How do you fatten your body up in a healthy way?

Answer 1

Eat and drink more calories than your body needs, eating healthy foods. If you need to consume a large amount of calories, eat more calorie-dense foods so you don't need to eat massive amounts. Use of Healthy Fats like Olive Oil, Avocado, etc, come in handy. Drink caloric beverages - full cream milk has a good amount of protein and calcium to help bulk somebody up. Easiest thing to do would be to figure out how many calories you burn in a day, and try to consume 500 - 1000 more. Eat healthy foods doing it, and there you go.