Hello, I am 20 years old, 5'11 and about 120 pounds (hover a pound or two below or above 120). My ribs still show and like the bottom parts of my rib cage, (left and right) are visible and if someone were to touch me around that area, chest or lower chest, they can easily feel that bone. Other than my ribs I'm pretty boney all around. I don't understand why I'm so underweight I have a normal, healthy diet. I would say I eat much more than a lot of people that weigh more than me and I just don't understand. Is it a super high metabolic rate or something? Intestinal parasite? What can I possibly do to gain weight? (mind you it literally seems like an impossible fantasy to gain any weight for me no matter what I do) Any advice other than the obvious eat more or work out? At this point eating an excess amount of food just seems wasteful because it seems like my body just devours and shows no results whatsoever. I eat normal sized meals but throughout the day I am CONSTANTLY hungry, like I need to be constantly snacking throughout the day in order to satisfy my hunger. This is just getting very frustrating for me now because I always thought as I get older I would get better but I'm 20 and nothing has changed, I have actually gone down like 5 pounds since last year and I dont understand why. Please help. I am very very desperate to gain weight at this point
Edit - I feel I'm also big boned as other skinny people I know still don't show as much as I do e.g. on the wrist and such so that isn't a great combination
I'm in a similar position; I'm 22, about 5"8 and have never, ever managed to surpass 60kg (or 132 lb for the N.Americans amoung us). Less extreme than your situation, but still, its impossible to gain weight and very hard to simply maintain it.
If you in any way suspect parasitic infection, look up some common symptoms, then GET TO A DOCTOR. This seems somewhat unlikely though so I'm going to guess that we're just cursed with a more efficient metabolism than usual.
I know you said that you already eat plenty, but have you considered a work-out diet? One that involves lots of protein and counting your calories? I know from experience that what we THINK is enough food to gain weight, and what actually IS enough can be suprisingly different. A decent personal trainer at a decent gym might be able to help you out on that front (and they'll udnerstand that different people have different metabolisms. Just.. be wary of supplements they may suggest, and do NOT accept any under-the-counter advice about steroids).
In the end, it's your body and you know best. Personal experience; I just accepted that I'll never be huge and I've worked with what I've got. Strength training (for tone, rather than muscle size) helped with my body image, and might be appropriate for you as you say you still feel like you have flab.