Supplement analysis backed by scientific evidence · PT

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Limited evidenceMen's health

Fadogia Agrestis

A West African shrub that became a testosterone-booster trend on the strength of a single 2005 rat study — with zero human trials of any kind. A follow-up from the same laboratory found the same extract damaged rat liver and kidney at the doses that raised testosterone, which makes this one of the harder supplements on the market to justify.

What the science says

  • Raises testosterone Limited evidence

    The entire claim traces to one rodent experiment in which an aqueous stem extract at 18-100 mg/kg for five days raised serum testosterone in male rats several-fold and increased mounting behaviour. No human being has ever had testosterone measured in a controlled trial of Fadogia agrestis, so neither an effective dose nor whether any effect occurs in men is known.

  • Improves libido and erectile function Limited evidence

    Aphrodisiac effects have been reported in rats, including a paroxetine-induced erectile dysfunction model where the extract restored several testicular and penile biomarkers. Rodent mounting frequency is a weak proxy for human sexual function, and no clinical trial in men exists at any dose or duration.

  • Product quality is reliable Limited evidence

    Analytical work using UHPLC-MS on commercial Fadogia supplements found substantial variability in phenolic content between products, and the plant is easily confused with related Vangueria species in trade material. Supplements are typically labelled only as a "10:1 extract" with no marker compound standardised, so what is in the capsule is essentially unverifiable by the buyer.

Dosage & safety

Studied doseThere is no evidence-based human dose. Labels commonly specify 300-600 mg/day of a 10:1 stem extract, a figure with no trial basis. The rodent doses that raised testosterone (18-100 mg/kg) would scale to roughly 200-1100 mg/kg-equivalent in humans depending on the allometric assumption — but the same range is where organ toxicity appeared in rats, so scaling it up is exactly the wrong lesson to draw.
SafetyThis is the entry's main point. In a 28-day rat study from the same group that reported the testosterone effect, the aqueous stem extract at 18-100 mg/kg produced dose-dependent liver and kidney damage: elevated serum ALT, AST and ALP, altered organ weights, and evidence of membrane and cellular injury. No human toxicology, no chronic-use data, and no drug-interaction data exist. Fadogia agrestis has no history of authorised food use in the EU or UK and is not an approved novel food there; it is sold in the US as a dietary supplement without pre-market safety review. Anyone with existing liver or kidney disease, on hepatotoxic medication, or drinking regularly has a clear reason to avoid it. If a man's goal is higher testosterone, the tested routes are weight loss, sleep, treating hypogonadism medically, or a prescribed therapy — not an untested herb with published rodent hepatotoxicity. Anyone using it anyway should have liver enzymes checked.

Scientific references

Where to buy

Nutricost, Fadogia Agrestis, 600 mg, 240 Capsules

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