Saw Palmetto
Saw palmetto: what NIH says (probably not helpful for enlarged prostate symptoms), what is known about hair loss, and safety.
Content last updated . This page has not been medically reviewed.
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Overview
Saw palmetto is a small tree native to the West Indies and the southeast coast of North America. Its berries are used. It is promoted as a supplement for urinary symptoms of an enlarged prostate (benign prostatic hyperplasia, BPH), male-pattern baldness and chronic prostatitis. [1]Names and parts
Serenoa repens (synonyms Serenoa serrulata, Sabal serrulata). [1][2] Berry extract is used.What the research shows (NIH summary)
NIH says it knows enough to conclude saw palmetto is probably not helpful for BPH urinary symptoms. [1]| Use | What NIH says | Strength of evidence |
|---|---|---|
| Urinary symptoms from BPH | A 2023 review of 27 studies found little or no benefit when taken alone. Two NIH-funded trials, one at up to three times the usual dose, did not improve symptoms. Hexane-extracted and other products did not differ. [1] | Negative |
| Combination herb products including saw palmetto | Definite conclusions could not be reached. [1] | Unclear |
| Chronic prostatitis / pelvic pain | A 2022 review of five studies found no significant benefit. [1] | Negative |
| Male-pattern hair loss | A few small studies; too limited for conclusions. [1] | Insufficient |
Safety
- Well tolerated and used safely in studies for up to 3 years. Adverse effects are mild and infrequent: digestive symptoms, dizziness and headache. [1]
- It does not appear to affect PSA test readings. [1] Tell your clinician if you take it, since urinary symptoms can have serious causes that need a proper diagnosis.
- It may be unsafe in pregnancy or breastfeeding. [1]
Frequently asked questions
Does saw palmetto shrink the prostate?
NIH says it probably does not help urinary symptoms of BPH when taken alone. [1]
Does saw palmetto regrow hair?
NIH says the evidence is too limited to allow conclusions. [1]
References
- National Center for Complementary and Integrative Health (NIH). Saw Palmetto: Usefulness and Safety. Page last updated April 2025.
- GBIF Secretariat. GBIF Backbone Taxonomy. Names checked 2026-10-22 through the GBIF species match service.
Education, not medical advice. This page is for general information. It does not diagnose or treat any condition and is not a substitute for care from a qualified health professional. Natural does not automatically mean safe. Ask a clinician or pharmacist before changing your care, especially if you take medication, are pregnant or breastfeeding, or have a health condition.