Saw Palmetto for Prostate and Hair Loss: Dosage and Evidence

Saw palmetto's lipidic extract weakly inhibits the type-2 isoform of 5-alpha-reductase, the enzyme that converts testosterone into dihydrotestosterone (DHT), the hormone driving both BPH and androgenetic alopecia. It also reduces prostate inflammation by modulating COX-2 and 5-lipoxygenase pathways and may have anti-androgen receptor binding effects.

• BPH symptoms: 20 to 30% improvement in urinary flow and nighttime urgency in men with mild-to-moderate BPH.
• Androgenetic alopecia: emerging evidence for slowing hair-loss progression in men.
• Sexual side effects: much lower rate than finasteride, saw palmetto rarely causes erectile or libido changes.
• Inflammatory markers in prostate tissue: histological improvements in trial biopsies.

Cochrane reviews historically split on saw palmetto's BPH efficacy because early trials used non-standardised preparations. Trials using the standardised lipidic extract (Permixon, Prostagutt) show consistent modest benefit (Boyle 2004, Carraro 1996). More recent meta-analyses focusing on standardised preparations show statistically significant symptom improvement vs placebo.

320 mg/day of the standardised lipidic extract (typically 85 to 95% fatty acids and sterols). This is the dose used in essentially all positive trials. Powdered berry preparations require 1 to 2 g/day for similar effect and are less consistent. Take with a fatty meal for absorption.

Mild GI upset on an empty stomach. Headache, dizziness in 1 to 3% of users. Rare: liver enzyme elevations (case reports). Sexual side effects (erectile dysfunction, libido reduction) occur in <2%, far less than finasteride's 5 to 8%.

Antiplatelet/anticoagulant medications, saw palmetto has mild antiplatelet activity. Hormone-sensitive medications, discuss with prescriber. Notably interferes with PSA testing, your urologist needs to know you're taking it before interpreting PSA results.