Rob Kardashian Gains 50 Pounds, Starts a Diet and Exercise Program

USMagazine, Thursday, February 21, 2013, 4:15pm (PST)

Rob Kardashian is on a mission to lose the weight he gained during his year-long romance with Rita Ora. In the Feb. 17 episode of Kourtney & Kim Take Miami, the 25-year-old sock designer blamed his turbulent romance with the 22-year-old pop star for expanding his waistline.

"It's crazy how this whole year, my whole relationship was only negative. All I did was gain f-cking 40 pounds and lose so much money," he said on camera. "I'm so insecure. I weigh like 215 pounds. I hate pictures. I hate everything."

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Kardashian gained another 10 pounds after the episode was filmed. He began documenting his weight loss plan via Twitter and Instagram on Wednesday, Feb. 20. "This is what fat boy now has to eat for breakfast today. So much fun!" he wrote in the caption. "Cardio time."

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He shared an Instagram picture of "another fat boy breakfast" on Thursday, Feb. 21. "Let's go! Five-mile run next," he wrote. "Fifty pounds gots to go!"

The E! reality star received an overwhelming amount of support from his Instagram and Twitter followers. "Fat boy? Don't be so harsh. All this discipline can only translate to good things in your life," one user wrote.

Said another, "You don't have to talk down on yourself because you gained a little weight. You're dieting! And remember, beauty come in all shapes and sizes. Don't let what others think kill your vibe."

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Before Kardashian competed on Dancing With the Stars in 2011, he hoped participating in the ABC competition series would inspire him to stay more active. "You probably wouldn't know, but I'm the most insecure and overweight I've ever been," he confessed to Us Weekly before showing off his moves with pro partner Cheryl Burke. "I'm over 200 pounds, so I want to drop weight and this will be a good start."

This article originally appeared on Usmagazine.com: Rob Kardashian Gains 50 Pounds, Starts a Diet and Exercise Program