Not only what you eat, but when you eat can have a profound effect on your energy level.
* Eat regular meals and snacks. The golden rule for high-energy eating is to keep your blood sugar (aka glucose) steady by never going more than four or five hours without eating. Glucose is the brain's main fuel. When it dips, you get that foggy tired feeling.
* Include some protein in each meal. Lean meat, fish, beans, eggs, low-fat dairy and nuts all count as protein. So get that pasta dish with some chicken and shrimp in it, or add beans and nuts to your lunch salad.
* Avoid large meals. No one knows exactly why, but large fatty meals make you feel tired. Keeping meals light helps keep you energized. So put down your fork when you reach a 5 or 6 on a scale of 1 to 10.
* Stay well-hydrated. Fatigue is one of the first signs of dehydration, so make sure you drink enough. On average, women need nine cups of fluid a day and men need 13.