I'm 22yr old, past six yrs my body weight was 43 to 44 kg....so.what that problem... Weather, gene or chromosome problem.... Tell me how to improve weight?
Do you want to gain weight? 43 or 44kg is roughly 94 or 97 lbs and for most height classifications that would be considered underweight... Of course there are ways to gain weight safely just as there are ways to lose weight safely. If you think there is some sort of illness that is making you be underweight, I would definitely consult a doctor before taking action. Best of Luck!
Also, how tall are you?