Exclusive: An 'Extreme Weight Loss' Star Proposes!

After shedding nearly half his body weight with the help of trainer Chris Powell on Tuesday's episode of Extreme Weight Loss, 32-year-old Mehrbod Mohammadi gained the confidence to propose to the love of his life, Mona, and ET cameras were there to capture the emotional moment!

Formerly 434 pounds, the now-slim music producer and DJ, devised a plan to pop the question with the help of our correspondent Rocsi Diaz, and the reaction was priceless.

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Responding with shock and shrieks of surprise, Mona said "yes," and her smitten, soon-to-be husband, who explained to ET why he was committed to making the petite brunette his partner for life.

"She chose to be with me when I was mortally obese, and she loved me for who I was," he smiled through happy tears. "That made me want to get healthy for the rest of my life so I could be there for her, because going the route I was, I wouldn't have made it to 40."

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Click the video to see the emotional proposal!

Extreme Weight Loss airs Tuesdays on ABC.