Fat, thin, short, tall - we're all different. But how you look is one thing that you told us you worry about.
Newsround's Ellie went to find out more by having a chat with agony uncle Aaron Balick.
So why are we so obsessed by the way we look?
It's for two major reasons. The first is that we want to make a good first impression.
And the second reason is that we compare ourselves with people in the media and magazines.
These people are airbrushed, work hard with personal trainers and we can't compare ourselves to them.
Why have we become like this, trying to be thinner and prettier and so on?
Good question. The culture we live in is image based. Many things are sold on image. Big images on billboards get our attention, and it's the same with TV and movies.
And it's about what people think is the most important thing getting mixed up. We see images everywhere, and we're fooled into thinking 'that's about me'.
But it's not just about looks. It's about wider things like the way you think, having good ideas, being artistic or enjoying sport.
If you get upset, how do you get over it?
This is one of the things that's easy to say and tough to do.
When you look at magazines, there's sometimes a voice in your in head that talks to you in a nasty way.
The trick is to become aware of that voice and tell it to stop and replace it with more positive things, for example, what makes you happy and what makes people like you?
Everyone says it's the inside that counts. Is that unrealistic?
My advice is to focus on what you want to appear good at, and not focus on first impressions.
Find things that make you feel good about yourself and develop them, then image will matter less.
Should we blame celebs?
They are not to blame. A lot of models and celebrities are caught up in themselves. It's important to remember they might feel as bad about themselves as we do.
What if you get the mickey taken out of you at school? How can you shake it off?
You need to look at all the people around you. Everyone is slightly different.
One of the important things is not to make it so personal.
Look in a mirror, but also look at everyone else - I'm wearing glasses and am bald - lots of people out there are like this.
The second thing is to be a leader not a follower - who made them the fashion god or body god?
If they don't like it, well that's their business.