Frying, broiling, or grilling meats at high temperatures creates HCAs (heterocyclic amines), potent carcinogens implicated in several cancers. But HCA levels are significantly reduced when rosemary extract (a common powder) is mixed into beef before cooking, say Kansas State University researchers. “Rosemary contains carnosol and rosemarinic acid, two powerful antioxidants that destroy the HCAs,” explains lead researcher J. Scott Smith, PhD.

It might also: Stop tumors. Rosemary extract helps prevent carcinogens that enter the body from binding with DNA, the first step in tumor formation, according to several animal studies. When researchers at the University of Illinois at Urbana-Champaign fed rosemary extract to rats exposed to dimethylbenzanthracene, a carcinogen that causes breast cancer, both DNA damage and tumors decreased. “Human research needs to be done,” says study author Keith W. Singletary, PhD. “But rosemary has shown a lot of cancer-protective potential.”

Maximize the benefits: To reduce HCAs, Smith recommends marinating foods in any supermarket spice mix that contains rosemary as well as one or more of the spices thyme, oregano, basil, garlic, onion, or parsley.