Growing Pains actress Tracey Gold, who fought a highly publicized battle with anorexia, isn't the show's only star to battle the bulge. According to her TV dad

Alan Thicke, the upcoming Growing Pains Movie reunion (Sunday at 7 pm/ET on ABC) has him headed for the gym.

"I had to go into donut rehab for a couple of weeks just to make sure I could approximate Jason Seaver again," the actor told the TV Guide Channel about reprising his Pains alter ego. "If you look back to the very beginning of the series, we were all lighter, our hair was darker and our tummies were flatter.

"The toughest part of going back to that character was looking at the tapes and seeing that [Jason] was at least five pounds lighter," adds Thicke. His co-star Gold agrees: "It's still hard for me to look back at some of the outfits I wore and hairstyles and things like that. I just cringe."

But after eight years, TV's idealistic '80s family is ready to show us their smiles again. Although, teen heartthrob Kirk Cameron admits having his adolescence played out on TV left him with his own personal growing pains.

"Growing up on television is part exciting and part nerve-wracking," explains Cameron, now father of four. "It's not the best place for kids to grow up because you are really living your life in a fish bowl. When millions of people are watching everything that you do and say, you get very self-conscious and self-aware. [But] it's been an experience that I'm forever grateful for."