September is National Prostate Cancer Awareness Month. Other than skin cancer, prostate cancer is the most common cancer among men. According to the American Cancer Society, 1 in 7 American men will develop prostate cancer in their lifetime.
Although there is no “miracle diet” for cancer, a few specific nutrients have shown promise. Consuming a plant-based diet has shown the greatest protection for most cancers, including prostate cancer. The National Cancer Institute recommends aiming for five to nine servings of fruits and vegetables daily for cancer prevention. Cruciferous vegetables in particular contain glucosinolates, which are powerful plant compounds that protect cells from oxidative damage. Cruciferous veggies such as broccoli, cauliflower, Brussels sprouts, kale, and collards offer the greatest nutrient absorption if consumed raw or lightly cooked. Lycopene, a pigment of the carotenoid family, is found in tomatoes, guava, grapefruit, and watermelon and is responsible for the red and pink hue in these fruits. Lycopene is most concentrated in processed tomato products including tomato juice, tomato paste, and spaghetti sauce. Research has shown that men who consume tomato products containing lycopene on a daily basis have lower incidence of prostate cancer.
Green tea also shows promise on the cancer prevention front. Green tea contains antioxidants called flavonoids that help inhibit cancer cell growth. The greatest benefit is seen in those who consume several cups per day.
Soy and flaxseeds contain lignans, which are a weak form of plant estrogen. It was originally thought that these plant estrogens could counteract hormone driven cancers like prostate cancer; however, the verdict is still out to determine if this provides a true benefit. Nonetheless, soy is an excellent lean protein source and flaxseeds provide protein, fiber, and omega-3 fatty acids, all of which are important in a healthy eating plan. Be sure to opt for whole soy foods over processed soy protein powders and isolates.
Some nutrients may have a negative impact on prostate health. A large body of research indicates that prostate cancer risk increases with high calcium intake. As most calcium intake is derived from dairy foods in the United States, many studies have focused on dairy intake and found increased risk with greater than 3-5 servings of dairy per day. The RDA for calcium is 1,000-1,200 mg/day for adults, or about 3 servings of dairy (1 serving equals 1 cup milk or yogurt, or 1 ounce of cheese). It is best to consume dairy in moderation and not to exceed the RDA for calcium from food or supplements.
Furthermore, some food preparation methods, such as grilling or charring, release carcinogens which can damage cellular DNA when consumed. Continuously rotating the meat or cutting off burned portions limits exposure to these carcinogens.
For prostate cancer survivors, key recommendations include maintaining a healthy weight, limiting alcohol consumption (no more than two drinks per day), and focusing on a plant-based diet with limited amounts of red meats and refined sugars. Simple daily lifestyle changes like drinking plenty of water, getting regular exercise, and taking a few minutes each day to relax and de-stress are also keys to cancer prevention and survivorship.
Natalie Colla, RDN, LDN, is a dietitian and diabetes program coordinator with Panhandle Health District.