Take Omega-3 fatty acids
Two types of omega-3 fatty acids are abundant in seafood-eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). In humans, high DHA levels are linked to raised levels of dopamine and serotonin, the same brain chemicals that antidepressants boost. What's more, a shortfall of DHA in animals has been linked to symptoms and markers that mimic depression. "You're at greater risk of being depressed, anxious, and irritable by avoiding fish," says Joseph R. Hibbeln, M.D., acting chief of nutritional neurochemistry at the NIH's National Institute of Alcohol Abuse and Alcoholism.
Eat cold-water fish (salmon or mackerel) at least twice a week. Otherwise, take a daily 1-gram dose of omega-3 fatty acids with a 2-to-1 ratio of EPA to DHA. This makes for good brain food, because EPA seems to hold more sway than DHA over mood and behavior, according to Parris Kidd, Ph.D., a nutrition educator and contributing editor for the Alternative Medicine Review. It takes 8 weeks for most people to feel a full response kicking in.