Extended computer use has been linked to obesity, but a Michigan woman says her online activities helped her to shed 530 pounds.

Nancy Makin, 51, is scheduled to appear Wednesday on "The Oprah Winfrey Show" to talk about how she lost the weight in less than three years using an "Internet diet."

Makin, who weighed as much as 703 pounds, spent many years living reclusively in her one-bedroom Grand Rapids apartment. At one point, she had not been outside in more than three years.

"I probably went out of the house eight times in 12 years," she told The Grand Rapids Press for an online story posted Monday.

It wasn't until a relative hooked up Makin with a computer and Internet access that she started to slim down. While her weight made it difficult for her to interact with people in person, she discovered that she quickly made friends in online chat rooms.

"Anonymity was key," she said. "They couldn't look at me and judge me based on how I looked."

Makin said her online social life ended up working wonders on her figure as she stopped using food to bury her feelings of isolation.

"I wasn't trying to lose weight," Makin said. "I was just reaching out."

Her appearance on the Winfrey show was recorded Nov. 8. She said she hopes her story will inspire others looking to change their lives.

Makin, who now earns a living cleaning houses, said she hopes to one day become a motivational speaker.

"I think something might change," she said. "I don't think I'll be scrubbing toilets for much longer."