Question: how to gain weight quickly after illness?
Answer: Milk. Share on Pinterest Protein shakes can help people gain weight easily and are most effective if drunk shortly after a workout. ...  Protein shakes. Protein shakes can help a person to gain weight easily and efficiently. ...  Rice. ...  Red meat. ...  Nuts and nut butter. ...  Whole-grain breads. ...  Other starches. ...  Protein supplements.