J. Curtis Nickel, MD, FRCSC

J. Curtis Nickel, MD, FRCSC, the Canada Research Chair in Urologic Pain and Inflammation and Professor of Urology at Queen’s University in Kingston, Ontario, discusses research on the herbal medicine saw palmetto and its efficacy as an alternative therapy for benign prostatic hyperplasia (BPH)/lower urinary tract symptoms (LUTS), prostatitis, and prostate cancer. He relates the history of saw palmetto, explaining that it has been used to treat urinary problems for centuries, but fell out of widespread use in North America at the start of the the modern pharmaceutical era in the 1920s, though physicians in Europe continued prescribing it. Dr. Nickel notes that there are two primary forms of saw palmetto products in North America: saw palmetto extract, which is high in fatty acids; and saw palmetto ground berry powder, which is low in fatty acids. Dr. Nickel emphasizes that the presence of fatty acids is important since prostate cells preferentially take up fatty acids and sterols. He highlights the difference between the North American guidelines, which state that “the available data do not suggest that saw palmetto has a clinically meaningful effect on LUTS secondary to BPH,” and the European guidelines which recommend using saw palmetto on the “basis of its long-standing use.” Dr. Nickel then considers the evidence, explaining that a literature review of 1575 research publications on saw palmetto and LUTS indicates saw palmetto extracts are safe, improve symptoms, and improve quality of life. He then looks at the potential role of saw palmetto in treating prostatitis, a prevalent condition in North American men. Dr. Nickel explains that until recently, researchers could not find evidence from randomized placebo-controlled trials to substantiate findings that the hexanic extract of saw palmetto reduces prostate inflammation. However, he notes, a recent trial suggests saw palmetto extract is effective, safe, and clinically superior to placebo for the treatment of chronic prostatitis/chronic pelvic pain syndrome. Dr. Nickel then turns to the question of whether or not saw palmetto could have a role in managing prostate cancer. He explains that saw palmetto seems like it could have value in preventing or managing prostate cancer since it antagonizes 5ɑ-reductase to reduce DHT production, inhibits DHT binding to androgen receptors, inhibits the expression of Cox-2, inhibits prostate cell growth, etc. However, studies have not found any association between use of saw palmetto and risk of prostate cancer development, nor any correlation with increasing frequency or duration of use. Dr. Nickel concludes that saw palmetto extract is a valuable alternative therapy for men with mild to moderate LUTS/BPH, that it is potentially a useful alternative therapy for prostatitis, and that it does not play a role in prostate cancer prevention or treatment in 2022.