Over a year's time, he lost half of his body weight - dropping from 417 to 196 pounds.
But Epstein says his weight loss wasn't just for him, but for his family and to help other people hoping to get healthy.
Today, Epstein looks like the picture of health.
Just 16 months ago, when he was chosen from "Extreme Makeover: Weight Loss Edition," he topped 400 pounds.
Epstein, always a jokester, learned he was on the show when trainer/coach Chris Powell turned the tables. When he stepped toward a lunchroom candy vending machine, confetti fell from the ceiling, a red warning light spun around, and Powell's voice boomed over the speaker, "Step away from the candy machine."
When Powell emerged to tell Epstein it was time to pack for his makeover, Epstein said, "It was a surprise of a lifetime."
At 50 years of age, Epstein is the show's oldest participant to date.
During his college years, Epstein was an athlete, keeping up a vigorous weight-lifting regimen. And his wife said that after their marriage, the couple frequently went on 25-mile bike rides. But eventually, Epstein began struggling with this weight.
Wife Nanci told the "Extreme Makeover" producers, "I joked with him that he put even more weight on than I did with each pregnancy. I took some of the weight off, but Mike never did."
He feared he'd face an early death. Indeed, show producers say he was the first participant to fail the routine physical exam (A heart scan showed the beginnings of blocked blood vessels.).
In addition, Epstein couldn't do all the things he wanted to as a husband and as a father to 18-year-old Ethan, 15-year-old Gabby and 10-year-old Aidan.
He told us, "I was always there for them emotionally, I could always take them to their game, I could cheer for them but I was a spectator and I wanted to be a participant."
Epstein's unhealthy weight was also hard on his wife.
"When I met my wife she met the real me; she met this guy who could be her hero, who loved her very much. I have changed so much since then, I have become a lot more withdrawn," he told show producers.
However, Epstein insisted on staying with the program, and Powell said his drive was more powerful than he had ever seen.
Trainer Chris Powell set the goal for Mike to lose half his body weight, but the focus wasn't just physical.
"He said this is not about losing weight, this is about transforming your life," Epstein says. "You can't say I have to do this, you have to say I want to do this,"
Epstein also began seeing a therapist who specializes in obese patients.
He says changing his mind, the way he thought about food and dealt with emotions was pivotal. And as weight started to come off, he felt even more motivated.
At his final weigh-in in April he weighed 197 pounds, a far cry from his personal high of 453 pounds. And his children couldn't be prouder.
"He feels good and he's happy so that makes up happy," says Ethan.
Gabby adds, "It's so fun to play sports with him in the backyard and have fun because he never did it before."
Aidan is just happy his dad can now join him on roller coasters.
Since April, Epstein has set a new goal: to build more muscle. And he has.
"This is really my new normal and I am constantly setting new goals for myself," he told Action News.
His advice to others trying to lose weight is: 1.) Enlist support from your friends and family; 2) Believe in yourself; 3) Take it one day at a time, one pound at a time.
Epstein admits he did face challenges and says everyone will face set-backs. But when you fall, get back up and keep moving forward.
He now hopes to "pay it forward" and help other people get healthy and happy.