Researchers have known for decades that beans, in addition to their high fiber and protein content, are a rich source of antioxidants. In fact, a study published in the Journal of Agricultural and Food Chemistry in 2003 reported that, gram for gram, black beans had more antioxidant power than any of a dozen other common varieties of dry beans tested.
In general, darker seed coats were associated with higher levels of flavonoids, and therefore higher antioxidant activity, according to the researchers. The most active antioxidants in the beans were anthocyanins, which the researchers found at levels similar to what are contained in an equivalent serving size of grapes, apples or cranberries. The researchers noted that the beans are also rich in protein, carbohydrates, folate, calcium and fiber.
3. Jalapeños
Jalapeño peppers are a good source of antioxidants, but not all of the hybrids are equal, according to a study . If you want the strongest antioxidant activity, choose either an El Dorido or Grande variety over a Tulsa, Sayula or El Rey hybrid. The researchers noted that the Grande and El Dorido hybrids had significantly higher levels of carotenoids, vitamin C and capsaicinoids than the other jalapeños they tested.
4. Tomatillos
Tomatillos, which look like green, unripe tomatoes that have been wrapped in a dry husk, are the star ingredient of green salsa verde. And, it turns out, the slightly acidic fruit may have some anti-inflammatory qualities, according to a study. The study found that the sticky material (sucrose esters) on the surface of the tomatillo fruit may inhibit inflammation much as aspirin and ibuprofen do.
5. Cilantro
Cilantro, a leafy green herb, has been valued for centuries for its medicinal properties — although those benefits appear primarily to be found it its dried seeds, known as coriander. It contains “bioactive phytochemicals that are accounted for a wide range of biological activities including antioxidant, anticancer, neuroprotective, anxiolytic, anticonvulsant, analgesic, migraine-relieving, hypolipidemic, hypoglycemic, hypotensive, antimicrobial, and anti-inflammatory activities,” according to a 2018 report published in Food Research International.