development of metastases in prostate cancer. This required the drinking of the equivalent of six cups of green tea per day! It would certainly be worth considering changing from conventional tea to green tea, which is now available in most supermarkets. In patients who have a diagnosis of prostate cancer and in whom the cancer may or may not have spread, it would appear that green tea offers no significant benefit.
Certainly reducing the intake of saturated animal fats found in red meats including beef, lamb, pork and dairy products may well have an effect on survival. Licopenes are powerful anti-oxidants which give tomatoes their red colour; cooking tomatoes in olive oil increases the amount of licopene available for absorption by the gut. Licopenes are also found in a wide range of coloured fruits and vegetables including strawberries, carrots, etc. Tomato sauce and tomato puree have the highest levels of licopenes and their intake should be encouraged. In addition, licopenes can be obtained from most health food shops.
Soya bean products, (soya milk as a substitute for cow milk and tofu as a substitute for meat) are good sources of omega-3 fatty acids and contain isoflavones which may help reduce prostate cancer rates and its progression. The recommended daily intake would appear to be approximately 30g of soya produce per day.
There is certainly good evidence that increasing dietary intake of fruits and vegetables is beneficial and the most effective vegetables are probably the cabbage family, (cruciferous). This includes broccoli, Brussels sprouts, watercress, Swiss chard, beet greens, etc. Broccoli appears to have very beneficial effects in many aspects.
Finally there is also evidence that increasing the intake of omega-3 compounds may be protective and may be beneficial in patients with prostate cancer. These compounds are found in oily fish, soya beans and specially-fed chickens can produce eggs high in omega-3. One way of increasing intake is to eat oily fish such as mackerel, salmon and tuna.
In general, eating a well-balanced diet and taking regular exercise will help the feeling of well-being and promote health.