Last updated: · Published by Eternal Elixir
Fadogia agrestis is a West African shrub whose dried stem is sold across the United States as a testosterone-support supplement. It reached American shelves through podcasts and social media rather than through clinical research, and with this particular ingredient that distinction matters more than usual: every published study on this plant to date has been run in rats, in a test tube, or as a survey of traditional plant use. Not one has been run in people.
That does not make it useless. It does mean the marketing around it runs a long way ahead of the data, and the sensible way to approach it is to understand exactly what the rodent work found, what it did not test, and how to read a label so you know what you are actually swallowing.
Key takeaways
- Fadogia agrestis raised serum testosterone in male rats in a dose-dependent pattern; there are zero published human trials, so effects in men remain unmeasured.
- The popular 600 mg serving is a market convention, not a figure derived from the animal data — and it means nothing unless the label also states an extract ratio.
- The same extract that raised testosterone in rats also altered testicular, liver and kidney measures over longer dosing, with recovery mainly at the lowest dose tested.
- Eternal Elixir sells it in the United States as a labeled botanical blend with tongkat ali, third-party tested, 90 capsules per bottle.
What Is Fadogia Agrestis?
Fadogia agrestis is a shrub in the Rubiaceae family — the same botanical family as coffee — native to West Africa, particularly Nigeria and Burkina Faso. Traditional use centers on the stem, prepared as a water decoction, and the plant appears in ethnobotanical surveys of West African herbal markets alongside dozens of other regional species. Taxonomically it is now often listed as Vangueria agrestis, which is why some research papers on the plant do not carry the fadogia name at all.
What sells it in the US is a single mechanism claim: that the plant stimulates luteinizing hormone, which in turn signals the testes to produce more testosterone. That mechanism is plausible and is the one every product page repeats. It is worth knowing that the mechanism was inferred from a rodent hormone measurement, not demonstrated directly in men.
Commercially, it almost always appears in one of three forms: a raw stem powder, a concentrated extract standardized to a ratio such as 10:1, or a blend where it is paired with tongkat ali. If you are surveying the wider category first, our guide to how the major natural testosterone boosters compare on evidence and dose puts fadogia in context against ingredients with far more human research behind them. Readers who have worked through what is and is not known about turkesterone side effects will recognize the same pattern here: heavy social-media demand, thin clinical literature.
What the Fadogia Agrestis Research Actually Shows
A search of PubMed for “fadogia agrestis” in August 2026 returns ten indexed records. Four are phytochemistry papers isolating compounds from the plant. Two are ethnobotanical surveys of West African herbal medicine.
Two are rodent hormone and behavior studies. Two are rodent safety studies. Zero are human clinical trials. That distribution — not any single headline finding — is the most important fact about this ingredient.
The 2005 rat study everyone cites
The foundation of this entire market is one paper. Research published in the Asian Journal of Andrology dosed male albino rats orally with 18, 50 and 100 mg/kg body weight of an aqueous stem extract at 24-hour intervals, then measured sexual behavior parameters and serum testosterone on days 1, 3 and 5.
All three doses increased mount and intromission frequency and prolonged ejaculatory latency, and serum testosterone rose in a manner the authors described as suggestive of dose-dependence (Yakubu et al., 2005, PMID 16281088).
Read that carefully. It is a five-day rodent study with three dose groups.
It is genuine evidence of a hormonal effect in rats. It is not evidence of a benefit in a 35-year-old man taking capsules for eight weeks, and the paper never claimed to be.
What happened when the same extract ran for 28 days
The same research group extended the dosing. Published in the Journal of Ethnopharmacology, a 28-day study using identical doses of 18, 50 and 100 mg/kg found significant changes across testicular function indices — testicular cholesterol, sialic acid, glycogen and several enzyme activities all shifted relative to controls.
The authors concluded these alterations were indications of adverse effects on male rat testicular function, with recovery observed mainly at the lowest 18 mg/kg dose (Yakubu et al., 2008, PMID 18023305).
This is the study that rarely makes it onto a product page, and it is the reason the short-term testosterone result should not be read as a green light for indefinite high-dose use. The two papers come from the same lab, using the same extract, in the same animal model. They are a matched pair, and quoting only the first one is a choice.
Trying fadogia agrestis in the US? Eternal Elixir’s Tongkat Ali + Fadogia 2010mg Botanical Extract Blend ships fast across the United States with 90 capsules per bottle — twice the value of most competitors. Browse the longevity range →
The gap nobody advertises: zero human trials
Two further rodent papers round out the picture. A 2009 Human & Experimental Toxicology study examined the mode of cellular toxicity of the aqueous stem extract in male rat liver and kidney (PMID 19755438), and a 2023 Reproductive Sciences paper reported that the stem extract restored selected erectile-function biomolecules in paroxetine-treated Wistar rats (Ogunro and Yakubu, 2023, PMID 35969364).
Both are rat models. Twenty-one years after the first testosterone paper, the human column is still empty.
Fadogia Agrestis Dosage: Where the 600 mg Convention Came From
Walk through the US market and you will see 600 mg on bottle after bottle. It looks like a consensus clinical dose.
It is not. It is a market convention that hardened early and then propagated, and the arithmetic underneath it is worth seeing.
Doing the rat-to-human math honestly
Animal doses are not transferred to humans by weight. They are scaled by body surface area, using the standard pharmacology conversion in which the rat correction factor is 6 and the human factor is 37 — a divisor of roughly 6.2. Run the numbers on the published doses:
- 18 mg/kg in rats scales to roughly 2.9 mg/kg in humans — about 200 mg for a 70 kg adult.
- 50 mg/kg scales to roughly 8 mg/kg — about 565 mg.
- 100 mg/kg scales to roughly 16 mg/kg — about 1,130 mg.
So 600 mg sits near the human equivalent of the middle rat dose, not the lowest. The lowest dose — the one where the rats recovered their testicular measures — converts to roughly a third of what the average US bottle recommends. Nobody appears to have chosen 600 mg on the basis of that calculation; it is simply where the market landed.
Why “600 mg” without an extract ratio is meaningless
Here is the practical trap. The rat studies used an aqueous stem extract of unstated concentration.
A US bottle stating “600 mg” may mean 600 mg of raw milled stem powder or 600 mg of a 10:1 concentrate — nominally ten times the plant material. Those two products carry the same number on the front and are not remotely equivalent. An extract ratio is the only thing that makes a milligram figure interpretable.
| Format | What the label states | What it actually tells you | Best for |
|---|---|---|---|
| Raw stem powder | Milligrams of plant material | Directly comparable to traditional preparations, but weak per gram and often bulky | People who want to control the input themselves |
| Standardized extract (e.g. 10:1) | Milligrams plus a concentration ratio | Interpretable: 1,500 mg of a 10:1 extract represents 15 g of starting material | Anyone who wants to know what they are dosing |
| Botanical blend | Each ingredient listed with its own amount and ratio | Full picture only when every component is broken out, not hidden in a proprietary blend | Stacking fadogia with a better-studied partner ingredient |
Eternal Elixir takes the third route. The Tongkat Ali + Fadogia blend declares 1,500 mg of a 10:1 fadogia extract, 500 mg of a 200:1 tongkat ali extract and 10 mg of BioPerine per three-capsule serving, with nothing folded into a proprietary blend.
At $19.99 for 90 capsules and 30 label servings, that works out to roughly $0.67 per three-capsule serving.
Because the serving is three capsules rather than one, it is also straightforward to try a smaller amount first and scale from there — something a single-capsule format does not allow. Anyone comparing bulk powder economics against finished capsules will find the trade-offs laid out in our review of the BulkSupplements bulk-powder model.
Side Effects and Safety Signals Worth Taking Seriously
Fadogia agrestis has no long-term human safety record, because it has no human record at all. What exists is rodent toxicology, and it is not silent.
Liver and kidney findings
The 2009 cellular toxicity paper looked specifically at male rat liver and kidney tissue after aqueous stem extract administration. Combined with the 28-day testicular findings, the pattern across the rodent literature is that short exposure produced the hormonal effect people want while extended exposure produced organ-level changes the authors characterized as adverse. Whether that translates to humans at market doses is unknown — but “unknown” is a different word from “safe.”
Who should leave this one alone
Given the state of the evidence, it is not appropriate for anyone under 18, anyone pregnant or breastfeeding, anyone with existing liver or kidney concerns, or anyone taking prescription medication without first talking to their own clinician. Cycling — a period on, a period off — is the common user practice and is a reasonable hedge against the 28-day rodent finding, though it too is a convention rather than a tested protocol.
Fadogia Agrestis and Tongkat Ali: How the Two Differ
These two ingredients are constantly bundled together, and people reasonably assume they are interchangeable. They are not.
| Attribute | Fadogia agrestis | Tongkat ali (Eurycoma longifolia) |
|---|---|---|
| Origin | West African shrub, stem used | Southeast Asian tree, root used |
| Human trials | None published | Multiple published trials in men |
| Typical extract ratio | 10:1 | 100:1 to 200:1 |
| Proposed mechanism | Luteinizing hormone stimulation | Reduced binding of testosterone to carrier proteins |
| Safety record | Rodent toxicology signals over 28 days | Longer track record of human use |
| Best for | An optional addition once the basics are covered | A foundation ingredient in a men’s stack |
Best for, in one line each: tongkat ali is the defensible foundation; fadogia agrestis is the experimental addition. That is why Eternal Elixir sells both a single-ingredient Tongkat Ali 200:1 extract at $29.99 for 90 capsules — $1.00 per three-capsule serving — and the combined blend.
If you only want the ingredient with human data behind it, the standalone is the cleaner choice. Men building a broader routine often add shilajit, whose evidence base for men is meaningfully deeper — Eternal Elixir’s Shilajit 1000mg 20:1 extract with 20% fulvic acid is the in-house option — or look at what panax ginseng does for energy and drive.
How to Choose a Fadogia Supplement in the US
Four checks separate a defensible purchase from a guess:
- Demand an extract ratio. A milligram number with no ratio is not information. View the full supplement facts panel before buying, not the marketing copy.
- Reject proprietary blends. If fadogia is inside an unbroken blend total, you cannot know your dose and neither can anyone advising you.
- Check for third-party testing. This is a wild-harvested West African botanical with a genuine adulteration and heavy-metal risk profile. Every Eternal Elixir product is third-party tested for purity.
- Start below the label serving. The rodent dose with the cleanest recovery profile was the lowest one tested. A multi-capsule serving makes starting low easy.
Eternal Elixir ships across the United States with free shipping over $100, and both men’s-health formulas sit alongside the rest of the range if you are assembling a longevity stack rather than buying a single bottle.
Frequently Asked Questions
What does fadogia agrestis do to you?
In rats, an aqueous extract of fadogia agrestis stem raised serum testosterone and changed mating-behavior measures within five days. In people, nothing has been measured in a published trial, so the honest answer is that its effects in humans are unquantified. Users typically take it hoping for testosterone support, libido support, and training drive.
Does fadogia agrestis actually increase testosterone?
It raised testosterone in male rats in a dose-dependent pattern in the 2005 Asian Journal of Andrology study. That result has never been reproduced in a human trial. Anyone claiming a specific percentage increase in men is extrapolating from rodents, not reporting a measurement.
What are the best testosterone supplements for men?
The ingredients with the most human data behind them are the ones worth building a stack around first — tongkat ali, ashwagandha, zinc and vitamin D have run human trials that fadogia agrestis has not. Fadogia is better understood as an optional addition than as a foundation ingredient.
What is better, tongkat ali or fadogia agrestis?
Tongkat ali has the stronger evidence base: multiple human trials in men, a standardized extract market, and a longer safety record. Fadogia agrestis has rodent data only. If you are choosing one, tongkat ali is the more defensible pick; blends combine them because they are thought to act through different points in the same hormonal pathway.
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