"Skin-nee!" Trading compliments with Star Jones Reynolds on the red carpet, Winfrey showed off her newly svelte look, stunning proof of her triumph over a decades-long battle of the bulge. (At her heaviest, the 5'6 ½" Winfrey weighed 237 lbs.)

"After many years of my weight going up and down, I realized that the commitment to do well and to be well is a lifetime of choices that you make daily," she wrote in the February issue of O magazine. That includes swearing off fad diets—remember Optifast?—for a sensible eating plan and making peace with workouts. (See box.)

"Don't get me wrong," she wrote. "You won't see me jumping up and down, going, 'Oh, jeez, exercise is great,' but I no longer dread it." It also means dressing her size-10 body in figure-revealing fashions, like the Celine suit she wore to kick off her show's 19th season, and couture fashions from Valentino and Ferre.

Last month, still aiming to reach her "safe zone," in the 150s, she recruited four Oprah staffers for a 12-week "boot camp" program for moral support. But she did break routine on one day in particular. "I work out every day," she said, "but I thought, 'Doggonit, it's the Oscars. I'm going to take the day off.'"

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