Supplement analysis backed by scientific evidence · PT

← All supplements
Limited evidenceGut health

Boldo

Boldo is a Chilean leaf used as a digestive and "liver" tea with no controlled human efficacy trials and documented cases of hepatotoxicity — the opposite of what it is sold to do. Its essential oil contains ascaridole, a genuine toxin.

What the science says

  • Protects and detoxifies the liver Limited evidence

    Boldine, boldo's main alkaloid, is a legitimate antioxidant that protects against carbon tetrachloride-induced liver injury in rodents, and that animal work is the entire basis for the claim. In humans the published record runs the other way: a well-documented case of acute hepatitis following boldo-containing herbal laxative use, with recovery on withdrawal and recurrence on rechallenge.

  • Stimulates bile flow and relieves dyspepsia Limited evidence

    Boldo increases bile secretion in animal models and is approved in some European monographs as a traditional remedy for mild dyspepsia and bloating, which is a use-based rather than evidence-based approval. No placebo-controlled trial has measured dyspepsia symptoms with boldo alone; the few positive human results come from multi-herb combinations that also contain artichoke or fumitory.

  • Dissolves gallstones Limited evidence

    There is no human evidence that boldo dissolves gallstones, and its choleretic action makes it potentially hazardous in gallstone disease — stimulating bile flow against an obstructed duct can precipitate biliary colic. Boldo is contraindicated, not indicated, in bile duct obstruction.

Dosage & safety

Studied doseTraditional and monograph doses are roughly 1-2 g of dried leaf as an infusion up to three times daily, or 0.1-0.5 mL of tincture. European monographs cap use at about 2-4 weeks and advise against the essential oil entirely. No dose has been validated by a controlled human trial.
SafetyThe essential oil contains ascaridole, a peroxide terpene that is hepatotoxic and neurotoxic; boldo essential oil should not be taken internally at all. Boldo leaf preparations have caused acute hepatitis, and boldo is contraindicated in liver disease, bile duct obstruction, gallstones, and severe liver impairment. It is an abortifacient in traditional use and is contraindicated in pregnancy and breastfeeding. Case reports and pharmacology indicate boldo potentiates warfarin and raises INR — avoid with anticoagulants. Do not combine with other hepatotoxic supplements or with alcohol, do not use continuously beyond a few weeks, and stop at any sign of jaundice or abdominal pain.

Scientific references

Where to buy

View on iHerb

Referral link — this site may earn a commission on purchases.

Related in Gut health