One ingredient, in depth

Tribulus Terrestris And Testosterone: What Twenty-One Men Showed

Tribulus terrestris has one of the biggest reputations in the aisle and one of the thinnest testosterone records, and this label prints the wrong Latin name beside it. Here are the plant, the trials and the arithmetic.

By Horse Peak Gelatin Team · Last updated September 26, 2026 · 10 min read · One ingredient, in depth

The row, and the Latin name that does not belong to it

The panel line reads Tribulus Terrestris Extract 10:1 (Trigonella foenum-graecum L.) — 100 mcg. The words before the bracket name one plant and the binomial inside the bracket names a different one: Trigonella foenum-graecum is fenugreek, and it is printed correctly two lines above, against the fenugreek row. Tribulus terrestris L. is what should stand in the bracket. The post on panel contradictions counted this among the four proofreading errors on the label, none of which touches an amount.

It is a fair question what that means for the gummy, and an honest answer has two halves. The likeliest explanation is a copied line that was not updated, in which case the extract is what the row says it is. But a label cannot prove that from its own artwork, and only laboratory identification of the plant material could settle it. The order desk on +1 (877) 257-0710 is the place to ask whether one exists. What this post does is take the plant the row names at its word and look at what the research says about it, because “tribulus terrestris benefits for men” is one of the most searched phrases in this whole aisle and the evidence behind it is odder than the reputation.

The study of twenty-one men

One of the papers that tested the testosterone claim head on is short and cheerfully small. In 2005 a Bulgarian group published a randomised trial with a title that gives the game away: “The aphrodisiac herb Tribulus terrestris does not influence the androgen production in young men.”

Twenty-one healthy men aged 20 to 36, with body weights running from 60 to 125 kg, were split into three groups of seven. One group took 20 mg of Tribulus terrestris extract per kilogram of body weight per day, one took 10 mg per kilogram, and one took placebo. The daily amount was divided into three intakes and continued for four weeks. Serum testosterone, androstenedione and luteinising hormone were measured the day before and at 24, 72, 240, 408 and 576 hours after starting.

Mean values as reported in the abstract. The authors report no significant difference between groups on any measure (p above 0.05), and all values were within the normal range.

The tribulus groups did not differ significantly from placebo on any measure, and on testosterone the placebo group’s mean was in fact the highest of the three. The authors concluded that the plant’s steroid saponins possess neither direct nor indirect androgen-increasing properties.

Fairness requires two caveats. Seven men to a group is a very small trial, and it could have missed a modest effect. And these were healthy young men whose testosterone was already in the normal range, who have little room to go up. Both points are real, and they are the reason that this single paper is not the last word. They are also the reason the paper is not simply dismissed, because every later trial of tribulus that measured testosterone has to be read against it.

What the later trials found

Three further trials show how the evidence spreads out once you leave healthy young men.

Sources: Santos 2014, Kamenov 2017 and Vilar Neto 2025.

The Brazilian pilot found nothing. The Bulgarian trial, which is the largest and best-resourced of the three, found something on the questionnaire and did not, in its abstract, report a testosterone result. The 2025 review then looked across ten studies of 15 to 172 men and found the same split: a low-quality signal on erectile function in some studies and no robust evidence of a testosterone rise. Its Jadad quality scoring rated half of the included studies as low methodological quality. Only two studies showed a rise in total testosterone within the treated group, the rises were small in clinical terms at 60 to 70 ng/dl, and both were in men with hypogonadism. The authors concluded that tribulus has a low level of evidence for erectile function in men with erectile dysfunction and that no robust evidence was found for increasing testosterone.

A 2026 meta-analysis of randomised trials in the International Journal of Impotence Research reached a matching conclusion from the other side. Tribulus outperformed placebo on the erectile function questionnaire, and total testosterone was not different between groups, and there was no difference in adverse events.

One more thing it does not do

A common assumption is that a herb with an aphrodisiac reputation must work like the prescription drugs for erectile dysfunction, by blocking the enzyme phosphodiesterase-5. It is worth knowing that a laboratory screen tested exactly that. The 2008 Milan study screened four traditional extracts, one of them Tribulus terrestris, against human recombinant PDE5A1, and found that only the horny goat weed extract and its compound icariin were active. Tribulus was not, in that assay.

That result does not say tribulus does nothing. It says that whatever it does is probably not through that enzyme, and it removes the easy explanation that many product pages quietly rely on. It does not explain the questionnaire results in the trials above either, and none of the abstracts cited on this page offers a settled mechanism, which is a fair summary of most of this shelf.

The arithmetic against this label

Everything above concerns amounts many thousands of times larger than the gummy carries. One milligram is a thousand micrograms, so the label’s 100 mcg is a tenth of a milligram.

Weight against weight. The Neychev figures are this desk’s arithmetic on the per-kilogram doses and the 60 to 125 kg body-weight range in the abstract. The 675 mg figure is six tablets at the 112.5 mg minimum stated per tablet.

The Kamenov row is the one to stop at. That trial used an extract concentrated 35 to 45 times and standardised to a named group of compounds, and the label’s row is a 10:1 extract that states no standardised content. Even if weights were matched, the material would not be the same material. The post on what a lot number proves explains why a ratio on a label is not something a code can verify.

A bottle of thirty gummies holds three milligrams of tribulus extract in total. The daily dose in the Brazilian pilot is what you would get from about 270 bottles.

Safety, and why it is not a footnote

The trials above report tribulus as well tolerated, and the 2026 meta-analysis found no difference in adverse events from placebo. That is a fair summary of monitored use at normal doses. It is not the whole record, and the rest deserves a place on the page.

• A 2010 case report in Nephrology Dialysis Transplantation describes a young man who took a herbal water made from the plant, to prevent kidney stones, for two days. He arrived with a seizure, very high liver enzymes and raised creatinine, and improved after stopping. The report attributes hepatotoxicity, nephrotoxicity and neurotoxicity to the plant extract. The amount and preparation were not standard and cannot be compared with a commercial product.
• A 2015 case report in Clinical Nephrology is titled “Acute kidney injury and hyperbilirubinemia in a young male after ingestion of Tribulus terrestris.” This desk can quote the title and no more, and cannot vouch for the product or the dose involved.

Two case reports are two case reports. They cannot establish how often such reactions happen or whether they happen at all at a supplement dose, and it would be wrong to present them as a warning about a gummy that carries a tenth of a milligram. They are a reminder of the thing the bottle’s own caution already says: a botanical is a pharmacologically active substance, and anybody with a known medical condition, and, given the case reports above, particularly anybody with kidney or liver disease, should speak to a physician before starting this or any supplement. The side effects page prints that caution in full.

A plain-English table of what can be said

A summary of the sources cited on this page. It is not medical advice.

What a buyer can do with this

• Do not buy this gummy for its tribulus. If tribulus is what you want, the trials used hundreds of milligrams of it, and even then the evidence is thin and mostly about a questionnaire.
• Do not expect a testosterone effect. Nothing on this page says one is likely at any dose, and there is no trial at this one.
• Ask about the plant. If the misprinted binomial bothers you, ask the order desk on +1 (877) 257-0710 whether a plant identity certificate exists for the tribulus extract, and treat the answer as information.
• Read the adulteration record before buying anything in this aisle. The post on the shelf with the worst record explains why the channel you buy through matters more than any single row.

The short verdict on the tribulus row

Tribulus is a herb whose reputation is bigger than its data. The testosterone claim does not survive contact with the trials that tested it, the erectile-function signal is modest and confined to gram-scale doses, and the safety picture is good in trials and complicated in case reports. On this panel the plant is honestly named, honestly weighed and carries the wrong Latin name in brackets. It is a signature row on a bottle whose real doses are elsewhere, and a reader who does the division will see that at once. The rest is a proofreading error, and the label is better for having it pointed out.

References