I think they are genuinely happy to be honest. being in the media spotlight and the pressure that all the skinny celebs say they are under to be slim, im sure if the likes of dawn and fern werent happy they would lose weight? I know there are a lot of women who are happier being bigger. I personally feel that curves are sexy, but some women may not, or may feel the bigger the better. They still get work despite their size, who knows if they would get more if they were slimmer, or even if they would get less if they to lose weight...
Saying that though, when you watch programmes with 'feeders' you wonder if these men and women just want to be loved and will do anything to have acceptance. If there partners like bigger people, are they happy to stay bigger for there partners?
Just look at Michele McManus who lost all that weight - she always said she was happy, then lost weight and said she didnt realise that she was kind of unhappy...