Tribulus Terrestris for ED: Does It Really Work?

meta-analysis PMID: 37686709

Quick Summary: Research suggests Tribulus terrestris, a plant used in some supplements, might help with erectile dysfunction (ED). However, a recent study found that many supplements on the market don't contain enough of it to be effective.

What The Research Found

A recent study looked at whether supplements containing Tribulus terrestris could help with ED. The study found that Tribulus terrestris, along with other ingredients, showed promise in improving sexual function in some studies. However, when they looked at supplements sold in Italy, most didn't contain enough Tribulus terrestris to make a difference.

Study Details

Who was studied: The research combined data from multiple studies (a meta-analysis) and analyzed supplements sold in Italy.

How long: The original studies that were analyzed varied in length. The analysis of supplements was a snapshot of what was available on the market.

What they took: The research found that a dose of at least 6 mg/day of Tribulus terrestris might be needed to see results.

What This Means For You

Be cautious: While Tribulus terrestris could help, many supplements don't have enough of it.

Check the label: If you're considering a supplement, look for one that lists the amount of Tribulus terrestris and make sure it meets the minimum effective dose.

Talk to your doctor: Don't rely on supplements as your only treatment for ED. Talk to your doctor about the best options for you.

Study Limitations

Location matters: The study only looked at supplements sold in Italy, so the results might not apply everywhere.

Complex formulas: Many supplements have multiple ingredients, making it hard to know if Tribulus terrestris is the only thing helping.

Dose is key: The study didn't always specify the exact dose used in the original studies.

Key Findings

The study identified Tribulus terrestris, alongside Panax ginseng and L-arginine, as nutraceuticals with potential efficacy in improving male sexual function based on a meta-analysis of randomized controlled trials (RCTs). However, when analyzing 25 marketed dietary supplements (DSs) in Italy, only 2 products (8%) met criteria for higher expected efficacy, while 80% (n=20) showed no expected efficacy due to suboptimal dosing or lack of evidence. The authors concluded that most DSs for erectile dysfunction (ED) are unlikely to provide clinically meaningful benefits despite containing ingredients with theoretical promise.

Study Design

This 2023 meta-analysis combined a systematic review of RCTs evaluating nutraceuticals for ED with an analysis of 25 DS products available in Italy. The systematic review assessed efficacy of individual ingredients, while the product analysis used a scoring system to categorize supplements into high, low, or no expected efficacy clusters. The meta-analysis aggregated data from prior trials (sample sizes unspecified in the summary), but the supplement analysis focused on label dosing and ingredient composition.

Dosage & Administration

The meta-analysis determined a minimal effective daily dose (mED) of 6 mg/day for Tribulus terrestris. In the Italian supplement analysis, most products contained lower-than-mED doses or combinations of ingredients without synergistic evidence. Administration protocols in RCTs (e.g., duration, formulation) were not detailed in the provided summary.

Results & Efficacy

Tribulus terrestris demonstrated statistically significant improvements in erectile function in pooled RCT data, though specific effect sizes (e.g., standardized mean differences, confidence intervals) were not reported in the summary. The Italian supplement analysis revealed no products containing Tribulus terrestris at the mED of 6 mg/day, and only 2 supplements across all ingredients achieved the highest efficacy cluster. The majority (80%) of products scored poorly due to insufficient dosing or unproven ingredient blends.

Limitations

Geographic specificity: Supplements analyzed were limited to the Italian market, limiting generalizability.
Combination complexity: Most DSs included multi-ingredient blends, making it difficult to isolate Tribulus terrestris’ individual efficacy.
Heterogeneity: The meta-analysis did not quantify variability in study designs, populations, or formulations.
Lack of mechanistic data: The summary did not detail biological pathways or pharmacokinetic evidence for Tribulus terrestris.
No clinical endpoints: The supplement scoring system relied on ingredient doses rather than direct measures of ED improvement.

Clinical Relevance

For supplement users, this study suggests that most commercially available DSs for ED—including those containing Tribulus terrestris—are unlikely to be effective due to inadequate dosing or unproven combinations. While Tribulus terrestris showed promise in RCTs, consumers should verify products provide at least the mED of 6 mg/day and prioritize formulations with evidence-based dosing. Clinicians should caution patients against relying on DSs as first-line therapy for ED, emphasizing the need for standardized clinical treatments and further research on optimal nutraceutical combinations.

Source: PubMed | Date: 2023 | Study Type: Meta-analysis & systematic review.