Saw palmetto and hair loss: the evidence so far

Saw palmetto is an extract from the fruit of a small palm. It is one of the most common ingredients in "natural" hair supplements, often promoted as a gentler alternative to prescription medicines for pattern hair loss. How strong is the evidence?

Why saw palmetto is linked with hair

Pattern hair loss is driven partly by hormones called androgens. Saw palmetto is described as a botanical extract with antiandrogenic properties, which is why it has gained commercial popularity for hair ¹. A 2025 review of herbal remedies notes that some herbs studied for hair loss are thought to act through 5-alpha-reductase inhibition, the same pathway targeted by finasteride, among other mechanisms ².

Having a plausible mechanism is a starting point, not proof that something works in people.

The main systematic review

A 2020 systematic review searched medical databases for studies of saw palmetto in hair loss ¹. It found:

• 5 randomised clinical trials and 2 prospective cohort studies using topical or oral products containing saw palmetto, at doses of 100 to 320 mg ¹.
• Participants had pattern hair loss or telogen effluvium, a type of temporary shedding ¹.
• Across these studies, results included a 60% improvement in overall hair quality, a 27% improvement in total hair count, increased hair density in 83.3% of patients and stabilised hair loss in 52% ¹.
• Saw palmetto was well tolerated and was not associated with serious side effects in these studies ¹.

These numbers can look impressive, but they come from different small studies using different products, so they cannot be added up into a single reliable effect.

The important caveats

The review authors were cautious. They wrote that robust, high-quality data are lacking, and that larger trials focusing on the sole contribution of saw palmetto are needed to confirm whether it works and to understand long-term side effects ¹.

That last point matters. Many products studied were supplements containing saw palmetto alongside other ingredients ¹. When a product contains several ingredients, it is hard to know which one, if any, made the difference.

A broader 2025 review of herbal remedies, including saw palmetto, reached a similar view: they show promise, but many studies have small sample sizes, short treatment periods and little long-term follow-up, and better randomised trials are needed ².

What a 2025 network meta-analysis added

A network meta-analysis of 19 randomised trials of dietary supplements in 1,658 people with pattern hair loss compared many supplements at once ³. A saw palmetto extract was among the supplements that scored higher than placebo or conventional treatment in blinded doctor assessments, but it was not among those shown to improve measured hair density ³. The authors found supplements well tolerated overall and called for larger, high-quality trials ³.

How it compares with finasteride

Finasteride has been studied in many good-quality randomised trials, and a 2017 meta-analysis found 1 mg finasteride better than placebo for men with pattern hair loss ⁴. The NHS lists finasteride and minoxidil as the main treatments for male pattern baldness, while noting no treatment is 100% effective ⁵.

Saw palmetto does not have evidence of that size or quality. It should not be treated as an equal substitute. See using minoxidil and finasteride together and an overview of pattern baldness treatment.

Safety and practical points

• Talk to a pharmacist or doctor first if you take regular medicines, have a hormone-related condition, are pregnant, breastfeeding or planning pregnancy. Because saw palmetto is described as antiandrogenic, it is sensible to check before use. See questions to ask your pharmacist.
• Check the label. Look for the amount of saw palmetto per dose and a product registration number for supplements sold in Malaysia.
• Avoid stacking. Taking several hair supplements together makes it harder to judge any effect and raises the risk of side effects from other ingredients.
• Set a trial period. Hair changes slowly, so take photos at the start and after several months.
• Do not stop a proven treatment to switch to saw palmetto without advice.

The bottom line

Saw palmetto has a plausible mechanism and some small, positive studies, and it appears well tolerated. But the reviewers themselves say high-quality evidence is missing. If you choose to try it, see it as an experiment alongside, not instead of, treatments with stronger evidence. For other popular ingredients, see tocotrienols, caffeine shampoo and he shou wu.

Frequently asked questions

Does saw palmetto work for hair loss?

Small studies report positive results, but a systematic review found robust, high-quality data are lacking ¹.

Is saw palmetto as good as finasteride?

There is no good evidence that it is. Finasteride has been shown better than placebo in good-quality trials ⁴; saw palmetto has not been tested to that standard ¹.

Is saw palmetto safe?

In the studies reviewed it was well tolerated without serious side effects, but long-term effects need more research ¹.

What dose was used in studies?

Studies used topical and oral products containing 100 to 320 mg of saw palmetto ¹.

Educational content. Not medical advice.