Jewel was crushed when she was called "the chubby Renee Zellweger" in the press a few years ago.
"My feelings were so hurt by that story, I ended up bingeing on an entire cake," the singer, 36, tells Shape magazine (via JustJared). "Afterward, I actually tried to throw it all up, but thankfully I couldn't do it."
Jewel goes on, "It made me think, 'I can't go down this road.' I had seen so many performers develop eating disorders or try to control their weight with drugs, and I decided I would do no harm to my body."
Jewel (who wed pro rodeo cowboy Ty Murray in August 2008) says that "women are so critical of themselves."
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"We can be gorgeous and hot and still be embarrassed to wear a tank top," she adds. "So if you can't stop looking in the mirror, at least try to not think badly about yourself when you do."
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"We should be more like men, God bless 'em. They can take their shirts off and show their man boobs, and they don't give a hoot," she says.