Cooking with rosemary can put you in a healthy state of mind for years to come. The fragrant herb contains carnosic acid, a compound that signals the brain to defend itself against free radicals (harmful by-products of metabolism that can cause stroke and Alzheimer’s disease), according to a study published in the Journal of Neurochemistry. Keep your brain strong and healthy by tossing freshly chopped or dried rosemary over salads or using it in meat, fish, and vegetable dishes.