To lose weight, exercise more or eat fewer calories than is recommended. To gain weight, increase the number of calories you eat while maintaining a moderate activity level. Read more about making smart food choices and find recommendations of how much to eat, organized by activity level.

Start by increasing your calorie and protein intake by eating every few hours. Take supplements, if needed, for that extra boost. Work out hard in order to turn any extra calories into muscle, not fat. If you plateau or need additional help, talk with a dietitian or personal trainer.

Increase your caloric intake If you want to gain weight slowly and steadily, try aiming for 300–500 calories more than you burn each day according to the calculator. If you want to gain weight fast, try aiming for around 700–1,000 calories above your maintenance level.