Carrie Underwood may carry the bulk of her weight in her flowing, fussy tresses, but she's become the latest fat-free starlet to fess up to self-image issues (see Knightley, Keira).

"I think about what I look like probably more than I should. But I think everybody is her own worst critic," the slim-line country belter admits in the May issue of In Style. "Some days I step out of the shower, put my lotion on, and I'll be like, 'Ugh, ew, ew.'"

Carrie is so concerned with her appearance that she rarely leaves the house without makeup and meticulously jots down every morsel of food that crosses her lips.

Carrie silently curses her food diary for helping her fit into this unsightly dress.

"I'm OCD like that," acknowledges the onetime "American Idol" winner. "I count calories, fat and fiber -- which is important in making you feel fuller faster -- and protein, especially when I'm working out."

Still, "I'm content with 90 percent of me," she insists. "I like my teeth. Sometimes I wonder if my orthodontist realizes how important he was."

Underwood blames her waistline watching on the critical eye of the public: "If I put on five pounds, it's noticed immediately."

That said, she's willing to forgo her draconian dietary restrictions when she's dealing with a breakup.

"I'm a 'let it go, move on' kind of person. And ice cream is my friend," says Carrie. "If anybody sees me eating a sundae and I look unhappy, something bad has happened. I am drowning my sorrows in fudge and caramel and whipped cream."

Her seemingly unhealthy relationship with food likely came into play after her recent text-message split with "Gossip Girl" eye candy Chace Crawford and her fizzled pairing with quarterback Tony Romo.

"Now I'm to the point where you get one shot," she says of wading into the dating pool. "Life's too short."

Especially when the guy has a wandering eye.

"I've been cheated on a time or two. It's tough," concedes Carrie, who cautions against taking inspiration from her song, "Before He Cheats," in which a scorned woman goes after her boyfriend's truck with a Louisville slugger. "I wouldn't recommend doing any property damage, though."

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