Turkey, chicken and lean cuts of meat are loaded with tyrosine, an amino acid that can help you feel more alert and focused. If you’re not getting enough meat, and you feel yourself dragging through the day, you might be low in iron. Pump up your levels with chicken legs or lean beef. For an energy-boosting lunch, try a spinach salad with walnuts, turkey, blue cheese and dried cranberries, or a turkey and Swiss sandwich on whole-wheat bread.

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