Over the years, neuroscientist and brain-imaging expert Dr. Daniel Amen has refined nine rules of brain-healthy eating.

1. Think "high-quality calories" and not too many of them.
2. Drink plenty of water and not your calories.
3. Eat high-quality lean protein throughout the day.
4. Eat smart carbohydrates (low glycemic, high fiber).
5. Choose healthy fats.
6. Eat from the rainbow.
7. Cook with brain-healthy herbs and spices.
8. Make sure your food is as clean as possible.
9. If you're having trouble with your mood, energy, memory, weight, blood sugar, blood pressure or skin, make sure to eliminate any foods that might be causing trouble, especially wheat and any other gluten-containing grain or food, as well as dairy, soy and corn.

Daniel Amen, M.D. heads Amen Clinics, which are located in Orange County, Calif., Atlanta, San Francisco, New York City, Washington, D.C., and the Seattle area. He has written numerous books, including "Healing ADD" and "Change Your Brain, Change Your Life."