Dear John,
I am worried about developing prostate cancer. I am an older man, and understand that eating a whole foods plant-based diet and avoiding dairy products will lower my risk, but is there anything else I can do to avoid this disease?
Harvey
Dear Harvey,
Yes, there is. A study published in the Journal of Urology in 2001 found that men with high blood levels of the mineral selenium had a four- to five-fold decrease in the risk of prostate cancer. “This study showed that there was a direct connection between selenium and prostate cancer,” said Stanford’s Dr. James Brooks, lead author of the study. “Older men with higher levels of selenium were at lower risk, while, conversely, individuals with the lowest range of plasma selenium represent a population at risk for the development of prostate cancer.”
The study’s authors suggest taking selenium supplements to ward off this most common form of cancer in men. If you are going to take supplements, though, don’t fall into the trap of believing that if some is good, then more is automatically better. Too much selenium can be dangerous. More than 400 mcg a day is probably not helpful. 2,500 mcg per day is almost certainly toxic to most people. 200 – 250 mcg a day is quite enough.
If you derive your selenium from foods rather than supplements, there is little chance of overdosing. Brazil nuts are the best food source of selenium. Garlic, whole grains, sunflower seeds, broccoli sprouts, and other nuts and seeds are all good sources of selenium, if they are grown on selenium-rich soil.
Tables that show how much selenium can be found in specific quantities of individual foods are of little use, because selenium levels in foods vary depending on the amount of selenium available in the soil. Selenium levels in most U.S. and Canadian soils are generally adequate, but U.K. and European soils are often deficient. If I were living in these parts of the world, I would definitely either take selenium supplements, or be sure I ate two or three Brazil nuts every day.
May your years be long and healthy,
John