What is Saw Palmetto?
Saw palmetto is an extract from the berries of Serenoa repens, a palm native to the southeastern United States. It is one of the most widely sold botanical ingredients in men's health supplements.
How it is used in supplements
It is marketed almost universally for prostate health and urinary symptoms associated with benign prostatic hyperplasia (BPH), and sometimes for hair loss.
What the research shows
The evidence is genuinely contested — and buyers deserve to know that. While some earlier and smaller studies suggested symptom improvements, large, well-designed trials, including a major NIH-funded study that tested up to triple the standard dose, found saw palmetto no better than placebo for BPH urinary symptoms. Systematic reviews reflect this mixed-to-negative picture. Evidence for hair loss is limited and preliminary.
Typical studied amounts
Studies have typically used 160 mg twice daily (320 mg/day) of a lipophilic extract standardized to fatty acids and sterols; trials testing higher doses did not find added benefit.
Safety and side effects
Generally well tolerated, with mild digestive upset the most reported effect. It does not appear to change PSA readings meaningfully, but men should still tell their doctor they take it before prostate testing.
Medication interactions
Theoretical interactions with hormonal therapies and blood thinners are described; robust interaction data is limited. Disclose use to your physician and pharmacist.
Who should be cautious
Urinary symptoms should be medically evaluated before reaching for supplements — they can indicate conditions that need diagnosis, including prostate cancer. Saw palmetto is not appropriate for women who are pregnant or breastfeeding.
References
- Saw Palmetto: Usefulness and Safety. National Center for Complementary and Integrative Health (NIH). https://www.nccih.nih.gov/health/saw-palmetto Accessed August 6, 2026.
Related ingredients & categories
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