Welcome to HCM
We understand your concerns
You have not mentioned your age. Do you have any medical conditions other than what you have mentioned? Gaining weight is directly proportional to food habits and being happy and success. First of all you are not happy or you are anxious about your health. Every person is unique and therefore for wanting more, requires special requirements. You have not mentioned your weight also. First confirm whether you are underweight
. Second don't loose heart, you are not alone. Third be happy and eat well (rigorous activities and exercise induce appetite and then you cannot resist eating).
Get well soon. good luck