Saw Palmetto Shampoo: What the Studies Actually Tested
Saw palmetto is one of the most common botanicals on thinning-hair shampoo labels. Before you pay extra for it, it helps to know what the research tested, because it was not shampoo.
What saw palmetto is
Saw palmetto is an extract from the berries of a small palm that grows in the southeastern United States. It is best known as a supplement for prostate health, and hair-care brands use it because of its link to DHT, the hormone most associated with pattern hair loss.
The topical research
A 2020 systematic review by Evron and colleagues in Skin Appendage Disorders collected the human studies on saw palmetto and hair loss. Two looked at products applied to the scalp.
A 50-week controlled trial. Morganti and colleagues followed 60 men and women using a topical saw palmetto product, compared with a vehicle. Hair counts rose more in the treated groups than with the vehicle alone, and no side effects were reported.
A 24-week study in 50 men. Wessagowit and colleagues had men apply a saw palmetto lotion to the whole scalp every day, plus a concentrated serum on thinning areas for the first four weeks. Terminal hair counts went up over the six months. The review pointed out an important weakness: there was no comparison group, so we can't tell how much of the change came from the product.
Why it matters that these weren't shampoos
Both studies used leave-on products. They stayed on the scalp for hours. A shampoo stays on for a few minutes and then goes down the drain.
That doesn't make saw palmetto in a shampoo useless, but it does change what you should expect. Think of it as a supporting ingredient in a good scalp routine, not the main reason to buy a bottle. Leaving the lather on for three to five minutes gives it, and everything else in the formula, the best chance.
Which shampoos contain it
Three shampoos in our comparison list saw palmetto:
- Regenepure DR pairs it with ketoconazole, caffeine, emu oil and niacin in a base with no sulfates. It is the only one that combines saw palmetto with ketoconazole, and our top pick.
- Hims Thick Fix pairs it with niacinamide in a small 6.4 oz bottle.
- Pura D'or Gold Label pairs it with biotin, argan oil and nettle in a large bottle.
If saw palmetto is the reason you are shopping, the bigger question is what it comes with. A shampoo that also brings ketoconazole covers the ingredient dermatologists name most often.
Read more about saw palmetto and ketoconazole.
Sources
- Evron E, Juhasz M, Babadjouni A, Mesinkovska NA. Natural hair supplement: friend or foe? Saw palmetto, a systematic review in alopecia. Skin Appendage Disorders, 2020.