A day never goes by without seeing numerous advertisements which usually are buried deep within the sports pages that advocate various fixes for the prostate. A Google search for prostate supplements just turned up over 2 million references! Clearly with so many claims, how can they all be true? Unfortunately they are not. Patients are often misled by claims made by the manufacturers of these nutritional supplements, however most evidence now does not support any of these substances in particular.
There was a lot of interest in the urology community regarding a fairly large study that was looking at various dietary supplements and the effect that they demonstrated on decreasing the risk of developing prostate cancer. In 2001, the National Cancer Institute (NCI) started the SELECT study. This study looked at the effects of selenium, and vitamin E on the development of prostate cancer. Initially hailed as a very promising study, after 5 years the trial was stopped as the early data did not demonstrate any evidence that the supplements were working.
Saw palmetto, a naturally occurring substance extracted from the fruit of the Sernoa repens, has been used in alternative medicine for benign prostatic hyperplasia. It blocks the conversion of testosterone to dihydrotestosterone (DHT*) the active substance that supports prostate growth. The drugs finasteride and dutasteride are styled after saw palmetto and both have been shown to effectively decrease the volume of the prostate, however there is a vast amount of conflicting data regarding the absolute benfits of the naturally occurring substance.
A healthy diet is advocated for the reduction of the risk of cancer. This includes a minimum of 5 vegetables daily especially broccoli and cauliflower, 3 whole grain products daily, and a reduction in the consumption of red meat. Increasing foods with omega-3 fatty acids such as salmon probably also decrease the risk of prostate cancer.
There is some evidence that flaxseed may in conjunction with a low-fat diet may decrease the risk of prostate cancer, however there is conflicting data regarding this. Pumpkin seeds have also been hailed as a magic potion for the prostate however, data is not conclusive.
Lycopene is an antioxidant that occurs in tomatoes, giving them their color. Prostate cancer has been shown to demonstrate a lower incidence in populations that have diets high in lycopene. Certain fruits such as watermelon, guava and papaya also contain lycopene. Although no specific anti-oxidant has been associated with decreasing the likelihood of prostate cancer, it is known that the use of these substances help deal with free radicals that may be associated with the development of cancer.
Lastly, “Buyer Beware” is good advice. The nutritional supplement industry is not very regulated. Unlike pharmaceutical companies, the manufacturers of dietary supplements are not required to demonstrate health benefits or safety prior to selling these products, although these rules are subject to change in 2010 (Dietary Supplement Safety Act of 2010). A study published in 2002 demonstrated that the actual content of some vitamin supplements do not contain the advertised amount and great variability is found.