Does Saw Palmetto Boost Testosterone? Know Scientific Facts

Saw palmetto is an herbal medicine derived from the fruit of the American dwarf palm tree. Traditional uses include supporting prostate health and urinary tract issues in older men. However, theories also exist that saw palmetto may assist reproductive health by directly stimulating testosterone production. In this evidence-based article, we analyze the latest science regarding saw palmetto supplements and male androgen levels.

Saw Palmetto Mechanisms – What Does It Do?

To understand theories around saw palmetto and testosterone, it’s important to know proposed mechanisms of action. Being rich in plant sterols and fatty acids, saw palmetto is considered an anti-androgen similar to some prescription drugs. Research shows it may inhibit certain enzymes and receptors involved in uptake and conversion of testosterone, particularly in prostate tissues. So while not directly boosting testosterone, potential pathways exist for saw palmetto to indirectly raise levels by reducing cellular uptake, slowing conversion to DHT and limiting negative feedback signals back to production glands. However, current evidence whether these mechanisms translate to meaningful testosterone changes in men remains highly contentious. 

Key Mechanisms:

– Contains plant sterols/fatty acids that inhibit androgen pathways

– May limit testosterone conversion and uptake specifically in prostate

– Could mildly raise overall testosterone via feedback loops

– Unclear if effects are enough to impact levels 

Early Promising Evidence

A promising Italian study in 2009 provided initial clinical evidence for the testosterone theories. Researchers gave men with non-cancerous prostate enlargement (BPH) 320mg saw palmetto extract over 2 months. Encouraging results showed a statistically significant 20% improvement in the ratio between free testosterone and overall testosterone. However, actual free and total testosterone levels didn’t increase compared to baseline. So while an interesting signal, evidence remained flimsy for meaningful testosterone changes that could impact health or function.

Key Details on Early Evidence:

– Men with BPH supplemented saw palmetto extract

– Improved ratio of free testosterone but no actual level increases

– Interesting but not enough to demonstrate meaningful impacts

Follow-Up Studies Find No Effect

Unfortunately, multiple higher-quality blinded trials since cast strong doubts over the 2009 findings. A detailed 6-month trial on saw palmetto given to 25 healthy men could not replicate any testosterone elevating effects. No changes occurred in total, free or bio available testosterone levels compared to supplemented matched controls. Four other well-controlled clinical experiments using up to triple the doses given in 2009 similarly found zero impact on any male hormone biomarker over 6 months. Finally, the most recent 2021 meta-analysis combined data from over 300 middle-aged subjects, conclusively finding saw palmetto supplements do not alter testosterone profiles. So despite promising mechanisms and initial findings, follow-up evidence firmly nullifies impacts on androgen production.

Key Details From Follow-Up Studies:

– High quality 6-month trial showed no testosterone changes

– 4 other controlled experiments using triple doses also found zero impact  

– Hundreds of men analyzed – saw palmetto doesn’t raise testosterone

No Libido or Performance Enhancement Either

Considering saw palmetto doesn’t raise testosterone, research unsurprisingly also finds no enhancement of sexual function or libido in supplemented groups. Additional clinical data shows saw palmetto does not heighten arousal, boost erectile function, improve intercourse satisfaction or enhance orgasm performance compared to men not using the herb. So despite some weak initial findings, all quality evidence to date demonstrates saw palmetto delivers no assist with vitality or virility for otherwise healthy men. Appropriate medical support should still be sought where sexual issues cause distress. 

Reproduction Research Details:

– Doesn’t heighten libido or arousal 

– Zero enhancement of erectile function

– No improvement in orgasm performance

– Seek qualified medical help for sexual issues

May Still Aid Prostate Health

While falling short for hormones and reproduction, higher saw palmetto doses around 320mg may offer prostate benefits. Some analysis indicates mild improvement in urinary symptoms, flow rates and reduced nighttime bathroom visits – potentially via anti-inflammatory effects. So there still appear prostate protective qualities – but no knock-on upgrades to testosterone or virility. Any prostate issues should receive proper medical assessment rather than self-supplementation alone.

Takeaway for Prostate Health:

– May still provide mild prostate symptom relief

– No direct testosterone benefits though

– See a doctor for any troubling prostate symptoms 


In summary, while saw palmetto shows anti-androgenic mechanisms that could plausibly assist testosterone production, follow-up clinical data wholly disputes early claims. No quality evidence now backs saw palmetto to modify hormone profiles or enhance sexual health. Some prostate relief remains possible but requires diagnosis rather than self-supplementation. For improving low libido, erectile function or testosterone levels, seek professional medical advice on evidence-based treatments instead of this herbal alternative lacking proper research support.