Is it a good thing if someone is proud of their size (obesity)?

My sister has this good friend who is extremely obese. She’s one of the nicest people you’ll meet. She is one of those girls that posts herself in bikinis, revealing clothing, and constantly preaches about pride for fat women. She constantly puts up this site http://adipositivity.com/ for women to be proud of their size.

I know it’s a good thing to accept who you are. It’s a lot better than being depressed. But do you think it’s very unhealthy and bad to be proud of being obese? Do you think if they were given the chance to lose weight they would? I’m not talking about chubbiness, a little rolls, or being a bit overweight…I’m talking about OBESITY here.