Educational information, not medical advice — ask your doctor or midwife.
Annatto is a red-orange dye made from the seeds of the Bixa orellana tree. In the Caribbean it is known as roucou, bija, achiote or woukou. Cooks use it to colour rice, stews, fish, oils and cheese.
The seeds carry a waxy pigment on the outside. Steeping them in hot oil or water pulls the colour out. That coloured oil or paste is the form most home kitchens use.
Here is the honest verdict. As a food colour, annatto is well known, widely allowed and safe for most people. As a remedy, human evidence is very thin, and long use in Caribbean homes is not proof that it treats anything.
No one has shown how annatto works as a medicine, because it has barely been tested that way in people.
Its colour comes from carotenoids, the pigment family that also colours carrots. In test tubes, these pigments mop up free radicals. That is an antioxidant effect in a dish, not a proven effect in a body.
In animal studies, annatto extracts have changed blood sugar. Some reports show a rise. Others show a fall.
Lab tests also suggest the seed extract slows the growth of some bacteria and fungi. Whether that does anything on human skin is not known.
Annatto seeds also hold tocotrienols, part of the vitamin E family. Vitamin E is a real nutrient with real effects in the body. That does not mean annatto capsules treat any illness.
Whole seeds are the base form. Cooks steep them in hot oil or fat, then strain them out. The coloured oil is called roucou or achiote oil.
Ground seed powder and achiote paste are sold in jars and blocks. Sazon and adobo seasoning mixes often contain annatto too.
Food makers use liquid extracts, listed as annatto extract or E160b. You will find them in cheddar, butter, smoked fish and snack foods.
Supplement shops sell annatto delta-tocotrienol capsules. Some also sell plain seed powder capsules. Soaps and skin oils with annatto exist as well.
Annatto has a long record in the Caribbean and tropical Americas. Taino, Carib and other Amerindian peoples painted the red paste on skin and hair. It marked status, and was said to guard against sun and insect bites.
Island names carry that history. It is roucou in Trinidad and Tobago and Dominica, bija or achiote in Cuba and the Dominican Republic, and woukou in Haiti.
Home traditions also used seed and leaf teas for fevers, upset stomachs and skin sores. Pastes were spread on burns and bites.
Spanish and French traders carried the dye to Europe. There it became a standard colour for cheese and butter, which it still is.
Call emergency services if your lips, tongue or throat swell, or you wheeze or struggle to breathe after eating annatto. Those are signs of a severe allergic reaction.
See a doctor soon if you get hives, an itchy rash or face swelling after annatto foods. Stop using it while you wait.
Stop capsules and call your doctor if you feel shaky, sweaty or confused, which can be signs of low blood sugar.
Also see a doctor if a skin sore you have treated at home gets hotter, redder or more painful.
Annatto is an ordinary food ingredient in most countries. In the UK and EU it is an approved colour, listed as E160b. In the United States the FDA allows annatto extract as a colour additive, and capsules are sold as supplements rather than medicines.
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.
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