Does Saw Palmetto really work for Prostate Health and Hair Loss?


Can you use Saw Palmetto for Prostate Health?

Some studies show that saw palmetto contains plant-based chemicals that may support prostate health by reducing the symptoms of benign prostatic hyperplasia (BPH) in many ways:

  • it blocks the spread of an enzyme that promotes the growth of prostate cancer cells by deactivating specific receptors
  • it might stop the growth of the prostate or even shrink it
  • it may affect body levels of testosterone
  • it has anti-inflammatory effects on the prostate when combined with lycopene and selenium
  • it shrinks the inner lining that puts pressure on the ureters (tubes that carry urine from the kidneys to the bladder)

In the video below, Dr. David Samadi explains how saw palmetto may help reduce inflammation, prostatitis, and testosterone levels which could help in shrinking of the prostate.

This is our recommended Saw Palmetto supplement (Amazon’s Choice):

Sundown Naturals Saw Palmetto 450 mg, 250 Capsules

What is Saw Palmetto’s scientific name?

Saw Palmetto’s scientific name is Serenoa Repens. It is a member of the Palm family (Arecaceae). Other scientific names for Saw Palmetto include:

  • Serenoa serrulatum
  • Serenoa serrulata
  • Sabal serrulata
  • Brahea serrulata
  • Corypha repens

What is the recommended dosage of Saw Palmetto for the Prostate?

The typical saw palmetto dosage for the prostate depends on the form of the supplement:

  • Dried form or oil extract: 160 mg twice daily or 320 mg once daily
  • Whole berries: 1 to 2 g daily
  • Permixon: 320 mg

As with most herbal supplements, the recommended dosage may vary because of the lack of standardization of herbal supplement products.

How long does it take for Saw Palmetto to shrink the Prostate?

Saw Palmetto can generally take around 4 to 6 weeks to start shrinking the Prostate, and it may take up to 8 weeks to see this effect.

Study Information

  • Title: Randomized, double-blind, placebo-controlled trial of saw palmetto in men with lower urinary tract symptoms
  • Length: 7 months.

Subject Information

  • Number of Subjects: 85.
  • Gender: Male.
  • Age group: 45 or older.
  • Health condition: Prostate Symptoms.

Method used

After a 1-month placebo run-in period, 85 men were randomized to receive saw palmetto or placebo for 6 months.


The symptoms decreased in the saw palmetto group compared to the placebo group.

  • The quality-of-life score improved to a greater degree in the saw palmetto group, but this difference was not statistically significant.
  • No change occurred in the sexual function questionnaire results in either group.
  • The peak urination flow rate increased by 1.0 mL/s and 1.4 mL/s in the saw palmetto and placebo groups. 


  • Saw palmetto led to a statistically significant improvement in urinary symptoms in men with lower urinary tract symptoms compared with placebo.
  • Saw palmetto had no measurable effect on the urinary flow rates. The mechanism by which saw palmetto improves urinary symptoms remains unknown.

Prostataplex Supplement Studies

Prostataplex is a mix of herbal supplements including Saw Palmetto. It improves lower urinary tract symptoms associated with BPH.

  • In one study, 46 men took 2 capsules daily of Prostataplex for 12 weeks
  • In another study, 39 men were administered Prostataplex orally for 12 weeks
  • In both studies, Prostataplex had positive effects on improving symptoms and quality of life in men with mild to moderate BPH.

Prostataplex Study 1

  • Title: Effect of saw palmetto soft gel capsule on lower urinary tract symptoms associated with benign prostatic hyperplasia: a randomized trial in Shanghai, China
  • Length: 12 weeks.

Subject Information

  • Number of Subjects: 92.
  • Gender: Male.
  • Age group: 49-75.
  • Health condition: lower urinary tract symptoms.

Method used

The 46 patients in the intervention group were given 2 Prostataplex soft gels daily for 12 weeks, while the 46 in the control group were given 2 placebo soft gels for the same time.


  • The treated and control groups appeared to have more than a 95% compliance rate, as judged by counting the remaining pills in the bottle collected at the end of trial months 1 to 3.
  • After 12 weeks of intervention the mean maximum urinary flow rate was significantly higher in the treatment group than in the control group, while relative urinary resistance was significantly lower in the treatment group than in the control group.
  • While there was no significant difference in mean prostate volume or Prostate Symptoms between the 2 groups, 18 of 46 patients (39.1%) in the treatment group showed a Prostate Symptom improvement after intervention, whereas only 1 of 46 (2.2%) in the control group showed a Prostate Symptom improvement.


Prostataplex may have short-term effects in improving symptoms and objective measures in Chinese men with lower urinary tract symptoms associated with benign prostatic hyperplasia.

While these studies are promising, they were of short duration (3 months or less), so researchers cannot say for sure whether saw palmetto is truly effective for preventing symptoms of BPH. More research is needed to determine the effectiveness of saw palmetto for this condition.

Prostataplex Study 2

  • Title: Saw Palmetto-Based Nutritional Supplement Prostataplex Relieves Symptoms of Benign Prostatic Hyperplasia (BPH) in Patients with Mild to Moderate BPH
  • Length: 12 weeks

Subject Information

  • Gender: Male.
  • Number of Subjects: 80
  • Health condition: mild to moderate degrees of benign prostatic hyperplasia (BPH).

Method used

  • Eighty patients with BPH were randomly assigned to either the intervention group (39 cases) or control group (41 cases).
  • Patients in the intervention group were administered Prostataplex orally and placebos were given to patients in the control group.
  • The duration of treatment was 12 weeks in both groups.


  • Following the intervention of Prostataplex, the maximum urinary flow rates (MFR), total scores of International Prostate Symptom Score (IPSS) and quality of life indicators were significantly better among the patients in the intervention group than those in the control group.
  • Significant improvement of symptoms including dysuria, reducing nocturnal polyuria and increasing urinary flow rate was seen after two months of intervention, especially for the improvement of incomplete bladder emptying.


Prostataplex has positive effects on improving symptoms as well as quality of life in men with mild to moderate BPH.

Is Topical Saw Palmetto beneficial for Hair Loss?

In several studies, the use of Topical Saw Palmetto has led to the following benefits for Hair Loss:

  • 35% increase in hair density
  • 67% reduction in scalp sebum
  • 11.9% increase in total hair count
  • 60% improvement in overall hair quality
  • 52% of the patients stabilized hair loss progression

Saw Palmetto can be found in hair care products like serum, shampoo, lotion, and powder that can be applied topically to the scalp and hair. When using Topical Saw Palmetto twice weekly, hair loss benefits can be seen after 4 months.

Topical Saw Palmetto is well tolerated and not associated with serious side effects in patients with hair loss. Further studies are needed to confirm its efficacy and determine long-term side effects.

Study 1 Information

  • Title: Treatment of male androgenetic alopecia with topical products containing Serenoa repens extract
  • Length: 24 weeks.

Subject Information

  • Number of Subjects: 50.
  • Gender: Male.
  • Age group: 20-50.
  • Health condition: lower urinary tract symptoms.

Method used

  • In all, 50 male volunteers received topical S. repens products for 24 weeks.
  • The primary end-point was a hair count in an area of 2.54 cm(2) at week 24.
  • Secondary end-points included hair restoration, investigators’ photographic assessment, patients’ evaluation and discovering adverse events.


  • The average hair count and terminal hair count increased at weeks 12 and 24 compared to baseline.
  • Some of these positive results levelled off at week 24, presumably because the concentrated topical product containing S. repens extract was stopped after 4 weeks.
  • The patients were satisfied with the products and the side-effects were limited.


The topical application of S. repens extract could be an alternative treatment in male pattern baldness in male patients who do not want or cannot tolerate the side-effects of standard medications, but the use of a concentrated S. repens product beyond 4 weeks may be necessary for sustained efficacy.

Study 2 Information

  • Title: The Evaluation of Efficacy and Safety of Topical Saw Palmetto and Trichogen Veg Complex for the Treatment of Androgenetic Alopecia in Men
  • Length: 4 months.

Subject Information

  • Number of Subjects: 25.
  • Gender: Male.
  • Health condition: Androgenetic alopecia.

Method used

  • Male patients, who treated with topical saw palmetto and trichogen veg complex (TVC) for four months between 2011-2012 were included to our study.
  • Among the patient files, records of 25 patient were accepted available and taken into consideration


  • Total hair count was increased 11.9% compared with the pretreatment period.
  • The final ratio of anagen/telogen hair was compared with the initials and the increase in ratio was 38%.
  • The observers declared that enhancement was noted in 48% of the patients and no difference was not noted in 36% of the patients.


At the end of the study, topical saw palmetto and trichogen veg complex (TVC) were evaluated efficient and safe for the treatment of AGA. Randomized controlled trials among patient groups will reveal more conclusive data associated with topical saw palmetto and TVC.

Can Saw Palmetto block 5 alpha reductase?

Studies suggest that the berries of Saw Palmetto can help block the activity of both types of 5 alpha reductase (types 1 & 2), due to their high content of lauric acid, myristic acid, and oleic acid, which may be the main fatty acids responsible for its mechanism of action. The 5 alpha reductase inhibition activity of 1mg finasteride is equal to 18000mg Saw Palmetto.

5 alpha reductase is an enzyme that converts testosterone into a potent androgen hormone called dihydrotestosterone (DHT). DHT is linked to hair loss and also the enlargement of the prostate.

Study Information

  • Title: A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of 5-alpha-reductase in the treatment of androgenetic alopecia

Subject Information

  • Gender: Male.
  • Age group: 23-64
  • Health condition: mild to moderate Androgenetic alopecia.

Method used

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.


This study establishes the effectiveness of naturally occurring 5AR inhibitors against AGA for the first time, and justifies the expansion to larger trials.

How long does Saw Palmetto stay in your system?

A single 320mg dose of Saw Palmetto has been reported to stay in your system for 1.69 hours on average (ranging from 1.26 to 2.15 hours), and is eliminated from your system after 1.9 hours on average.

What are the Side Effects of Topical Saw Palmetto?

Topical products containing Saw Palmetto extract could cause minor side effects including:

  • cold sensation
  • mild burning
  • unpleasant smell
  • itchy scalp
  • acne on the forehead
  • allergic contact dermatitis

Can Saw Palmetto cause damage to the Liver?

The National Institute of Diabetes and Digestive and Kidney Diseases says that there is not enough information to conclude that Saw Palmetto is the actual cause of any liver side effects, so its specific role on this regard remains unknown. On medical terms, Saw Palmetto has a liver injury Likelihood Score of “D” (possible or rare cause of liver injury).

  • None of the components on Saw Palmetto has been shown to be toxic to the liver
  • The use of Saw Palmetto has not been linked to liver enzyme increase
  • Studies found little or no evidence of liver injury from its use

However, there have been two rare case reports of liver damage in people who took Saw Palmetto, although other possible causes of liver disease were present, so the exact cause of these side effects was not determined.

According to the National Institutes of Health, any liver side effects of Saw Palmetto are similar to those of hepatitis, with onset occurring within 2 weeks and clearing within 1 to 3 months.

The use Saw Palmetto is not recommended if you have a history of pre-existing liver diseases or are at an increased risk for them.

Does Saw Palmetto cause high blood pressure?

There have been rare reports of side effects including high blood pressure, but it’s not clear if it was actually caused by Saw Palmetto.

According to Jordana B. Cohen, MD (assistant professor of medicine at the Hospital of the University of Pennsylvania in Philadelphia), there’s no research that shows that Saw Palmetto can help reduce high blood pressure.

Can you take Saw Palmetto and Aspirin at the same time?

Do not take Saw Palmetto without medical advice if you are using medications and herbal supplements with blood thinning effects such as Aspirin.

Saw Palmetto may affect the blood’s ability to clot, and increases the toxicity of Aspirin by an unspecified interaction mechanism. This combination may increase the risk of bleeding.

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This article makes use of information from the U.S. National Library of Medicine under the terms of the Creative Commons Attribution 4.0 International License.

Does Saw Palmetto really work for Prostate Health and Hair Loss?
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