Kelly Mason Becomes Second 'My 600-LB Life' Subject To Die During Show's Filming, Suffering Heart Failure

Nathan Francis

Kelly Mason came to My 600-LB Life determined to turn her life around --- and did, losing more than 300 pounds --- but it came to a tragic end when she suffered a heart attack in her sleep.

She became the second person to die during the filming of the TLC docu-series, which chronicles the efforts that morbidly obese people are taking to lose weight. In the March 27 episode, Kelly endured a painful journey to Houston to seek treatment with world-renowned weight-loss surgeon Dr. Younan Nowzaradan. Kelly was nearly immobile due to her enormous weight gain, and during the day-long trip to Houston, she fell out of a cab.

Kelly became determined to lose weight, and over the course of her My 600-LB Life episode, fans saw her lose more than 300 pounds. Unfortunately, she suffered a heart attack while sleeping last month.

Kelly Mason now becomes the second participant on My 600-LB Life to die during the filming of the show. In late 2017, Robert Buchel also passed away while production of the show was still taking place. The network aired the episode in March 2018, and his fiancee, Kathryn Lemanski, spoke about his final days.

"He told me, 'I don't think I'll make it through the night. I love you and I always will,'" Lemanski said, via USA Today.

"I lost my best friend and the person I was supposed to spend the rest of my life with."

By the time the My 600-LB Life episode aired on Wednesday night, some fans had already learned of Kelly Mason's death, even sharing an obituary that was posted online last month. The death notice reported that Kelly had passed away on February 15.