What is Saw Palmetto?

Saw palmetto is an extract from the fruit of the plant, Serenoa repens, a type of palm that grows abundantly in the south-east United States. Whilst it has been used as a part of folk medicine for potentially hundreds of years, it was only added to Florida’s list of commercially important plants in 2018.

This is partly because people have begun to exploit the rumours of the plant’s therapeutic benefits. Alongside treating low-T, it has been claimed that saw palmetto can improve the function of your urinary tract, that it can be used as an anti-inflammatory, and that it can be useful in treating an enlarged prostate. The US Food and Drug Administration has not approved it for medical use in any of these cases.

It is the berries that are the important bit, with extracts from the fruit usually being sold as a dietary supplement, as a tablet or in a tea or infusion. Some people also ingest the fruit dried, ground, or whole. Many people swear by it to help the symptoms of low-T. However, science doesn’t seem to agree.

What are the Signs of Low Testosterone?

Low testosterone is a condition that can affect men of all ages. However, it is generally experienced by those who are overweight, those with diabetes, and those who are older – as testosterone levels naturally decline with age.

Testosterone is the chemical that gives us our male physical characteristic; quite simply, it’s this that makes men male. As a result, low-T can be quite a difficult condition to deal with. Men are often reluctant to talk about the issue – whilst online vendors are eager to exploit that reluctance.

Anyone who is concerned that they may have the condition can look out for the major symptoms of low testosterone. These can include any of the following:

Erectile dysfunction and low libido. Whilst it is not clear precisely what role testosterone plays in the process of erections, men with low testosterone often struggle to achieve an erection. They can also have a reduced desire for sex too.

Mood swings. Low testosterone can cause depression, irritability, fatigue, and mood swings. Long periods of general malaise can be a sign that you have low testosterone too.

Reduced muscle mass and changed body composition. Low testosterone can lead to weight gain and decreased muscle mass. You may feel weaker, whilst it is possible that fat can increase on your chest.

Hair loss. It is possible that men with low testosterone will experience a loss of hair – not just on their head, but all over their body too.

Can Saw Palmetto Increase Testosterone Levels?

Its avowed ability to tackle low-T is one of the main selling points of saw palmetto. Whilst this idea has gained a lot of traction online, however, there is no strong scientific evidence that saw palmetto actually affects the levels of testosterone in the male body.

A study from 1988, for example, found that saw palmetto had no effect on hormone levels in men. Similarly, a 2014 study tested the effect on testosterone of a dietary supplement combining saw palmetto and an antioxidant known as astaxanthin. No statistically significant effect was found.

Interestingly, a 2008 study did find that the same dietary supplement increased testosterone levels. However, no placebo control was included in the study – which makes it difficult to say whether it was in fact the supplement that caused the testosterone increase at all.

Whilst these studies found no direct link between saw palmetto and testosterone levels, that’s not to say it’s necessarily useless. Rather, it’s to say that we don’t yet know for sure.

Other studies may have found a link between saw palmetto and a different hormone, dihydrotestosterone (or DHT), which is produced from testosterone by an enzyme known as 5α-Reductase. A study found, for example, that saw palmetto may block the activity of 5α-Reductase, whilst another seemed to confirm that it reduces testosterone’s conversion into DHT.

This, however, doesn’t prove that saw palmetto increases testosterone levels, as some sites claim. Rather, it means that scientists studying the plant have a bit more work to do.

Saw Palmetto, DHT, and Hair Loss

The link between the plant and DHT, however, is a potentially promising sign for those interested in saw palmetto’s possible effects on hair loss. But hold your horses: nothing is yet confirmed – and the plant remains unlicensed for medical use.

DHT is the hormone responsible for male pattern baldness (MPB). In most men, the hair follicles on your scalp are sensitive to the hormone. As DHT is produced, it binds to the follicles and causes them to weaken and shrink as a result. In those men who are genetically predisposed, the follicles can consequently become permanently damaged and stop producing hair at all.

Some studies have suggested that saw palmetto may be useful in tackling MPB. In one study, treatment with an extract from the plant produced an increase in hair coverage in nearly 40% of cases. Another found that just under half of cases saw hair coverage improve, generally by about 10%.

It’s not a bad rate for a humble plant. However, there are licensed medicines that work much better. Finasteride, for example, works in 90% of men, on exactly the same principle (it’s a 5α-Reductase inhibitor too). Meanwhile, Minoxidil improves hair coverage in over two thirds of those who use it. However, if you are after something natural, there’s no harm in trying saw palmetto at all.

Key Takeaways…

Science doesn’t seem to support the claim that saw palmetto increases testosterone levels. The studies that we have don’t show that saw palmetto has a hugely significant effect on our hormones.

That includes DHT, the hormone produced from testosterone that is responsible for hair loss in men. Whilst saw palmetto appears to act to block 5α-Reductase, the enzyme responsible for DHT’s production, licensed medications are a much more credible option if you are looking for reliable results.

While we've ensured that everything you read on the Health Centre is medically reviewed and approved, information presented here is not intended to be a substitute for professional medical advice, diagnosis, or treatment. It should never be relied upon for specific medical advice. If you have any questions or concerns, please talk to your doctor.