Even though Kirstie Alley is trying to slim down on her reality show Big Life, she admits she had a blast packing on the pounds.
"It was the greatest thing in the world getting fat. Every meal out was an event," Alley, 59, tells the May issue of Ladies' Home Journal (on stands April 13). "We'd go to Italy and have pasta, truffles and dessert and then plan the next incredible meal. It was a happy-go-lucky time. I never had so much fun."
PHOTOS: Stars who love their curves
But after Alley discovered she weighed 230 pounds, she was horrified -- especially after she'd touted her 75-pound weight loss on The Oprah Winfrey Show in 2006.
"It was insane. I'm disgusted with myself! I let myself down and, worse than that, I let other people down," she says. "People were looking up to me for losing all that weight and then I went and got all chub on them."
PHOTOS: Stars who have been mocked for their weight
Alley admits she was in denial about her ballooning figure.
"When we get fat, we fool ourselves with every kind of lie imaginable. By 2008, my weight started creeping up and I said, 'Oh, I still look good at 150. I still look good at 155. I still look okay at 165. Some of my clothes still fit at 175,'" she says. "And nobody was saying 'You're fat.' I was like a bank robber who was getting away with it."
VIDEO: A celeb trainer explains a quick workout
She credits Scientology for helping her come to terms with the weight gain.
"Scientology helps you lose your insanities. One of the keys is to say, 'You're in charge of your life, buster. You're responsible for any condition you're in,'" she says. "I've been irresponsible many, many, many times and that has resulted in me being fat."
PHOTOS: Step-by-step no-gym workout plan
Alley also looks to another Jenny Craig spokeswoman as inspiration: Valerie Bertinelli, who shed 40 pounds.
"I admire her and her abs so much, but, man, am I jealous. I honestly believe she won't gain her weight back," Alley laments.