Updated: Oct 27, 2020
"Just what's in your za'atar depends, in part, on where you are in the Mideast. But generally speaking, it involves some combination of ground dried oregano, thyme or marjoram, ground sumac, toasted sesame seeds and often, salt.
As for za'atar's reputation as health food, that goes way back, too. In the 12th century, the great Spanish Jewish philosopher Maimonides is said to have prescribed it to his patients to treat a variety of ailments.
Modern studies into za'atar confirm that Maimonides was really on to something. Sumac is full of flavonoids, and thyme and oregano are both packed with thymol, an essential oil, and carvacrol, a phenol. Both thymol and carvacrol have antioxidant, antiseptic and fungicide properties. Thymol has also been shown to help control coughing fits in patients with bronchitis (which might explain why Maimonides recommended za'atar to treat colds).
But is za'atar brain food? Well, there's this tantalizing tidbit about carvacrol: At least in mice, it seems to travel from the blood into the brain relatively easily. Researchers are really just beginning to explore what it does once it gets there. For example, a study published this May found that, when administered orally to rats, carvacrol affected levels of the neurotransmitters dopamine — which plays a key role in the brain's rewards system — and serotonin, which is important to learning and mood."
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