Epazote: Mexico’s Bean Herb, Its Pungent Oil and What It Takes to Use It Safely

Epazote’s name comes from two Nahuatl words meaning “skunk sweat,” a nod to the smell. This strong-smelling Mexican herb, Dysphania ambrosioides, is best known as the leaf that goes into a pot of beans. The same plant, called wormseed in English, has a long history as a remedy for intestinal worms. Its essential oil is rich in ascaridole, a compound that’s toxic in concentrated form and, in pure form, a shock-sensitive explosive.

At a glance

Flavor and the compounds behind it

Epazote’s smell is strong and hard to pin down. Gernot Katzer says it’s difficult to describe and that, to him, it smells like epazote.² Nikita Ephanov, in Tasting Table, compares the flavor to anise or licorice and calls it strong and eucalyptus-like, which is why it’s used sparingly.⁴ People often liken it to tarragon, fennel, mint and summer savory. That’s cooks’ shorthand, though. Epazote is more assertive than any of them.

The smell comes from an essential oil found in all the aboveground parts of the plant, about 0.7 percent in the leaves according to Katzer. Its signature compound is ascaridole, which Katzer reports at high levels in the oil (70 percent, with one source stating 86 percent). A 2025 review in Plants names ascaridole, p-cymene and α-terpinene as the key compounds.³ Katzer adds that the makeup varies by origin: plants grown in Europe or Asia taste much stronger, while oils from Latin American plants are richer in other monoterpenoids. Ascaridole itself has a pungent, not very pleasant flavor, and in pure form it’s a shock-sensitive explosive.²

Fresh or dried. Katzer says the dried herb is considered inferior to fresh, though in his view not as bad as most sources claim.² Tasting Table says dried epazote is less aromatic but easier to keep on hand.⁴

Origin and history

Kew gives the native range as the Americas and lists the plant as introduced across much of Africa, Europe and Asia, in Australia and New Zealand, and in many U.S. states.¹ Katzer puts its origin in Central and Southern Mexico and says it’s now a common introduced plant in the warmer parts of Europe and the United States.²

The name comes from Nahuatl, the language of the Aztecs. The U.S. Botanic Garden says it comes from two Nahuatl words meaning “skunk sweat,” a nod to the smell.⁵ The older genus name Chenopodium means “goose foot” in Greek, and the species name ambrosioides means “food of the gods.”

The English name wormseed comes from the plant’s use against intestinal worms. Katzer notes that the seeds are used mainly as a vermifuge.²

How epazote is used

• Beans. Bean dishes are its best-known use, Mexican refried beans above all, but also everything from black beans to spicy pintos.
• Yucatán and the Maya south. Epazote is tied to the Mayan cooking of southern Mexico. In a recipe for papadzules (pumpkin seed enchiladas) from a 2000 Yucatecan family cookbook, a bunch of epazote is boiled with tomatoes and habanero chiles, and the ground pumpkin seeds are then dissolved in that cooking water to make the sauce.⁶
• Other dishes. It goes into quesadillas, pozole, moles, bean-filled sopes and corn salad, and the fresh herb into soups, salads and meat dishes.

How much and when. Tasting Table suggests starting with a single leaf and adding it near the end of cooking, since heat fades the flavor.⁴ The Yucatecan recipe above simmers it from the start.⁶ Cooks do both. A sprig or two per pot of beans is a good place to start.

Cooks often say epazote makes beans less gassy. The U.S. Botanic Garden’s education sheet says it can stop gas from forming, and Katzer reports that this belief is why people use it with beans.⁵² We found no clinical study testing the claim.

Buying and quality

Fresh epazote can be hard to find. Slightly wilted fresh leaves are still fine to buy. We found no grading standard for epazote. The plant grows easily and spreads by seed, and the U.S. Botanic Garden warns it can turn into a garden weed.⁵

Storage

We found no published shelf life for fresh or dried epazote. Keep fresh sprigs in the fridge and use them within days, and keep dried leaf sealed, away from heat and light.

Safety and regulation

The oil is the hazard. TRAMIL, a Caribbean research program on traditional medicine, reports that a single oral dose of 5 ml of the essential oil has been reported to be lethal in adults, and that some poisonings have ended in death.⁷ It says oral use is contraindicated in people with liver disease and that the oil can be toxic, particularly in weak individuals.⁷ The U.S. Botanic Garden says large doses of epazote can be poisonous to animals and humans.⁵ A 2022 review links the toxicity of Dysphania oils to major components including ascaridole and reports dose-dependent toxicity in mice.⁸

The leaf is milder, but we didn’t find anyone who’s studied it in cooking. TRAMIL cites an oral study in mice of the aboveground parts that found no deaths or signs of toxicity, and concludes that the traditional infusion is safer than the essential oil.⁷ It also reports genotoxic and cytotoxic effects in cultured human cells at high extract concentrations.⁷ None of this measures the small amounts you’d use to season beans.

Pregnancy and children. TRAMIL advises against medicinal use during pregnancy, because it can cause miscarriage, and during breastfeeding or in children under 5.⁷ That guidance is for medicinal preparations, not seasoning, but it’s the only formal guidance we found.

Food regulation. Epazote isn’t on the FDA’s lists of spices and natural seasonings generally recognized as safe, of essential oils and natural extractives generally recognized as safe, or of approved natural flavoring substances.⁹¹⁰¹¹ We found no FDA or EU food regulation that names epazote either way, and no national limit for ascaridole in food.

Health claims. TRAMIL accepts the traditional oral use against roundworm, pinworm and hookworm, with the cautions above. That’s an assessment of traditional use, not a clinical trial.⁷ The 2022 review notes that most antibacterial work on these oils was done in vitro, and that there have been no human clinical trials of anticancer effects.⁸ Claims that epazote treats fever or osteoporosis have no traceable source, so we don’t repeat them.

Nutrition. TRAMIL gives these values per 100 g of leaves, from Duke and Atchley’s 1986 Handbook of Proximate Analysis Tables of Higher Plants: calcium 340 mg, phosphorus 52 mg, iron 5.2 mg, carotene 2,420 µg and ascorbic acid 11 mg.⁷

Substitutes and comparisons

• Epazote substitutes
• Mexican oregano and oregano; Katzer suggests a mix of savory, oregano and boldo leaves when fresh epazote is unavailable²
• Other Latin American herbs: culantro and cilantro