Caltrops
Also known as: Caltrop, puncture vine, goathead, Tribulus terrestris
Overview
Tribulus terrestris (TT) is a plant traditionally used for various medicinal purposes, including enhancing sexual health, supporting cardiovascular function, and providing anti-inflammatory effects. It is a common ingredient in dietary supplements marketed to boost testosterone levels, improve sexual function, and enhance athletic performance. The plant's purported active compounds are steroidal saponins. Despite its traditional use and widespread marketing, scientific evidence supporting these claims remains limited and largely inconclusive. Current research does not robustly confirm the efficacy of TT for its claimed benefits. While generally considered safe for short-term use at moderate doses, there are reports of adverse effects, particularly with higher doses or prolonged use, necessitating caution.
Benefits
Scientific evidence for the benefits of Tribulus terrestris (TT) is limited and often inconclusive. A systematic review found insufficient evidence that TT supplementation significantly improves erectile dysfunction or serum testosterone levels in men, indicating a lack of strong support for its most common marketed uses. Some studies suggest potential benefits for lipid profiles, showing reductions in total cholesterol and LDL cholesterol, and increases in HDL cholesterol in physically active adults. However, effects on triglycerides and inflammatory markers are inconsistent. Limited evidence points to moderate beneficial effects on some inflammatory biomarkers (e.g., IL-6, hs-CRP), but these findings are mixed and not statistically robust. There is no clear evidence to support benefits of TT on muscle damage markers or athletic performance enhancement.
How it works
The proposed mechanism of action for Tribulus terrestris (TT) primarily involves its bioactive components, particularly steroidal saponins. These compounds are hypothesized to influence androgen receptors and modulate hormone levels, although human data do not strongly support this mechanism. Any observed effects on lipid metabolism and inflammation may be attributed to the antioxidant and anti-inflammatory properties of the plant's constituents, though the precise molecular targets remain unclear. The bioavailability and pharmacokinetics of TT compounds in humans are not well characterized, making it difficult to fully understand how it interacts with the body's systems.
Side effects
Tribulus terrestris (TT) appears relatively safe for short-term use (up to 3 months) at moderate doses, with mild side effects such as stomach cramps and nausea reported in some individuals. However, higher doses, typically exceeding 1000 mg/day, have been associated with more pronounced adverse effects including sleep disturbances, fatigue, and elevated heart rate. Rare but serious adverse events, such as liver and kidney damage, have been reported in isolated cases, warranting significant caution, especially for individuals with pre-existing medical conditions affecting these organs. While some controlled studies have not observed significant toxicity or changes in renal biomarkers, the overall safety data are limited. Due to insufficient research, drug interactions and contraindications are not well documented, and individuals on medication or with chronic health issues should consult a healthcare professional before use.
Dosage
There is no scientific consensus on the minimum effective or optimal dosage for Tribulus terrestris (TT) due to insufficient robust evidence. Typical supplement doses found in commercial products range widely, often between 250 mg to 1500 mg daily of TT extract, which is usually standardized to its saponin content. However, these dosages lack strong clinical validation. The timing of administration and specific formulation factors (e.g., type of extract, presence of cofactors) are also not well studied or established. Given the potential for adverse effects at higher doses, it is advisable to start with the lowest effective dose and monitor for any reactions. Due to limited research, specific upper limits and safety thresholds are not definitively established.
FAQs
Does TT boost testosterone?
Current scientific evidence does not support significant increases in testosterone levels in men following Tribulus terrestris supplementation.
Is TT effective for erectile dysfunction?
Clinical trials have shown no consistent benefit of Tribulus terrestris for improving erectile dysfunction.
Is TT safe?
Tribulus terrestris is generally considered safe for short-term use at moderate doses, but higher doses or prolonged use may pose risks, including potential liver or kidney damage.
How long before effects appear?
Due to a lack of consistent efficacy data, there is no clear timeline established for when effects of Tribulus terrestris might appear.
Research Sources
- https://pmc.ncbi.nlm.nih.gov/articles/PMC9368143/ – This systematic review of 7 randomized controlled trials (RCTs) found that Tribulus terrestris improved lipid profiles (decreasing total and LDL cholesterol, increasing HDL cholesterol) and showed moderate effects on inflammation. However, it reported no significant effect on muscle damage markers or hormone levels, and no toxicity. The study quality was moderate due to a small number of studies and heterogeneity.
- https://pubmed.ncbi.nlm.nih.gov/40219032/ – This systematic review of clinical trials specifically focused on men with erectile dysfunction. It concluded that there was no significant improvement in erectile function or testosterone levels with Tribulus terrestris supplementation. The review was considered high quality, but noted variability in study designs and dosages.
- https://www.opss.org/article/tribulus-terrestris-ingredient-dietary-supplements – This narrative review and collection of case reports assessed the safety profile of Tribulus terrestris. It indicated that the supplement is generally safe at moderate doses for short-term use (up to 3 months), but highlighted adverse effects at higher doses and rare cases of liver and kidney damage. The review noted limitations due to a reliance on case reports rather than controlled safety trials.
