Tongkat Ali & Fadogia Agrestis: The Ultimate Stack Guide (2026)

By Blue Power Research Team  ·  2 June 2026  ·  10 min read

The tongkat ali and fadogia agrestis stack became one of the most talked-about supplement combinations after neuroscientist Andrew Huberman discussed it on his podcast in 2022. His personal claim — that this combination raised his testosterone from roughly 600 to the high 700s ng/dL — sent sales of both supplements soaring across the UK and US.

But here’s what most articles won’t tell you: the evidence behind these two ingredients is dramatically unequal. Tongkat ali (Eurycoma longifolia) has over 11 human clinical trials, a 2022 meta-analysis of 5 RCTs showing a statistically significant testosterone increase (SMD = 1.352, p = 0.001), and decades of traditional use across Southeast Asia. Fadogia agrestis has zero human clinical trials — only rat studies from a single research group, including one that found testicular toxicity at higher doses (Yakubu et al., 2008).

This guide separates what we know from what we’re guessing at. We’ll cover the clinical evidence for each compound, the real dosages from studies, safety concerns, and how to build a testosterone-supporting stack based on evidence rather than podcast hype.

What Is the Tongkat Ali and Fadogia Agrestis Stack?

The “stack” refers to taking tongkat ali and fadogia agrestis together, typically for testosterone support. The rationale — as popularised by Huberman — is that each compound works through a different mechanism:

• Tongkat ali may reduce sex hormone-binding globulin (SHBG), freeing more bound testosterone for use by the body, and modulate cortisol via the HPA axis
• Fadogia agrestis is proposed to increase luteinising hormone (LH), which signals Leydig cells in the testes to produce more testosterone

In theory, this creates a dual-pathway approach: more production (via LH stimulation) plus more bioavailability (via SHBG reduction). The problem? Only the tongkat ali half of this equation has human clinical data behind it. The fadogia mechanism is extrapolated entirely from rat studies.

Tongkat Ali: What Does the Clinical Evidence Show?

Tongkat ali (Eurycoma longifolia) is a flowering plant native to Malaysia, Indonesia, and Thailand. It has been used in traditional Southeast Asian medicine for centuries. Unlike most herbal supplements, it has a growing body of clinical evidence — including randomised controlled trials and a formal meta-analysis.

The 2022 Meta-Analysis Strongest Evidence

The most comprehensive analysis to date reviewed 9 studies (including 5 RCTs) on tongkat ali and testosterone. The pooled meta-analysis found a statistically significant increase in total testosterone with a standardised mean difference (SMD) of 1.352 (95% CI: 0.565–2.138, p = 0.001). This is classified as a “large” effect size in clinical research (Leisegang et al., Medicina, 2022).

Key Human Studies

Talbott et al. (2013) — A randomised, double-blind, placebo-controlled trial of 63 moderately stressed adults given 200 mg/day standardised hot-water extract for 4 weeks. Cortisol was reduced by 16% and measured testosterone was associated with a 37% change, with mood state scores also improving significantly (tension −11%, anger −12%, confusion −15%) (Talbott et al., JISSN, 2013). This trial finding cannot be transferred to Blue Power as a label claim. Blue Power's Tongkat Ali dose is 50 mg, which is below the typical trial dose range of 200–400 mg/day.

Tambi et al. (2012) — 76 men diagnosed with late-onset hypogonadism (LOH) received 200mg/day for one month. The proportion of men with normal testosterone rose from 35.5% to 90.8% (p<0.0001). Symptom improvement on the Aging Males’ Symptoms (AMS) scale went from 10.5% to 71.7% (Tambi et al., Andrologia, 2012). Important limitation: this was an open-label study without a placebo control.

Henkel et al. (2014) — A pilot study of 25 senior athletes aged 57–72, given 400mg/day for 5 weeks, found significant increases in both total and free testosterone plus improved muscular strength (Henkel et al., 2014).

Fadogia Agrestis: What Does the Evidence Show?

Fadogia agrestis is a shrub native to Nigeria, used in traditional West African medicine as an aphrodisiac. It gained mainstream attention almost entirely through Andrew Huberman’s podcast recommendations. Here is the honest picture:

The Evidence: Rat Studies Only

As of 2026, there are no published human clinical trials for fadogia agrestis. The entire evidence base comes from animal studies by a single Nigerian research group (Yakubu et al.):

Yakubu et al. (2005) — Male albino rats given fadogia agrestis at 18, 50, and 100 mg/kg body weight for 5 days showed dose-dependent increases in serum testosterone (p<0.05), increased mount frequency, and prolonged ejaculatory latency (Yakubu et al., Asian Journal of Andrology, 2005).

Why the 600mg Fadogia Dose Is Guesswork

The 600mg dose commonly recommended in supplement stacks and by Huberman is not derived from any human pharmacokinetic study. The rat studies used 18–100 mg/kg body weight. Simple allometric scaling from 18 mg/kg in rats yields roughly 200mg for a 70kg man — but this conversion is not validated by human data. The 600mg figure appears to be a rough extrapolation that has been repeated so often it sounds authoritative. It is not.

Should You Take Tongkat Ali and Fadogia Agrestis Together?

Short answer: Tongkat ali has legitimate clinical evidence supporting its use for testosterone support. Fadogia agrestis does not. Combining them means pairing an evidence-backed ingredient with an untested one that carries genuine safety concerns.

Tongkat Ali Dosage: What the Studies Used

Clinical trials have consistently used standardised hot-water extract of Eurycoma longifolia:

• 200mg/day: The most commonly studied dose. Used in the Talbott 2013 RCT (cortisol −16%; measured testosterone associated with a 37% change) and the Tambi 2012 LOH study (90.8% normalisation). Recommended as a general starting dose. This trial finding cannot be transferred to Blue Power as a label claim. Blue Power's Tongkat Ali dose is 50 mg, which is below the typical trial dose range of 200–400 mg/day.
• 400mg/day: Used in the Henkel 2014 pilot study of senior athletes (aged 57–72). Produced significant testosterone and strength improvements. This is the dose Huberman reportedly uses daily.
• 50mg in a multi-ingredient formula: When tongkat ali is combined with synergistic compounds — zinc, shilajit, L-arginine, maca root extract — a supportive dose contributes to the overall formula alongside the other ingredients targeting complementary pathways.

Study Quality and Funding Transparency

Safety: Side Effects and Who Should Avoid This Stack

Tongkat Ali Safety Profile

Tongkat ali is generally well-tolerated across clinical trials lasting 4–12 weeks. A 2017 systematic review of 11 human clinical trials reported no significant adverse events (Thu et al., 2017). Minor side effects reported include mild insomnia, restlessness, and increased body heat — likely related to stimulatory effects. Taking tongkat ali earlier in the day may reduce any sleep-related effects.

Fadogia Agrestis Safety Concerns

The safety picture for fadogia is genuinely concerning. The only extended-use study (Yakubu 2008) found testicular biochemical changes at every dose tested after 28 days. At the two higher doses (50 and 100 mg/kg), damage persisted even after a 10-day washout period. This is animal data and may not translate directly to humans — but it is all the data available, and it warrants serious caution.

A Better Approach: Evidence-Based Testosterone Support

Rather than pairing a proven ingredient with an unproven one, consider building your stack entirely from compounds with human clinical evidence. Tongkat ali works best alongside:

• Zinc: EFSA-approved claim (EU Regulation 432/2012) — “Zinc contributes to the maintenance of normal testosterone levels in the blood.” Direct regulatory backing, not just observational data.
• Shilajit: In a 90-day double-blind RCT, purified shilajit (250 mg twice daily) was associated with a 20.45% change in measured total testosterone in men aged 45–55 (Pandit et al., 2016, n=75). This trial finding cannot be transferred to Blue Power as a label claim. The trial used 250 mg purified shilajit twice daily (500 mg/day), a higher dose than the amount in the Blue Power formula. Works through a different mechanism (mitochondrial support and mineral transport) to tongkat ali.
• L-Arginine: The direct precursor to nitric oxide, supporting blood flow. Synergistic with zinc and shilajit for overall daily wellbeing for men.
• Korean Ginseng (Panax ginseng): Multiple RCTs support its role in energy, cognitive function, and male sexual health.

This is the approach behind formulas that combine multiple evidence-backed compounds rather than relying on untested single-ingredient protocols. For a broader view of what works for men over 40, see our guide to the best supplements for men over 40.

Frequently Asked Questions

The Bottom Line

Tongkat ali is one of the most well-evidenced herbal compounds in the men's nutrition literature. The 2022 meta-analysis, multiple RCTs, and a consistent safety profile across 11+ human trials make it a credible choice for men over 40 looking for nutritional support as part of a balanced diet.

Fadogia agrestis is a different story. Zero human trials, testicular toxicity concerns from the only extended animal study, and a dosage protocol based on extrapolation rather than evidence. The popularity of this compound is almost entirely driven by one podcast recommendation, not by clinical data.

If you want to build an evidence-based testosterone support stack, start with tongkat ali — and pair it with compounds that have their own human clinical evidence: zinc, shilajit, and L-arginine. That’s a stack built on science, not hype.