Saw Palmetto
Also known as: Serenoa repens, Sabal serrulata, saw palmetto extract, SPE, LSESR
Effective Dosage
320 mg daily (most studied dose for urinary and hair outcomes)
What the Science Says
Saw palmetto is a berry extract from a small palm tree native to the southeastern United States. It is most studied for reducing urinary symptoms in men with benign prostatic hyperplasia (BPH) — such as frequent urination and weak flow — at a dose of 320 mg per day over 12 weeks. Emerging clinical trial data also show it can meaningfully increase hair count and density in both men and women with thinning hair, with results appearing within 90 days and continuing to improve through 6 months.
What It Doesn't Do
Not a replacement for prescription BPH medications or FDA-approved hair loss drugs like finasteride or minoxidil. Won't cure prostate enlargement or reverse severe hair loss. No evidence it works for women's hormonal conditions beyond hair thinning. Not proven to treat bacterial prostatitis. Don't expect overnight results — studies run 12–24 weeks.
Evidence-Based Benefits
Saw palmetto extract at 320 mg/day has shown significant improvements in lower urinary tract symptoms (LUTS) and quality of life in men with BPH, including improved IPSS scores and uroflowmetry parameters (PMIDs: 39675037, 39042923). For hair loss, proprietary saw palmetto extracts have demonstrated significant increases in terminal hair count, hair density, and reductions in hair shedding in both men and women with androgenetic alopecia or self-perceived thinning hair over 90–180 days (PMIDs: 41652806, 41319217, 38021422). In a retrospective cohort study, alpha-blocker plus saw palmetto combination therapy showed an 80% clinical response rate for chronic prostatitis/chronic pelvic pain syndrome, outperforming alpha-blocker monotherapy (PMID: 41414816).
Moderate EvidenceEffective at: 320 mg daily (most studied dose for BPH/LUTS and hair loss)
Source: auto-research
Absorption & Bioavailability
Unknown from provided studies. Lipid-based (fatty acid) extracts are the most studied form; standardized lipidosterolic extracts appear to be the active preparation used in trials.
Red Flags to Watch For
- Product quality varies widely — studies used USP-verified or proprietary standardized extracts; generic products may not match study formulations
- Hair growth studies were small (40 active, 20 placebo) and used a proprietary extract — results may not generalize to all saw palmetto products
- BPH urinary symptom study was single-arm with no placebo control, limiting confidence in those results
- Saw palmetto showed less than 50% CYP3A inhibition in vitro — low drug interaction risk, but consult a doctor if taking medications metabolized by CYP3A
- Not regulated as a drug — label claims and actual extract content may differ between brands
Products Containing Saw Palmetto
See how Saw Palmetto is used in these analyzed products:
Augustinus Bader The Hair Revitalizing Complex
Supplement
Hims Thick Fix System Total Hair Package
Supplement
Prostate Support
Supplement
NUTRAFOL Women Hair Growth Supplement
Supplement
Affiliatesupps
Supplement
Smartvita Men's Total Synergy Multivitamins
Supplement
Research Sources
- PubMed
- NIH DSLD
This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Last updated: 2026-04-06