I am a 22 year old male. Over the last few years I have lost weight. I do not know why but I have tried every way to gain some weight but I can not. I consume enough calories throughout the day and I do resistance training as well but it's like I still I have problems maintaining my weight. I Have started to remain depressed due to this as well. Do I have a disease? Should I get tested for loss of weight? What should I do? Please reply.