Walnut consumption was found to reduce the size of prostate tumors and slow their growth in mice, and also had beneficial effects on genes related to the control of tumor growth and metabolism.
Although the experiments were carried out on mice, the researchers believe they are relevant to humans.
"This study shows that when mice with prostate tumors consume an amount of walnuts that could easily be eaten by a man, tumor growth is controlled," the study author said.
Researchers fed a diet with whole walnuts to mice that had been genetically programmed to get prostate cancer. After 18 weeks, they found that consuming the human equivalent of 2.4 ounces of walnuts per day resulted in significantly smaller, slower-growing prostate tumors compared to mice consuming the same diet with an equal amount of fat, but not from walnuts.
They also found that not only was prostate cancer growth reduced by 30 to 40 percent, but that the mice had lower blood levels of a particular protein, insulin-like growth factor (IGF-1), which has been strongly associated with prostate cancer. Additionally, they found beneficial effects on multiple genes related to controlling tumor growth and metabolism.
Walnuts are naturally high in a host of health-boosting nutrients. They contain the highest level of omega-3 fats compared to any other nut. They also provide a good source of B vitamins and minerals. They are an excellent source of Vitamin E, which contributes too their cancer-fighting properties. One of walnut's most valuable benefits is in fighting inflammation, which plays a role in many degenerative conditions of the brain and body.