Lj100
Also known as: Eurycoma longifolia Jack, Tongkat Ali, Longjack, Malaysian ginseng, LJ100, Eurycoma longifolia
Overview
Eurycoma longifolia, commonly known as Tongkat Ali or Longjack, is a herbal extract derived from the roots of the Eurycoma longifolia tree, native to Southeast Asia. It is primarily used as a natural supplement to enhance male sexual health, increase testosterone levels, improve athletic performance, and support male fertility. The extract LJ100 is a standardized form of Tongkat Ali root extract. Research on Tongkat Ali includes several randomized controlled trials (RCTs) and systematic reviews/meta-analyses, focusing on its effects on serum testosterone levels in men. The quality and consistency of evidence vary, and some studies report conflicting results. It is available in various forms, including capsules, powders, and extracts, with standardized extracts like LJ100 ensuring consistent potency. The active compounds, such as quassinoids and eurycomanone, are believed to contribute to its effects.
Benefits
Tongkat Ali supplementation has been shown to increase serum total testosterone levels, especially in men with low baseline testosterone (<300 ng/dL, hypogonadal men). A 2022 systematic review and meta-analysis including 9 studies and 232 participants found a significant increase in testosterone with a large effect size at doses ranging from 100 to 600 mg daily over 2 weeks to 12 weeks, with some studies extending to 6 months. The testosterone-boosting effect is more pronounced and statistically significant in hypogonadal men, while men with normal baseline testosterone levels show minimal or no significant increase. Some evidence suggests potential benefits for male fertility, muscle strength, and athletic endurance, but these claims have lower quality evidence and require further research.
How it works
Tongkat Ali is believed to act primarily by stimulating endogenous testosterone production, possibly through modulation of the hypothalamic-pituitary-gonadal axis. It may reduce the conversion of testosterone to estrogen and improve free testosterone availability. The bioactive compounds such as quassinoids and eurycomanone are thought to contribute to these effects. Absorption and bioavailability details are not fully elucidated, but oral supplementation at standardized doses is effective in raising serum testosterone in clinical trials.
Side effects
Tongkat Ali is generally well tolerated in doses up to 600 mg daily for short to medium durations (up to 6 months). Mild gastrointestinal discomfort, headache, and restlessness have been occasionally reported but are not common. No serious adverse events have been consistently reported in well-conducted trials. Due to limited data, caution is advised in patients on hormone-sensitive therapies or with hormone-related cancers. Safety in women, children, and pregnant or breastfeeding women is not established. It is important to consult with a healthcare professional before starting Tongkat Ali supplementation, especially if you have pre-existing medical conditions or are taking other medications.
Dosage
The minimum effective dose is approximately 100 mg/day of standardized extract (LJ100). An optimal dose range is 100–200 mg/day for 12 weeks, which appears effective for increasing testosterone in hypogonadal men. The maximum safe dose is up to 600 mg/day, which has been used safely in short-term studies (2 weeks to 6 months). It should be administered daily via oral administration; no specific timing relative to meals has been established. A standardized root extract (e.g., LJ100) is recommended for consistency. No specific cofactors are required; bioavailability appears adequate with oral dosing.
FAQs
Is Tongkat Ali effective for increasing testosterone?
Yes, particularly in men with low baseline testosterone, with clinically meaningful increases observed in multiple RCTs and meta-analyses.
How long does it take to see results?
Effects on testosterone have been observed as early as 2 weeks, with more consistent results at 12 weeks or longer.
Are there risks of hormonal imbalance?
No significant adverse hormonal effects reported in clinical trials, but long-term safety data are limited.
Can Tongkat Ali improve athletic performance?
Evidence is limited and less robust; benefits for muscle strength and endurance are possible but not conclusively proven.
Research Sources
- https://pmc.ncbi.nlm.nih.gov/articles/PMC9415500/ – This systematic review and meta-analysis included 9 clinical trials with 232 participants, focusing on Tongkat Ali’s effect on serum testosterone. It found significant testosterone increases in hypogonadal men (<300 ng/dL) with doses of 100–600 mg/day over 2–12 weeks, noting some publication bias but overall supporting Tongkat Ali’s efficacy for testosterone enhancement. The study's limitations included small sample sizes in individual studies and heterogeneity in dosing and duration.
- https://examine.com/supplements/tongkat-ali/ – This summary of a 2022 meta-analysis confirmed significant testosterone increases with Tongkat Ali supplementation, especially in men with low baseline levels. It highlighted variability in study quality and some studies showing no effect, emphasizing the need for more rigorous trials. Effect sizes were large in hypogonadal men but not significant in men with normal testosterone.
- https://magistralbr.caldic.com/storage/product-files/445511096.pdf – This evidence-based systematic review concluded that clinical data supporting Tongkat Ali’s benefits are promising but still limited. It graded evidence for testosterone enhancement as moderate (Grade C), indicating more high-quality RCTs are needed. The review also noted potential benefits for fertility and muscle strength but with low-quality evidence.
- https://www.medicalnewstoday.com/articles/tongkat-ali – This article provides an overview of Tongkat Ali, discussing its potential benefits, side effects, and dosage. It highlights the traditional use of Tongkat Ali for enhancing male sexual health and increasing testosterone levels, while also noting the need for further research to confirm these effects.
- https://www.healthline.com/nutrition/tongkat-ali-longjack-review – This review provides a comprehensive overview of Tongkat Ali, covering its potential benefits, side effects, and dosage recommendations. It discusses the evidence supporting its use for increasing testosterone levels, improving fertility, and reducing stress, while also highlighting the importance of consulting with a healthcare professional before using it.
