Legumes are a type of plant that includes beans, lentils, lupins, peas, peanuts and soybeans. Several studies have shown that regular consumption of these foods can reduce the risk of prostate cancer. It showed that there was an inverse relationship between the amount of legumes consumed in the diet, and the rate of prostate cancer developed.
Soy has been touted to have a protective effect against prostate cancer, but studies have not been able to demonstrate that it is any more powerful in its protective effect than the other legumes.
My recommendation: Increase your dietary intake of legumes.