Get some carbs

Carbohydrates stimulate the production of the feel-good hormone, serotonin. Research has shown that those on a diet tend to get depressed, a week or two down the line. About the time their serotonin levels dip, owing decreased carbohydrate intake. The next time you're feeling low, turn to some healthy carbs: whole-wheat bread, rice, cereal, rotis, parathas and fruits like banana, pear, and apple. You'll feel an instant lift.