I was one of those hyper skinny people. There are only two reasons for it: 1) a temporarily very high metabolism that will fade with age 2) how many calories being consumed in relation to how fast your body burns
I couldn't gain a pound of weight no matter how much crap I ate, right up to about the age of 25. So I ate anything at any time, all the time. I then proceeded to gradually gain 40 pounds over seven years, from 150 to 190 (at a 6'2" height), as my metabolism slowed.
I lived off of sugar, all the time. And pasta carbs.
You'll find that some of the formerly skinny types that keep up that rubbish diet, will end up remaining slightly thinner than most except for some out-of-place looking weight gain in the mid section. That's the lucky scenario. The unlucky scenario is you give yourself diabetes or your metabolism really lets out and you just explode to twice your size.
I don't know if you've visited r/fitness or r/gainit, but metabolism really only accounts for a variance in about 200 calories. The big thing holding skinny people back is that they pretty much aren't eating enough of the good stuff - sure a skinny person might eat 3 cheeseburgers in a sitting but it doesn't help that their only exercise is cardio, or that it's the only substantial thing they actually eat all day. Many self professed skinnyfat people who claim they eat like a horse are shocked to find that they aren't consuming nearly as much calories as they think they are when it's all being tracked.
Did you actually religiously track your calories in/out?
You'll find that some of the formerly skinny types that keep up that rubbish diet, will end up remaining slightly thinner than most except for some out-of-place looking weight gain in the mid section. That's the lucky scenario.
The out of place weight gain in the mid section is actually a really good warning of future heart problem. So even that lucky scenario is not as lucky as it appears.
I couldn't gain a pound of weight no matter how much crap I ate, right up to about the age of 25. So I ate anything at any time, all the time. I then proceeded to gradually gain 40 pounds over seven years, from 150 to 190 (at a 6'2" height), as my metabolism slowed.
I lived off of sugar, all the time. And pasta carbs.
You'll find that some of the formerly skinny types that keep up that rubbish diet, will end up remaining slightly thinner than most except for some out-of-place looking weight gain in the mid section. That's the lucky scenario. The unlucky scenario is you give yourself diabetes or your metabolism really lets out and you just explode to twice your size.