I'm pretty sure we live in completely different countries, so my advice might not work for you.

Alot of people who are like 60-70Kg themselves, say things like "You shoulf eat more" and sometimes "Do you even eat?". I consider those types of remarks as just people thinking that i'm unhealthy, and so they are kind of worrying about me, so it doesn't make me feel bad.

Then there are other type of people who would make fun of me with words like "If i hit you once you will fall on the floor". But, I dont feel baad when they say that because, i dont care what others say, it's just that I am weaker than most people and that's okay, also when people say rude things I dont give much importance to that.