Tongkat Ali
Also known as: Eurycoma longifolia, Malaysian Ginseng, Longjack, Physta
Effective Dosage
200 mg/day (standardized root water extract based on clinical trials)
What the Science Says
Tongkat Ali is a root extract from a Southeast Asian tree (Eurycoma longifolia) used for centuries as a traditional remedy. Clinical trials show it can modestly improve testosterone levels, erectile function, and immune markers in middle-aged men and women, especially when combined with exercise. At 200 mg/day of a standardized extract, benefits on sexual function and immunity appeared within 4–6 weeks in study participants.
What It Doesn't Do
Won't replace testosterone therapy for clinically diagnosed hypogonadism. Not proven to build muscle on its own. No solid human evidence it burns fat or boosts athletic performance. Don't expect dramatic hormone changes — effects in studies were modest. Not a cure for narcolepsy or serious sleep disorders. Animal data on sperm improvement doesn't automatically translate to humans.
Evidence-Based Benefits
In men with androgen deficiency of aging (ADAM), 200 mg/day combined with concurrent exercise training improved erectile function and total testosterone levels over 6 months, though the standalone supplement effect was not isolated (PMID: 33541567). A 4-week RCT in middle-aged Japanese adults found 200 mg/day of Physta® improved immune parameters including total T-cell counts and immunological vigor scores compared to placebo (PMID: 26816234). Animal studies suggest possible benefits for sleep consolidation and thermoregulation (PMIDs: 39055967, 36047106), and rat models showed protective effects on testicular function against chemotherapy-induced damage (PMID: 39369924).
Weak EvidenceEffective at: 200 mg/day (standardized water extract) based on clinical trials; animal studies used 400-800 mg/kg
Source: auto-research
Absorption & Bioavailability
Unknown — no pharmacokinetic studies were included in the provided papers. Standardized water extracts (e.g., Physta®) are the form used in clinical trials, suggesting this formulation may be important for consistent effects.
Red Flags to Watch For
- A case report documents new-onset atrial flutter (irregular heart rhythm) in a 71-year-old man after starting Tongkat Ali — cardiac patients should consult a doctor first
- A case report documents acute liver injury (jaundice, elevated liver enzymes) in a 47-year-old man after use — stop immediately if you notice yellowing of skin or eyes
- Commercial products vary widely in composition — metabolomics analysis found significant differences between branded products and authentic root extracts
- Most positive clinical evidence comes from studies using a specific branded extract (Physta®); generic products may not replicate these results
- Safety in people with heart conditions, liver disease, or those on medications has not been established in the provided studies
Products Containing Tongkat Ali
See how Tongkat Ali is used in these analyzed products:
LJ 100 Tongkat Ali by Double Wood Supplements
Supplement
Nugenix Tongkat Ali, Longjack, 200 mg, Capsules
Supplement
Innerbody Labs Testosterone Support
Supplement
Testo-Booster
Supplement
Focus Formula by Best Earth Naturals
Supplement
Research Sources
- PubMed
- NIH DSLD
This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Last updated: 2026-04-06