1. Prevents Hair Loss

Hair loss is a common condition that can be caused by a variety of factors, including genetics, certain medical conditions, hormonal changes, and the use of medications, such as stimulants and blood thinners (1).

Saw palmetto is often used to balance hormone levels and combat hair loss.

According to one review, saw palmetto may help block the activity of 5-alpha reductase (5α-R), an enzyme that converts testosterone into a hormone linked to hair loss called dihydrotestosterone (DHT).

It may also prevent hair loss by reducing the uptake of DHT in the hair follicles, which decreases its ability to bind to specific hormone receptors (2).

In one study, saw palmetto was effective at improving hair growth in 60% of men with male pattern baldness between the ages of 23 and 64 (3).

Another study in 62 adults showed that applying saw palmetto topically for 3 months increased hair density by 35% (2).

Summary

Saw palmetto may ward off hair loss and increase hair density by decreasing levels of a specific enzyme related to hair loss.

2. Improves urinary tract function

Urinary tract symptoms are common among older men and can include issues like incontinence and difficulty urinating (4).

Saw palmetto may improve urinary symptoms associated with benign prostate hyperplasia (BPH) — a condition that causes an enlargement of the prostate gland and results in decreased urine flow.

One 12-week study in 92 men showed that taking two capsules daily of Prostataplex, a mix of herbal supplements that includes saw palmetto, helped improve urinary tract symptoms associated with BPH (5).

Similarly, another study in 85 men over the age of 45 found that treatment with 160 mg of saw palmetto twice daily reduced lower urinary tract symptoms, increased urine flow, and improved overall quality of life after 6 months (6).

However, more research is needed to determine whether saw palmetto may also improve urinary tract function in the general population, including for those without prostate issues.

Summary

Saw palmetto may improve urinary tract function and could aid in the treatment of urinary tract symptoms caused by BPH. Still, more research is needed.

3. May Support Prostate Health

The prostate is a small gland located between the bladder and the penis in men, which is responsible for maintaining sperm health (7).

Some research suggests that saw palmetto could support prostate health and may aid in preventing issues like BPH and prostate cancer.

According to one test-tube study, saw palmetto berry extract was able to decrease the growth of prostate cancer cells (8).

Another test-tube study showed that saw palmetto blocked the spread and growth of prostate cancer cells by deactivating specific receptors involved in cancer development (9).

Other human and animal studies indicate that it may be effective at reducing urinary symptoms and inflammation related to BPH as well (5, 6, 10).

Yet, some studies don't associate saw palmetto with a lower risk of prostate cancer and observe that it may be ineffective at decreasing symptoms of BPH (11, 12, 13).

Further high-quality research is needed to evaluate how saw palmetto may affect prostate health in humans.

Summary

Test-tube studies show that saw palmetto may help decrease the growth of prostate cancer cells. It may also help improve symptoms of BPH, but research is inconclusive.

4. May Decrease Inflammation

Saw palmetto contains the antioxidants epicatechin and methyl gallate — compounds that prevent damage to cells, decrease inflammation, and protect against chronic disease (14, 15).

Some research shows that saw palmetto may have anti-inflammatory properties, which could be beneficial in treating certain conditions.

For example, one study observed that giving saw palmetto extract to mice with enlarged prostate glands decreased swelling and several markers of inflammation, including interleukin 6 (IL-6) (10).

Another study in obese rats with BPH found that saw palmetto was effective at decreasing inflammation and improving antioxidant status (16).

Although these results are promising, additional studies are needed to determine how saw palmetto may impact inflammation in humans.

Summary

Saw palmetto is high in antioxidants and has been shown to decrease inflammation in some animal studies. Nonetheless, more high-quality human studies are needed.

5. May Help Regulate Testosterone Levels

Saw palmetto is often used by men looking to boost testosterone levels naturally.

Regulating testosterone levels can impact several aspects of health, including body composition, sex drive, mood, and cognition (17).

Testosterone levels decline with age, and some research shows that low levels of testosterone could contribute to conditions like heart disease (18).

Saw palmetto works by decreasing the activity of 5α-R — an enzyme responsible for converting testosterone to dihydrotestosterone (DHT), another sex hormone, to help preserve testosterone levels in the body (19).

One test-tube study found that the effectiveness of saw palmetto extract was comparable to finasteride in preserving testosterone levels. Finasteride is a medication used to treat hair loss and BPH by reducing the activity of 5α-R (20).

Another study in 40 men observed that treatment with saw palmetto decreased levels of DHT by 32% after 6 months, suggesting that saw palmetto was effective at maintaining testosterone levels (21).

Summary

Test-tube and human studies show that saw palmetto could decrease the activity of an enzyme that converts testosterone to DHT, helping to maintain testosterone levels naturally.

Forms and Dosage Recommendations

Saw palmetto is widely available in supplement form, making it incredibly easy to add to your daily routine.

It comes in capsule, softgel, and tablet form and is often combined with other ingredients that help enhance prostate health, such as pumpkin seed extract (22).

Less commonly, it can also be found in ground, dried, liquid extract, or powdered tea form.

Most research is conducted using saw palmetto in dosages of 320 mg per day, often divided into two doses.

Some recommend taking the supplements with food, which can help minimize digestive issues and prevent adverse side effects.

Summary

Saw palmetto is available in capsule, softgel, and tablet form, which can be taken in doses of 320 mg per day. It can also be found in ground, dried, liquid extract, or tea form.

Potential Side Effects

Saw palmetto is generally considered safe and has been associated with very few side effects.

Some of the most commonly reported side effects of saw palmetto in research studies include headache, dizziness, nausea, and constipation (23).

Note that saw palmetto is not recommended for everyone.

For example, women who are pregnant or breastfeeding should avoid taking saw palmetto, as it may impact hormone levels (24).

Because it may alter hormone levels, saw palmetto may not be suitable for those taking hormone replacement therapy or hormonal contraceptives either. More research is needed to evaluate its potential effects (25).

Saw palmetto may also interfere with blood-thinning medications, such as warfarin or Coumadin, which can increase bleeding risk (26).

If you have any underlying health conditions, are taking certain medications, or are pregnant or breastfeeding, be sure to consult with your healthcare provider before supplementing with saw palmetto.

Summary

Saw palmetto may cause mild side effects and should not be taken by those on certain medications or women who are pregnant or breastfeeding.

The Bottom Line

Saw palmetto is a species of palm used to produce a supplement that's packed with health benefits.

Promising research shows that saw palmetto may help increase testosterone levels, improve prostate health, reduce inflammation, prevent hair loss, and enhance urinary tract function.

However, some studies have turned up mixed results on its effectiveness. Additional large-scale human research is needed to understand how saw palmetto can impact health.