Prostate cancer is the second most common cancer in men worldwide, and is more common in developed countries. I googled it to write about foods that are helpful to prostate cancer, and I was so embarrassed that a lot of wierd health supplements came out. Maybe, prostate cancer is one of good targets to sell health supplements, so I felt a bit bitter.
Today, I will introduce foods that have scientific evidences to decrease the risk of prostate cancer.
There have been many stuides investigating soya and soya products. Meta-analysis of case-control data showed a clear dose-response relationship between legume intake and prostate cancer. By collecting and analyzing 14 related studies, those who consume soya had a 26% lower risk of prostate cancer than those who did not.
Soya foods contain various compounds that may have anti-cancer effects. Some of them involve in the metabolism of estrogen, can act as phytoestrogens, and can prevent the testosterone-induced growth of prostate. If you are worried about prostate cancer, you should now drink soy milk instead of milk.
Selenium is known as a powerful anti-oxidant. Selenium has also been studied extensively for prostate cancer. In particular, the risk of advanced prostate cancer is further reduced with increased intake of selenium. Blood concentrations of selenium were also associated with prostate cancer, and people with a serum selenium concentration higher than 100ng had a 20% lower risk of prostate cancer.
Selenium is related to seleno-protein production which is known to be important for anti-inflammatory and anti-oxidant properties. the seleno-protein is also involved in testosteron production and can play an important role in regulating abnormal prostate growth.
The recommended daily intake of selenium is very low, about 50-200 μg. Selenium can be well absorbed by various foods, so you can take enough amount through normal diet. Lists of foods contain selenium: nuts, fish, animal liver, egg, chicken, spinach, etc.
I have already mentioned the relationship between lycopene and prostate cancer in the 'Tomato and Cancer' section. Lycopene and lycopene-containing foods such as tomato reduce the risk of prostate cancer. Processed tomato including tomato sauce can increase the bioavilability of lycopene, which can be even more beneficial for prostate cancer. A study of serum lycopene concentrations also reported that the risk of prostate cancer was reduced with high concentration of lycopene.
Lycopene is one of the most potent antioxidants in carotenoids. Lycopene inhibits cell proliferation, reduces LDL cholesterol, increases immune function, and also has anti-inflammatory properties.
4. Vitamine E (Alpha-tocoperol)
Vitamine E is present in 8 different forms and all belong to anti-oxidants. Among them, alpha-tocopherol is the most biologically active substance, and is the most widely used vitamin E supplements on the market. In a study conducted on male smokers with 50 mg of alpha-tocopherol, the risk of prostate cancer was reduced by 34%.
Vegetable oils, seeds and nuts are rich in vitamin E. For example, sunflower seeds and oil, almond oil, hazelnut oil, abalone, pine nuts, peanuts, and avocados. A study of the intake of vitamin E-containing foods also showed a reduction in the risk of prostate cancer. In addition, a study investigating blood levels of alpha-tocopherol and gamma-tocopherol, wich are types of vitamine E, showed the dose-response relathionship with prostate cancer.
There are different types of food that can be helpful to differnt kinds of cancers. I think it is not a good way to have only 'healthy food' to prevent a specific disease. I advise eating various nutrients with knowing that some compounds can be good or bad. Don't experiment your body with specific food.
Yan L, Spitznagel EL. Soy consumption and prostate cancer risk in men: a revist of a meta-analysis. The american journal of clinical nutrition. 2009, 89(4):1155-1163.
World Cancer Research Fund & American Institue for Cancer Research. Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective. 2007.