For men over the age of 50, prostate cancer is a legitimate health concern, affecting nearly 1 in 6 American men. Now, however, researchers believe that walnuts might decrease their risk for contracting the condition. In fact, walnut consumption was shown to slow the growth of tumors in animal models, as well as having some beneficial effects on the gene expression the underlies tumor growth and metabolism.

In the study, researchers placed mice with prostate tumors on diets of whole walnuts that was the equivalent of a human eating 2.4 ounces of per day. What scientists observed was that animals on the walnut diet had significantly smaller and slower progressing tumors than the ones who did not consume walnuts. In fact, tumor growth was decreased by as much as 30-40%. The walnut-free diet consisted of an equivalent amount of fat from alternative sources.

According the data, not only did the tumor growth slow down, but there was also lower detectable levels of a protein (insulin-like growth factor, or IGF-1) that has been strongly linked to prostate cancer. Furthermore, using state-of-the-art technology, the researchers were able to measure the gene expression of the cancer cells and found that walnuts had some beneficial effect even on that level, as well.

The findings add to the growing list of healthful qualities of walnuts. The reason for this is because in addition to being a good source of protein and antioxidants, walnuts are rich in the omega-3 fatty acids, and one quarter of a cup of walnuts provides as much as 90% of the daily value of these fats.

Omega-3s are special fats that our bodies cannot produce and must be obtained through the foods we eat. Good sources include flaxseeds, fish, and walnuts. Omega-3s are believed to confer a whole host of health benefits, including protecting our hearts, supporting mental health, reducing inflammation, strengthening the immune system, maintaining healthy skin, and reducing the risk for certain cancers, including, perhaps, prostate cancer.

Prostate cancer affects the prostate gland, which is located just below the bladder, and is responsible for the production of the fluid in semen. It is in fact one form of cancer where environmental factors can play an important role in its development, especially diet. Prostate cancer is the third leading cause of cancer death in men and generally occurs after the age of 40. Treatment depends on the stage of the condition, and can include surgery, radiation, and chemotherapy.

If you are over the age of 40 and have questions or concern about prostate cancer, speak with your physician. For more information, visit the websites for the Prostate Cancer Foundation and the American Cancer Society.