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Tka6.0
Tongkat Ali Research
Too few graded studies
17 peer-reviewed studies
What the evidence says
Too few graded studies
Tongkat Ali doesn't have enough studies with structured effect-size data yet to pool a verdict. Browse the studies below for individual findings.
Most evidence is from high-quality meta-analyses and randomised trials published 2010–2024 with a typical study size of 76 participants.
Based on 17 studies · 1 meta-analysis · 5 RCTs · 458 total participants
Confidence
Moderate confidence
What the studies found
0helped1unclear· 16 more without graded effect data
By outcome
Men's vitalityRaised total testosterone in ageing and hypogonadal men. Free testosterone did not differ from placebo in the largest RCT · 2-4 weeks · Cortisol fell within the 200 mg/day group in one RCT and was 16% lower than placebo in a 4-week trial. SHBG did not change · 4-8 weeks
6 studies in the last 5 years · Latest meta-analysis: 2015
201020172024
1Traditional Chinese medicine properties analysisReview2024
In plain English: Tongkat Ali has the main functions of tonifying kidney and replenishing essence, invigorating spleen and replenishing Qi, and soothing liver and relieving depression.
Ye DN et al. · Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica (2024)
Narrative literature review assigning traditional Chinese medicine properties to Tongkat Ali. It reports no search method and tests no outcome.
Tongkat Ali has the main functions of tonifying kidney and replenishing essence, invigorating spleen and replenishing Qi, and soothing liver and relieving depression.
The recommended dosage and usage of this medicine are 2-10 g daily and decoction with water, respectively. This is a TCM decoction dose of the herb, not a dose of standardized extract.
2Erectile function (IIEF-5 score)Meta-AnalysisCited 24×n=139 · medium study2015
In plain English: No significance between group difference was found in the mean WMD of the change in the 5- item version of the international index of erectile function (IIEF-5) at week-12 (0.91; 95% CI: -1.50 to 3.33 with I(2)=89.5%, P-value=0.002) with statistical heterogeneity.
Kotirum S et al. · Complementary therapies in medicine (2015)
No clear effect
← WorseNo effectBetter →
Of the 342 articles identified, 2 studies involving a total of 139 participants were analyzed.
No significance between group difference was found in the mean WMD of the change in the 5- item version of the international index of erectile function (IIEF-5) at week-12 (0.91; 95% CI: -1.50 to 3.33 with I(2)=89.5%, P-value=0.002) with statistical heterogeneity.
Based on the subgroup analysis, significant improved IIEF-5 score of 2.15 (95% CI 1.03-3.27) was found in subjects with lower baseline IIEF-5 score, but this was not seen among those with higher baseline IIEF-5 score.
3Traditional uses, chemistry, pharmacology and toxicologyReviewCited 106×2016
In plain English: Liver and renal function tests showed no adverse changes at normal daily dose and chronic use of E. longifolia.
Rehman SU et al. · Molecules (2016)
The plant is reported to be rich in various classes of bioactive compounds such as quassinoids, canthin-6-one alkaloids and β-carboline alkaloids, with quassinoids accounting for a major portion of the root phytochemicals.
An acute toxicity study found the oral LD50 of the alcoholic extract in mice is between 1500-2000 mg/kg, while the aqueous extract LD50 is more than 3000 mg/kg.
Liver and renal function tests showed no adverse changes at normal daily dose and chronic use of E. longifolia.
4Safety and efficacy evaluationSystematic ReviewCited 7×2013
In plain English: An evidence-based systematic review of tongkat ali (Eurycoma longifolia) by the Natural Standard Research Collaboration, consolidating safety and efficacy data using a validated, reproducible grading rationale.
Ulbricht C et al. · Journal of dietary supplements (2013)
An evidence-based systematic review of tongkat ali (Eurycoma longifolia) by the Natural Standard Research Collaboration consolidates the safety and efficacy data available in the scientific literature using a validated, reproducible grading rationale.
This article includes written and statistical analysis of clinical trials, plus a compilation of expert opinion, folkloric precedent, history, pharmacology, kinetics/dynamics, interactions, adverse effects, toxicology, and dosing.
The abstract describes the review's scope only and reports no results.
In plain English: Therefore, TA might be a safe alternative to TRT.
George A et al. · Andrologia (2014)
The testosterone deficiency syndrome (TDS) is characterised by numerous symptoms, including low libido, increased fat mass, fatigue, erectile dysfunction or osteoporosis, and up to 80% of men will experience some kind of ageing males' symptoms.
This is caused by the age-depending decline in serum testosterone levels with concentrations being about 40-50% lower in men older than 60 years compared with young men.
The review describes Tongkat Ali as a natural alternative to testosterone replacement therapy that restores serum testosterone. It is a narrative review that reports no head-to-head trial against testosterone therapy, so it does not show Tongkat Ali can replace a prescribed treatment.
In plain English: Our investigation revealed that human studies evaluating the efficacy of ED-S ingredients are limited and have yielded no definitive findings of the effects on ED.
Balasubramanian A et al. · The journal of sexual medicine (2019)
Analysis of the top 6 erectile dysfunction supplements on Amazon.com plus a literature review of their 21 ingredients. Ginseng, horny goat weed, L-arginine, and tongkat ali were the most popular ingredients included in the analyzed products.
Our literature review identified 413 studies involving the 21 identified ingredients, of which 59 (16%) involved human subjects.
Among these 69 human studies, only 12 (17%) investigated supplement ingredients individually and reported improvement in ED.
In plain English: There was a significant increase in the total testosterone levels at week 12 (P < 0.05) in the Physta® 100 mg group and at weeks 4 (P < 0.05), 8 (P < 0.01) and 12 (P < 0.001) in the Physta® 200 mg group compared to placebo.
Chinnappan SM et al. · Food & Nutrition Research (2021)
105 men aged 50-70 with testosterone <300 ng/dL took Physta 100 mg, 200 mg or placebo daily for 12 weeks.
Significant increase in total testosterone at week 12 (Physta 100 mg) and at weeks 4, 8 and 12 (Physta 200 mg) versus placebo.
No significant between-group differences in free testosterone levels were observed, only within-group increases.
10Ethnobotany and pharmacological propertiesReviewCited 116×2010
In plain English: The plant parts are rich in various bioactive compounds (like eurycomaoside, eurycolactone, eurycomalactone, eurycomanone, and pasakbumin-B) among which the alkaloids and quassinoids form a major p...
Bhat R et al. · Fitoterapia (2010)
The plant parts are rich in various bioactive compounds (like eurycomaoside, eurycolactone, eurycomalactone, eurycomanone, and pasakbumin-B) among which the alkaloids and quassinoids form a major portion.
Even though toxicity and safety evaluation studies have been pursued, still a major gap exists in providing scientific base for commercial utilization and clearance of the Tongkat Ali products with regard to consumer's safety.
The present review aims at reviewing the research works undertaken till date, on this plant in order to provide sufficient baseline information for future works and for commercial exploitation.
15Sperm quality and pregnancy rateOpen-LabelCited 45×n=75 · small study2010
In plain English: The proprietary extract of Eurycoma longifolia Jack significantly improved the sperm quality in these patients, allowing for 11 (14.7%) spontaneous pregnancies.
Tambi MI et al. · Asian Journal of Andrology (2010)
Follow-up semen analyses showed significant improvement in all semen parameters (semen volume, sperm concentration, normal morphology, and motility).
350 men with idiopathic infertility received 200 mg/day of the standardized extract; 75 completed one full 3-month cycle.
Treatment allowed for 11 (14.7%) spontaneous pregnancies.
16Testosterone levels and symptomsOpen-LabelCited 57×n=76 · small study2012
In plain English: Results show that treatment of LOH patients with this Tongkat ali extract significantly (P < 0.0001) improved the AMS score as well as the serum testosterone concentration.
Tambi MI et al. · Andrologia (2012)
76 of 320 patients with late-onset hypogonadism took 200 mg/day of a standardised water-soluble extract for 1 month, with no control group.
Patients with normal testosterone rose from 35.5% to 90.8%, and those without AMS complaints from 10.5% to 71.7%.
The abstract reports no safety or adverse-event data.
In plain English: These results indicate that daily supplementation with tongkat ali root extract improves stress hormone profile and certain mood state parameters.
Talbott SM et al. · Journal of the International Society of Sports Nutrition (2013)
63 moderately stressed adults (32 men, 31 women) took a standardized hot-water extract of TA root or placebo for 4 weeks. The abstract does not say allocation was randomised.
Significant improvements were found in the TA group for Tension (-11%), Anger (-12%), and Confusion (-15%).
Salivary cortisol exposure fell 16% and testosterone status rose 37%.