These following steps may help: - Don't skip meals, you may not feel like eating but in such conditions you should have the reduced amount in frequent intervals(i.e. 3 square meals broken down to 5 or 6 as you can tolerate) and slowly increase as you get better. - Reduce/ Avoid spicy,fried, fatty, junk and oily food - Exercise regularly and convert the food eaten into energy and muscle - Increase daily intake of water to 3 liters - Avoid/Stop smoking and drinking if you have the habit - Reduce stress through methods such as yoga/meditation. By eating more and having unhealthy junk food will also increase your weight but that is an unhealthy increase, so you should exercise regularly to make it into muscle gains.