Milla Jovovich
Supermodel and actress Milla famously gained over four stone when she was pregnant. Eating two boxes of doughnuts a day, she weighed in at almost 14 stone when she gave birth. In true Hollywood style, she lost 62 pounds in five months in order to shoot swimsuit scenes for her next film. Hope she's got those doughnuts under lock and key!
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Mel B
Spice girl Mel has always had a great figure, but since she moved to the US her body has transformed into something almost superhuman. She slimmed down in training for Dancing with the Stars last year and has been doing intensive workouts to get a six-pack any bodybuilder would kill for.
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Kirstie Alley
Actress Kirstie appeared on Oprah Winfrey's show in 2006 in a bikini to show off her weight loss of five stone, but has since regained the weight to tip the scales at over 16 stone. She admits a love for butter, sugar and Chinese food, but promised Oprah she would drop back to 10 stone by the end of the year.
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Jennifer Love Hewitt
Actress Jennifer was publicly slated for unflattering paparazzi pictures of her in a bikini on the beach in 2007. At the time she said: "a size two isn't fat…being a size zero doesn't make you beautiful". Since then she's lost over a stone with the help of a trainer, so she must have changed her mind.
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Britney Spears
One moment Britney's clutching a frappuccino and her pot belly, then suddenly she's snapped on the beach looking fabulous in a skimpy bikini. The singer's body seems to change faster than the weather, although she has sustained her weight loss in 2009 from all the exercise she's being doing on tour. Don't let it slide when you get home, Brit!
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Nicole Richie
Photos of the super skinny socialite are a valuable lesson in knowing when to stop dieting. Rumoured to weigh around 6 stone 11 pounds at her lowest, Nicole managed to gain weight during her first pregnancy. Let's hope she doesn't feel the need to diet back to her old skeletal shape.
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Janet Jackson
The poster girl for massive weight loss - and gain - in Hollywood is undisputedly the singer Janet Jackson. The star gained four stone in 2006 and then shed it all in four months on an extreme diet and exercise programme. She then regained three stone in 2008, before losing it again this year. Ever heard of the middle ground, Janet?
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Mischa Barton
After receiving digs about her 'cankles' the already slim star went on a serious diet, debuting a decidedly waif-like frame at the Paris fashion shows in 2009. However, something seems to have happened to Mischa because although she has retained her slim frame, her face is looking decidedly puffy and bloated in comparison. She looks as if she has had too many nights out and not enough sleep.
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