Ask the Nutritionist
Q: I have significant and early enlargement of one of the lobes of my prostate (I am 52 years old) which, if it continues to worsen, may lead to prostate surgery within two years. I am already on finasteride, but would prefer to supplement my diet with macronutrients and vitamins/supplements to slow the process. I have heard about supplementing with selenium, zinc and boron, amongst others, as a way to retard prostate enlargement. What can you recommend?
A: While there aren't any surefire ways to slow benign prostate enlargement through the diet, there are some tips to promote general prostate health.
Current research supports a diet low in read meat and saturated fat and high in vegetables, fruits, and whole grains.
Since you're on finasteride, it is advised that you avoid eating grapefruit. However, you can load up on other lycopene-rich foods like tomatoes, watermelon, and apricots, which have antioxidants that may help protect your prostate's DNA from free-radical damage.
As for vitamin and mineral supplements, a review of nine randomized, controlled trials published in August 2010 found that antioxidant vitamins and selenium supplements did not reduce the risk for developing or dying from prostate cancer.
Another important study on this subject, SELECT, a 2009 randomized, controlled trial that followed 35,000 men for five years, also did not find selenium supplements beneficial in preventing the occurrence of prostate cancer.
However, SELECT only used one form of selenium. More research needs to be done to determine what form and dose of selenium supplement, if any, is beneficial.
Taking selenium supplements along with other vitamins may even increase risk: the SELECT trial was stopped early when researchers saw a trend toward increasing risk of prostate cancer and diabetes in the group of men taking vitamin E and selenium supplements.
Previous, smaller studies found a relationship between dietary selenium and risk-reduction.
If you'd like to add selenium through your diet, try adding a quarter cup of sunflower seeds to your sandwich or salad. Brazil nuts and fish like tuna, salmon, and cod are also high in selenium.
The research on zinc is mixed. Some studies show no effect while others, like the VITAL trial, found that men who had prostate cancer and took zinc supplements had a lower risk of developing advanced stage prostate cancer than men who were not.
Keep in mind that this study did not look at whether taking zinc supplements lowers the risk of getting prostate cancer in the first place. Fortified breakfast cereal, cashews, chicken, and oysters are good sources of dietary zinc.
Boron did not reduce the risk of prostate cancer, whether it was taken from the diet alone or with supplements, according to a report on the men who participated in the 2009 VITAL trial.
The best strategy to reduce the risk of developing prostate cancer is to follow the reliable adage: maintain a healthy weight and eat a balanced diet high in whole grains, full of vegetables and fruits (especially those with lycopene), and low in fat.
For people looking to reduce their risk of developing symptomatic benign prostate enlargement, a 2007 study found that while high-fat diets and diets high in red meat increased the risk of this condition, diets high in protein and vegetables lowered risk.
Researchers in this study also found that people getting a lot of zinc from their diet and taking vitamin D supplements had a reduced risk. The results of this one study should be taken in context: as of now, there are no modifiable risk factors to prevent the condition.
However, an overall healthy diet rich in plant-based foods is recommended for good prostate health.
Please always consult your doctor before taking supplements or herbal remedies.