Rob Kardashian is reportedly down 40 pounds after putting on more than 100 in the past few years.
Sources told TMZ the 28-year-old reality star is losing weight through diet and and exercise with girlfriend Blac Chyna's encouragement and help.
Kardashian is said to have given up red meat and carbs while working out five days a week with a trainer. Insiders told the website the couple made a "no cheat days" vow and are motivating each other to stay on track.
Kardashian and the 27-year-old model posted videos of themselves going through the reality star's cupboards Friday on Instagram. Blac Chyna okayed healthy foods, such as quinoa, but gave a firm "no" to sorbet and tortillas.
"It's just sometimes in life you have to eat healthy," the model explained. Kardashian was diagnosed with diabetes after an emergency hospitalization in December and is working to improve his health.
"Everything about him has changed," a source told Us Weekly of Blac Chyna's influence on her beau. "She's been so good for him."
Kardashian's sister Khloe Kardashian and mom, Kris Jenner, have both said the star's hospitalization was a wakeup call. Khloe Kardashian dedicated a throwback post to her brother Thursday, letting him know she's missing him amid his new romance.
"Rob has fallen hard for Blac Chyna," an insider told People magazine. "She makes him super happy and this is the first time that he's felt so optimistic about life in years."
Kardashian retreated from the spotlight after his weight gain, but has been active on social media since he started dating Blac Chyna in January. The reality star was all smiles in a kiss photo with the model on Snapchat last week.