Omega-3 fatty acids are considered brain food because they perform two important functions in the brain. They maintain mood balance, and they assist in retaining memory. These foods include eggs, fish, walnuts, pumpkin seeds, and flax. Canola oil and soy oil are also good choices for foods containing Omega-3. Other types of fats like vegetable oils tend to be high in Omega-6 fatty acids. Research suggests that too much Omega-6 may be detrimental to brain health, may cause depression and can cause the damaged brain to post vanity posts on Free Republic.
Brain food derived from protein affects the neurotransmitters of the brain. Eggs and fish are both excellent protein sources because they both contain Omega-3. Another good choice is any product made from dairy. Beans are also excellent and serve as both carbohydrates and protein.
Personally, I use Omega-3 supplements, although I prefer fish. I enjoy fish and I love fishing.
I hope that helps you.