Six-hundred-pound mom Donna Simpson says she wants to be the heaviest woman in the world, and she's getting plenty of attention for wanting to gain more weight. "I feel very sexy," she tells ET's Diane Dimond.

Already a Guinness record holder as the heaviest woman to give birth, the 42-year-old mother of two tells Diane that she's very proud of her belly because, she explains, "It's the centerpiece of my fatness." She says she is also looking to double her 600-pound frame.

"Yeah, the thought of being bigger is just more attractive," she says, but she adds that she does not recommend it for her daughter.

"People ask me, 'Do you want your daughter to be fat?' and I do not want her to be fat," she says. "I do not want her to be fat … because not everybody can be as confident as I am."

The publicity Donna's getting on the Internet and on TV for her unusual aspiration is drawing some negative response, including threats on her life.

"I'll tell you, what gets me is when I see comments that I should die," says Donna. "Since we started this I've got death threats: 'If I ever see you, I'm killing you.' That bothers me. It bothers me that somebody would feel that way."

Donna's mobility is severely limited and she is on diabetes medication. In her quest to double her size, she says that she is doing it in a "healthy" way, cutting out cholesterol and avoiding fried foods.

"Some days I can have a thousand calories, some days I can probably have ten thousand calories," she says. "I've said to myself that I'm not going to limit myself; whatever I want to eat I'm going to eat."

Watch the video to see what Donna's typical dinner consists of.

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