How do people remain skinny?

For me, after every time I eat a pasta meal, I get fatter and bloated the next day. After I eat a subway sandwich or a rice bowl from chipotle, my stomch is immediately puffier and doesn't go away even days later. I would have to not eat any more carbs for the rest of the week in order for my belly to flatten back.

In order to maintain a slim waist, i have to eat salad 2 times a day or eat child sized portions of carbs/meat.

But I dont Think most thin people eat 2 salads a day. I think some people are just born to be thin, no matter what they eat. Its just harder for them to get fat

I see thin youtubers who eat literally all the carbs and unhealthy food on earth that still remain skinny

Then you have people like me who get fat immediately after a subway sandwhich. Then i get made fun of for "eating too much food".

How do people remain skinny?
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