John decided to get thinner because he was worried about dying too young from illnesses caused by excess weight.
During her second pregnancy, Kim didn’t try to hide the fact that she’d gained a lot of weight. But she set herself the goal of returning to the "Kim of 2010″ in a short amount of time, and she certainly achieved it.
Chris lost weight in order to look the part as the leader of the team in Guardians of the Galaxy.
Christina decided to get in shape as a wedding present to herself.
Jonah explains his weight loss by the fact that he had previously reached a critical point where his weight threatened his life.
Mariah lost weight for the sake of her wedding to an Australian billionaire, in an attempt to achieve a figure she thought was fitting of her new status.
Christian took the risk of losing so much weight for the sake of his role in The Machinist.
Seth lost weight for the sake of his role in The Green Hornet. The combination of exercise and dieting were apparently hard to endure.
Kelly was forced to lose weight in order to completely transform her lifestyle.
Zach was prompted to lose weight by his marriage to his girlfriend, Quinn Lundberg. Later, the desire to star in more serious movie roles also influenced him.
Matthew lost a serious amount of weight for his role in Dallas Buyers Club. The actor even said he enjoyed the process.
Changes in her weight almost drove Jessica Simpson to a nervous breakdown. But her upcoming wedding forced the star to get a hold of herself.
An incredibly strong motivation to be slim allowed Janet Jackson to lose those hated kilograms.
After many years of what seemed like a hopeless struggle to lose weight, Oprah found the ideal solution: she found a company that offered various products and services that made it easier to lose weight. The results are clear for all to see.