I have been a losing weight unintentionally since year, i am trying to gain weight but it's not working.still i am losing a weight i m about to turn 21 and current weight is 45 and my eating is also healthy&good then what is still causing weight loss?

Doctor to evaulate: If one is truly underweight (based on height, family background, and body type), a Dr. can evaluate for a hormonal, digestive, or other disorder. If no medical cause is found, then one can add weight by eating more calories of nutritious foods, while also doing weight-training to increase muscle. Proteins: egg white, chicken breast, salmon,... Better fats: olive oil, peanuts, almonds, tofu,...