Numerous studies have shown saw palmetto to reduce levels of dihydrotestosterone – the main hormone thought to be responsible for hair loss. As an extract from Serenoa repens – a fruit – it’s a natural hair loss treatment that has a similar mechanism of action to prescription hair loss drugs like Propecia. So if you’re suffering from hair loss but experience side effects from the prescription solutions, this herbal medicine may be a viable and effective alternative. But does it actually work for hair loss?
What is saw palmetto?
Saw palmetto is an extract from the berries of the serenoa repens palm.
Found in the subtropical southeastern United States, the berries are rich in fatty acids and phytosterols. The medicinal benefits of the serenoa repens berries have meant the plant has been used by various cultures, such as the Native Americans and the Mayans, to treat maladies ranging from urinary issues to problems with the reproductive system. More recently, it has been studied as a potential treatment for benign prostatic hyperplasia (BPH).
Interestingly, current hair loss treatments finasteride and dutasteride are also prescribed to treat BPH. Finasteride, for example, was originally developed for this purpose. It was only after doctors noted that patients treated for BPH started to grow thicker hair that the drug was adapted as a hair loss treatment.
The reason for this is that saw palmetto reduces levels of dihydrotestosterone (DHT), which is the main hormone implicated in androgenetic alopecia (male pattern baldness).
Prescription hair loss treatments such as finasteride and dutasteride also reduce DHT levels by lowering levels of the enzyme 5-alpha reductase (which converts testosterone to DHT). These prescription treatments are effective at slowing and even reversing the progression of hair loss in men. Unfortunately, many users also suffer side effects.
As a natural alternative, saw palmetto shows promise for treating hair loss without causing side effects.
Does it stop hair loss?
By reducing DHT levels, saw palmetto should – in theory – slow the progression of hair loss.
And clinical trials have demonstrated that saw palmetto does, in fact, reduce DHT levels. For example, this trial found that:
In the randomized trial, tissue DHT levels were reduced by 32% from 6.49 to 4.40 ng/g in the [saw palmetto] group (P <0.005), with no significant change in the placebo group. […] The [saw palmetto]-induced suppression of prostatic DHT levels, modest but significant in a randomized trial, lends an element of support to the hypothesis that inhibition of the enzyme 5-alpha reductase is a mechanism of action of this substance.
While not quite as effective as finasteride (which reduces DHT levels by around 70%), this is still a significant result. For those with mild androgenetic alopecia, reducing DHT levels by 32% is likely to be enough to significantly slow the progression of hair loss.
It’s worth noting, however, that other herbs – nettle root and pumpkin seed oil, for example – were used as well as saw palmetto in this trial.
But other trials have confirmed the efficacy of saw palmetto as an effective herbal hair loss treatment:
We can summarize our results by observing that Serenoa repens could lead to an improvement of androgenetic alopecia, while finasteride confirmed its efficacy. We also clinically observed, that finasteride acts in both the front area and the vertex, while Serenoa repens prevalently in the vertex.
And this trial also found saw palmetto to be effective:
The goal of this study was to test botanically derived 5AR inhibitors, specifically the liposterolic extract of Serenoa repens (LSESr) and beta-sitosterol, in the treatment of AGA. […] The results of this pilot study showed a highly positive response to treatment. The blinded investigative staff assessment report showed that 60% of (6/10) study subjects dosed with the active study formulation were rated as improved at the final visit.
As a natural herbal supplement which is used by millions of people worldwide, saw palmetto is very safe to use.
Side effects are rare, although some users report:
And because saw palmetto does reduce DHT levels, there is also the possibility of sexual side effects such as those associated with finasteride use.
Of course, incidence of side effects is extremely low, making saw palmetto a very safe hair loss treatment.
How much is needed?
In the trial where subjects saw a 32% reduction in DHT, they were taking 106mg of saw palmetto three times a day (318mg total).
However, many online vendors offer much higher dosages – it’s not uncommon to find 2000mg or even 3000mg tablets. Whether this has any additional benefits for hair loss is unclear though as there have been few studies which test this.
Should I take it?
Saw palmetto is not as effective as prescription hair loss treatments like finasteride or dutasteride.
However, there is strong evidence to suggest that it does have a positive effect on hair loss – albeit a mild one.
Trials have shown saw palmetto to have mild anti-androgenic effects, reducing DHT levels. This will have a positive effect on hair growth, even if it won’t completely halt the progression of androgenetic alopecia.
For this reason it’s well worth considering saw palmetto supplementation if you’re suffering from hair loss – especially if you’re unable to take finasteride (Proscar). DHT is the primary cause of hair loss in men so any reduction in DHT levels will have a positive effect on your hair.
What’s more, it’s less likely to cause side effects than prescription hair loss drugs. However, it’s also less effective.
For this reason, users will see the best results if they use saw palmetto in conjunction with other proven hair loss treatments.