Testosterone & Hormonal
Tongkat Ali (Eurycoma Longifolia)
Also known as: Longjack · Malaysian ginseng · Pasak bumi · Eurycomanone
A Malaysian root with consistent human evidence for raising free testosterone by reducing SHBG. Also reduces cortisol, improving the testosterone-to-cortisol ratio relevant for training adaptations.
Effective Dose
200–400mg / day
per clinical evidence
Evidence Level
Moderate
Testosterone & Hormonal
Mechanism
Quassinoid SHBG reduction, StAR protein upregulation, HPA axis normalisation
primary action
Best For
Free testosterone
Libido, Stress, Male fertility
This profile is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications.
What Is Tongkat Ali (Eurycoma Longifolia)?
Tongkat ali (Eurycoma longifolia) root has been used in Southeast Asian traditional medicine for centuries as an aphrodisiac and tonic. Eurycomanone and other quassinoids are the primary actives, with human trials demonstrating increases in free testosterone (via SHBG reduction), improvements in sperm parameters, and reduction of stress-related cortisol.
How It Works: The Science
Tongkat ali quassinoids inhibit SHBG binding to testosterone, increasing the free fraction available to androgen receptors. They also stimulate StAR protein expression in Leydig cells (increasing testosterone synthesis) and modulate the HPA axis (reducing cortisol). The combined effect of more testosterone and less cortisol improves the anabolic-to-catabolic ratio.
Primary Mechanism
Quassinoid SHBG reduction, StAR protein upregulation, HPA axis normalisation
Evidence-Based Benefits
Dosage Guide
Effective Dose
200–400mg / day
200–400mg/day standardised to 22% eurycomanone (water-soluble 100:1 extract). Physta is a well-studied patented extract. Take in the morning — energising effect may interfere with sleep.
Safety Profile & Side Effects
Well tolerated. Mercury contamination has been found in some commercial products — choose products tested for heavy metals. Mild agitation or insomnia at high doses.
Who Should (and Shouldn't) Take It
Men experiencing age-related testosterone decline, high-stress athletes with elevated cortisol, men wanting natural fertility support. One of the strongest natural testosterone optimisers with human evidence.
Frequently Asked Questions
Related Ingredients
Medical Disclaimer
Ingredient profiles are for informational purposes only and do not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications. Full disclaimer →