Hi Sir, I think I am below weight than it should be according to my height and age. But I am stressed about how should I gain it in natural way without taking any artificial help. And the most important thing is I can not digest milk I dont know why. Whenever I drink milk or eat milky product I lose weight and become weak. Strange actually. What should I do to increase my weight and muscles in natural way and continue the trend after achieving the goal? Thank You.