hi,my age is 27,weight is 56 kg only,height 5''8 inch.i dont have any internal problem in bloods and all.My blood group is B+ .1 year before my weight was 64 kg.but with little tension for job i lost around 8 kg,my father is slim around 50 kg his age is 57and my mother is healthy balance weight,she don't have any weight issue. now i am trying hard to gain weight but not gaining a single gram.eating food properly also.Is there any medicine or tips to gain around 10 12 kg.its very very difficult for me to gain. Previously all the test blood and stool test urine test everything i have done which results came normal.please give me solution for this.