In balance, I’m almost 6′ and probably no more than 65kg, people I havent seen in a while always comment that the forget how skinny I am. Often wear 28 jeans.
But, i’m fit, healthy and eat plenty, including healthy and unhealthy food. My base diet is good but with plenty of cake, toast, beer etc. Sometime though if I’m busy and not exercising I can get by easily on fairly low calories/day.
When I’ve tried to ‘put on weight’ i just end up feeling unhealthy and put on an inch or two of belly blubber which is not healthy. I’ve given up now and am just content with what I am.
Point is there might be nothing wrong!!!!