People who want to boost their testosterone levels naturally might consider using saw palmetto. Saw palmetto is an herbal remedy that comes from the fruit of the Serenoa repens plant. Some research suggests that saw palmetto can help manage some aspects of male reproductive health, including prostate problems.

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There is a lot of conflicting information available about the link between saw palmetto and testosterone. Many people believe that saw palmetto can boost testosterone levels, but others disagree.

Is there any truth to this idea, and does saw palmetto affect male health in any other ways? Learn more in this article.

Researchers have looked into a variety of roles that saw palmetto might play in male health. Here, we look at eight of the facts and myths surrounding saw palmetto.

1. Fact: Saw palmetto is linked to testosterone levels

Scientists have found that saw palmetto can slow down 5-alpha reductase. This enzyme converts testosterone into a potent androgen hormone called dihydrotestosterone (DHT). Androgen hormones regulate the development of male characteristics.

The production of androgen hormones occurs in the testes (in males), ovaries (in females), and adrenal glands. These hormones are also responsible for the development of primary sex organs in the womb and secondary male characteristics during puberty.

By slowing down 5-alpha reductase, saw palmetto could reduce the effects of DHT as males get older.

Although proponents of saw palmetto claim that it helps regulate testosterone levels, there is little evidence to confirm this. Much of the research into the connection between saw palmetto and testosterone levels is also very outdated.

One old report of multiple studies on saw palmetto in the Journal of the International Society of Sports Nutrition did find that males taking saw palmetto over a 2-week period had higher levels of testosterone than those in the placebo control group.

However, there have not been enough studies since to either counter or confirm these findings.

2. Fact: Saw palmetto may help reduce benign prostatic hyperplasia symptoms

Benign prostatic hyperplasia (BPH) is a noncancerous condition that causes an enlarged prostate. The prostate is a small gland that sits just below the bladder. It is part of the male reproductive system.

An enlarged prostate puts pressure on the urethra, which is the long tube inside the penis that is responsible for draining urine from the bladder. BPH can be uncomfortable, as it makes it harder to urinate even when the need is urgent. It can also make it difficult to empty the bladder completely and can cause leaking after urination.

Several small studies investigating saw palmetto as a treatment for the symptoms of BPH have shown modest results. For example, at least one study has suggested that saw palmetto is beneficial in combination with other natural therapies to treat these symptoms.

A double-blind, randomized study from 2011 divided 369 men into two groups. One group took up to three times the standard daily dose of saw palmetto, while the other group took a placebo. The results showed that saw palmetto was no more effective than the placebo in reducing the lower urinary tract symptoms of BPH.

In addition, a 2012 Cochrane review of 32 randomized controlled studies showed that taking a double or triple dose of saw palmetto did not lead to an improvement in prostate size or urinary symptoms in males with BPH.

A 2014 randomized study of 225 males looked at the effectiveness of using a combination of saw palmetto, lycopene, selenium, and tamsulosin to treat symptoms of BPH. The combination therapy was more effective than the single treatments and did not appear to cause any adverse events.

3. Fact: Saw palmetto can improve sex drive

Having low testosterone levels reduces sex drive, or libido. Some people believe that saw palmetto can help improve libido by reducing testosterone breakdown, and there is some evidence to support this.

A study in the journal Urologia Internationalis found that males using saw palmetto experienced improved sexual function. In the study, which involved 120 males with enlarged prostate glands, the researchers monitored the following over a 2-year period:

  • urine flow
  • blood prostate-specific antigen
  • prostate symptoms
  • erectile function
  • quality of life

They found that using saw palmetto improved prostate symptoms and sexual function after 2 years. This improvement was significant, especially in the first year.

4. Unconfirmed: Saw palmetto can help prevent prostate cancer

Prostate cancer affects around 1 in 8 males in the United States, according to the American Cancer Society (ACS). The ACS also estimates that there will be around 34,130 deaths from prostate cancer in 2021.

Research has suggested that DHT may contribute to the development of prostate cancer. Therefore, it is possible that saw palmetto might help prevent this condition by slowing down the conversion of DHT.

Prescription medications can also slow down this conversion, but they often have severe side effects. Saw palmetto may inhibit DHT without causing serious side effects.

However, there is no strong research to support the claim that saw palmetto can prevent prostate cancer.

5. Myth: Saw palmetto improves fertility

Some couples who are unable to conceive have tried taking saw palmetto to improve the likelihood of conception. The common belief is that saw palmetto increases sperm count in males and promotes healthier eggs in females.

However, there is no substantial evidence to suggest that saw palmetto can improve fertility.

6. Fact: Saw palmetto can reduce male hair loss

It is normal for hair to fall out and grow back. However, having high levels of DHT can reduce hair growth. As a result, some people believe that using saw palmetto may help prevent hair loss.

The research into saw palmetto and hair growth is varied yet somewhat limited, but there are studies indicating that the plant extract might show some promise as a treatment.

One study in mouse models found that saw palmetto promoted hair regeneration and repaired hair loss by activating the signaling pathways responsible for hair growth.

A small 2014 study of 25 males showed positive results when the participants used topical saw palmetto and 10% Trichogen as a treatment. The study showed an 11.9% hair count increase after 4 months.

A second small study of 50 males confirmed the effectiveness of topical saw palmetto for treating male baldness. Hair count increased at weeks 12 and 24 compared with the baseline.

7. Myth: Saw palmetto does nothing for females

Saw palmetto research has often focused on male health, so many people believe that it cannot benefit females.

However, there is some evidence to suggest that saw palmetto may help regulate specific female hormones. For example, it may have an estrogen-like effect and balance out the effects of testosterone.

Saw palmetto may also help reduce high levels of androgens and prolactin in females with polycystic ovary syndrome (PCOS). Females with PCOS have elevated levels of male hormones. This causes a specific set of symptoms, including irregular or heavy menstrual periods, excess body and facial hair, and acne.

Many of the studies into this topic have been in animals, so they cannot confirm a link between PCOS and saw palmetto in humans. However, they are still helpful, as they show that saw palmetto can block prolactin receptors on ovarian cells that are overexpressing them. The regulation of these receptors may help reduce the symptoms of PCOS.

8. Myth: Saw palmetto has no side effects because it is a plant

Many people believe that because saw palmetto is a plant, it will not cause side effects. However, saw palmetto can cause side effects, including:

Saw palmetto may also cause adverse effects in people taking anticoagulants, birth control pills, or iron supplements.

Much of the information about saw palmetto safety comes from studies in males. For this reason, researchers know little about the side effects of saw palmetto in females and children.

The majority of studies have suggested that saw palmetto might be beneficial to prostate health, especially in males with BPH. However, there is limited research confirming a positive effect on testosterone levels.

As with any supplement, it is a good idea to discuss the use of saw palmetto with a doctor first. Although it is safe for most healthy adults, some people have reported side effects. Saw palmetto may also interfere with other medications.

The Food and Drug Administration (FDA) does not monitor the quality and purity of herbs, so it is possible for marketed herbs to contain toxic metals and other contaminants.