Educational information, not medical advice — ask your doctor or midwife.
Marañón, also called cajú or cashew, is the tree Anacardium occidentale. It gives two foods. One is the cashew nut; the other is the cashew apple, the soft juicy stalk the nut hangs from.
In Latin America the apple is pressed into a sweet, tart juice. Folk healers also brewed the leaves and bark as teas. The caustic oil inside the nut shell was dabbed on warts and corns.
Here is the honest verdict. Cashew nuts are a well-studied food with small, mixed effects on blood fats and blood pressure. The leaf, bark and shell uses rest on tradition and laboratory work, not on human trials.
Long traditional use shows that people valued this tree. It does not prove the plant works as a medicine, and it does not prove it is safe. Cashew is also one of the most common causes of severe nut allergy.
Different parts of the tree are claimed to work in different ways, and the evidence behind each is very different.
The nut is rich in unsaturated fat, fibre and plant sterols. Diets high in nuts lower LDL ("bad") cholesterol a little in human trials. Trials of cashews on their own show smaller and less steady results.
Cashew apple juice is high in vitamin C. Vitamin C prevents and treats scurvy; that is settled. It is not a treatment for colds, despite the folk claim.
Leaf and bark contain tannins, which bind proteins and taste drying. In test tubes and in animals, these extracts slow some gut bacteria and lower blood sugar. Whether that happens in people has not been shown.
The nut shell liquid holds anacardic acid and cardol. In lab dishes these kill bacteria and fungi. They are also caustic and blister skin, so this is a hazard rather than a home remedy.
Most people meet marañón as food, not as a supplement.
- Roasted cashew nuts, salted or plain. - Cashew butter, cashew milk and cashew-based creams. - Fresh or bottled cashew apple juice; cajuína in Brazil.
- Jams, sweets, wine and vinegar made from the apple. - Dried leaf or bark, sold loose for tea in Latin American markets. - Leaf or bark capsules and tinctures, sold as supplements.
- Cashew nut shell liquid, an industrial material used in brake pads and resins.
Nuts labelled "raw" in shops have still been steamed. Shell liquid is not a food or a home remedy, and reputable sellers do not offer it as one.
The tree is native to north-east Brazil. Tupi peoples ate the apple and used the name acajú, which became cajú and then cashew.
Portuguese traders carried it to Africa and India in the 1500s. From there it spread across the tropics and became a major crop.
Across Latin America and the Caribbean, folk healers used bark and leaf decoctions for diarrhoea and as mouth rinses for sore gums. The juice was given for colds, sore throats and for the bleeding gums of scurvy. Shell oil was painted on warts, corns and hard skin.
These were household and healer practices recorded by travellers and later by ethnobotanists. They are described here as history, not as instructions to copy.
Call your emergency number at once if, after eating cashew, you get swelling of the lips, tongue or throat, trouble breathing, widespread hives, vomiting with faintness, or a sudden drop in alertness. These are signs of a severe allergic reaction.
See a doctor the same day for a spreading, blistering rash after skin contact with shell oil or shell fragments.
Stop and see your doctor if a leaf or bark tea brings stomach pain, dark urine, yellow skin or eyes, or repeated low blood sugar episodes.
See a doctor for diarrhoea with blood or fever, or diarrhoea lasting more than two days. Do not treat it with bark tea.
Cashew nuts and cashew apple products are ordinary foods in the United States, the United Kingdom, the European Union and across Latin America. Cashew is a named allergen, so packaged foods must declare it on the label. Leaf and bark products are sold as food supplements and are not approved to treat any disease.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
One email with the summary. We'll also send a short weekly evidence update — unsubscribe any time.
