Renée Zellweger – Diet/30 pounds

Renée Zellweger was in the rare position of having to gain weight for a movie when she took the lead role in Bridget Jones’s Diary in 2001 and reprised it in Bridget Jones: The Edge of Reason in 2004. Each time she played the refreshingly average-sized character, though, Zellweger needed to set her sights on weight loss in order to film other roles. In the past, Zellweger has relied on the Zone Diet to slim down, an eating plan that closely balances the ratio of carbs, fat, and protein consumed.