Hello, I'm 18 and no matter what I do, eat, use, I just cant gain weight. I'm 183 cm and I am 58 kilograms. People say that I at least need to be 75 kilograms considering my age. What should I do, I'm so skinny that I started having self esteem problems I dont wanna go out anymore? Should I go see a doctor, get my hormons tested or start using medicine? Using weight gainer products such as "mass weight gainer" end etc. would help me? Please help me out, please! Thank you.