Saw Palmetto Supplement Use and Prostate Cancer Risk

Abstract

Saw palmetto is an herb used to treat the symptoms of benign prostatic hyperplasia. In vitro studies have found that saw palmetto inhibits growth of prostatic cancer cells and may induce apoptosis. To evaluate whether saw palmetto supplements are associated with a reduced risk of prostate cancer, we conducted a prospective cohort study of 35,171 men aged 50-76 yr in western Washington state. Subjects completed questionnaires between 2000 and 2002 on frequency of use of saw palmetto supplements and saw palmetto-containing multivitamins over the previous 10 yr in addition to other information on supplement intake, medical history, and demographics. Men were followed through December 2003 (mean of 2.3 yr of follow-up) via the western Washington Surveillance, Epidemiology, and End Results cancer registry, during which time 580 developed prostate cancer. Ten percent of the cohort used saw palmetto at least once per week for a year in the 10 yr before baseline. No association was found between this level of use of saw palmetto and risk of prostate cancer development [hazard ratio (HR) = 0.95; 95% confidence interval = 0.74-1.23] or with increasing frequency or duration of use. In this free-living population, use of commercial saw palmetto, which varies widely in dose and constituent ratios, was not associated with prostate cancer risk.

Specialty Supplements and Prostate Cancer Risk in the VITamins And Lifestyle (VITAL) Cohort

“…We previously reported no association between use of saw palmetto, typically taken for BPH, and prostate cancer risk in this cohort (HR 0.95, 95% CI: 0.74–1.23) (25); after an additional 4 years of follow-up, we continue to observe no association. Biggs et al (60), reported results of a secondary analysis of the Ginkgo Evaluation of Memory (GEM) randomized trial.…”

“…However, there are almost no human studies of these supplements and prostate cancer risk. In a previous analysis, we found no association of regular saw palmetto use with prostate cancer risk in the VITamins And Lifestyle (VITAL) cohort after 2 years of follow-up (25). …”

Complementary and alternative medicine: Herbals and supplements: A review for the primary care physician

“…Rhabdomyolysis, likely induced by saw palmetto, has been reported [52][53]. While the benefits of saw palmetto for manifestations of BPH are yet to be confirmed, there has been no demonstrable association between saw palmetto use and prostate cancer risk [54]. Drug interactions can occur, including an increased likelihood for bleeding.…”

New Natural Pigment Fraction Isolated from Saw Palmetto: Potential for Adjuvant Therapy of Hepatocellular Carcinoma

“…In vivo study using transgenic prostate adenocarcinoma murine model also postulated that the administration of lipidosterolic extract (300 mg/kg/day) may prevent tumor occurrence [12]. However, epidemiology [13] and randomized trials [14] demonstrated that there is no association of prostate cancer risk between the intervention and placebo group. Although the result discrepancy between the studies may not conclude the effect of Saw Palmetto lipidosterolic extract in prostate cancer prevention, we could not preclude the potential anti-tumor effect of Saw Palmetto in other tumor models.…”