Saw palmetto is the most popular prostate supplement worldwide, yet its clinical evidence is surprisingly mixed. The 2006 STEP trial (300+ men, funded by NIDDK) found saw palmetto 160mg 2x/day performed NO BETTER than placebo for benign prostatic hyperplasia (BPH) symptoms. However, European pharmaceutical studies using the Permixon® brand (hexanic lipidosterolic extract) consistently show benefit. Our research shows this discrepancy is likely due to extraction method: the hexanic extract preserves specific fatty acid ratios (lauric, myristic, oleic acids) that American CO₂ or ethanol extracts may not. At the molecular level, saw palmetto inhibits 5-alpha reductase (same target as finasteride) but at 1/5 the potency — explaining modest but real effects in select formulations.
Saw palmetto's lipidosterolic extract contains fatty acids (lauric, myristic, oleic, linoleic acids) and phytosterols (β-sitosterol) that: (1) inhibit 5-alpha reductase (types I and II), reducing conversion of testosterone to DHT (the androgen that drives prostate growth and hair loss); (2) inhibit DHT binding to the androgen receptor; (3) inhibit COX-2 and 5-LOX (anti-inflammatory — reduces prostatic inflammation); (4) inhibit growth factors (bFGF, EGF) that stimulate prostate cell proliferation. The hexanic extraction method specifically preserves the ratio of free fatty acids to fatty acid esters that appears critical for 5-AR inhibition — explaining the extract-dependent efficacy.
No critical interactions identified.
Reviewed by the Scan Dose Research Team and Clinical Advisory Board | Last updated:
Not medical advice. Based on published clinical research and systematic reviews.