Saw Palmetto Hysteria – What SCIENCE Says

Last week a popular YouTube personality created a firestorm by introducing her own brand of beauty supplements instead of the glamourous line of cosmetics, skincare or makeup brushes her audience was clearly hoping for (and expecting).

The backlash was swift and vicious. Many comments were pointed and direct in conveying disappointment. But many people attacked more indirectly by taking aim not at the blogger but at the ingredients in the supplement. One component in particular drew their fire – the herbal product known as saw palmetto.

So What, Exactly, Is Saw Palmetto?

Botanically, saw palmetto is known as Serenoa repens and is the only existing species in the Serenoa genus. It is found along the forested Gulf coast, throughout Florida and along the Southeast coastline.

Seminole people reportedly ate saw palmetto berries and trunks as food while both they and people in the Choctaw Nation used the plants to make baskets and other goods.

Archeological evidence suggests that the plant and goods made from it were widely traded. There is considerably less evidence that saw palmetto was extensively employed by Native Americans as a medicinal plant.

Saw Palmetto As An Herbal Medicine

Today, saw palmetto is perhaps best known as a potential herbal remedy for enlarged prostate and extracts of saw palmetto berries are available pretty much worldwide for just that purpose. In 1989 Germany’s Commission E, which is an advisory board tasked with scientifically investigating folk medicines, approved doses of between 1 and 2 grams of saw palmetto berry (or 320 mg of the berry extract) for men experiencing urination difficulties caused by stage 1 or stage 2 benign prostatic hyperplasia, which is commonly known as enlarged prostate.

Here in the U.S., saw palmetto makes up a sizable chunk of an estimated $6.4 billion market in “natural” prostate remedies.

Recent research, though, has cast doubt on the effectiveness of saw palmetto. A 2016 review-study, for example, found it no better than placebo. That holds true even at higher-than-normal doses.

Does Saw Palmetto Really “Cancel” Out Birth Control Pills?

The vast majority of the criticism I see about this particular supplement involves the claim that the saw palmetto component could somehow render oral contraceptives ineffective. Many people making this claim point to this bit of the WebMD profile on the herb:

Does Tati Westbrook's Halo Beauty put women at risk for pregnancy with its saw palmetto ingredient?

Screenshot of WebMD profile on saw palmetto, with birth control caution visible, taken by Lisa Barger.

The author of that article appears to be not a medical doctor or scientific researcher but someone hired to write what are called user-generated articles for WebMD. The author also appears to be pulling the information about a possible interaction with birth control pills from the non-professional version of Natural Medicines Comprehensive Database.

Here is where things get complicated. We know, for example, that saw palmetto berries demonstrate anti-androgenic and anti-estrogenic activity in the human body. However no authoritative body–the National Institutes of Health, the World Health Organization, the U. S. Food and Drug Administration, the EU’s Committee on Herbal Medicinal Products, etc.– I could find lists any warnings about taking typical doses of saw palmetto with birth control pills. (The herb is not, of course, recommended for children, pregnant women or nursing mothers.)

I also searched through the major medical databases and could find no evidence to support the saw-palmetto-cancels-birth-control claim. No doctor, as far as I can tell, has ever reported a patient becoming pregnant as a result of an interaction between her oral contraceptives and a saw palmetto supplement.

Closing Thoughts

I watched the blogger’s brand teaser video, the product’s launch video and the blogger’s follow-up video in which she attempts to mollify her critics. It’s obvious she gave them a lot of fodder to work with. (An example – her repeated use of the word “vitamin” to describe her supplement was especially grating to me.)

And speaking as someone who has covered the U. S. Food and Drug Administration, or FDA, for more than a decade, I saw a lot of things about the way the product is being marketed that I suspect will definitely draw the agency’s ire in the future.

But does that make the supplement unsafe for most people? Not by a long shot. Right now, the actual science does not support the claim that the supplement or any ingredient in it could “cancel out” oral contraceptives.


Additional Sources:

Moreman, D. (1998). Native American Ethnobotany. Timber Press.

Whitford, A. (1941). Textile Fibers Used in Eastern aboriginal North America. Anthropological Papers of the American Museum of Natural History.

Keehn, A., et al. (2016). Phytotherapy for Benign Prostatic Hyperplasia. Current Urology Reports.

German Commission E. (1989). Saw Palmetto Berry (Sabal Fructus). List of German Commission E Monographs (Phytotherapy).