Judging.

I try not to compare myself and judge myself based on how others look. It can be hard to remember to do. Especially with famous people in the news and magazines and on tv. The internet is making it too easy to get into the judgemental mindset. They get caught looking bad in a swimsuit and everyone gets all judgemental. You know what? I want to see the person behind that sneaky camera. Celebrities, for the most part actors and singers, KNOW they will be judged on appearance and take pains to make sure they look good. They have the money for the tailored clothes and the consultants. People get photoshopped. When I go to a party, I've dressed myself and my friends snap pictures with their cameras. When a famous person goes to a party, they often have designer clothes measured to fit them. And the people snapping pictures are professional photographers with expensive cameras. Not to mention they are EXPECTING to be photographed...sometimes my friends sneak up on me or catch me in the background looking goofy. So comparing yourself to someone whose job it is to look good on film or screen is not the best way to do it.
Everyone judges. Everyone makes comparissons and thinks things such as "I wish MY legs looked like that" or "I'm really glad my stomach isn't THAT big".
I try not to, but I'm as guilty of gossip and "bad thoughts" as anyone else. I learned it from people around me and the internet and it's a tough habit to shake. I try to think "Well, maybe she doesn't have the money for healthy food choices and a gym membership. I certainly don't make time to work out. Everyone's body functions in its own way".
I have friends all over this spectrum. I have friends who have overcome weight problems and are healthy and in shape. I have friends who can't gain weight or muscle no matter how hard they try. I have friends who can't LOSE weight. I have friends who have eating disorders that they work everyday to not succumb to. I have friends who run marathons and/or work out daily. I have friends (like me) who generally do nothing special and are ok with how they are.

When I write the following I am going to try to not sound judgemental myself:
What I don't like is when people judge others based on how they look. As I said, I'm guilty too and I try to keep myself from thinking harshly of others. Just please don't sit and complain about how others are.
When you're overweight and you dislike "skinny" people it isn't fair. They might work hard to look that way. Or maybe they wish they had a bigger butt or more muscle. Writing a facebook status about how thinking about going on your beach vacation with skinny relatives makes you want to stay home is hurtful. 
When you're fit and judge people for being overweight, that isn't fair either. They might not have the resources or drive that you have. Maybe they don't even want or need to lose wieght. Tweeting about how some girls look like "busted biscuit cans" in tight pants is mean. Implying that people who don't work out daily or eat fastfood are lazy and unhealthy is rude.
Just think about what you say and how it might come across to others. That's all I have to say about that.