From PEOPLE Magazine Click to enlarge
JANET JACKSON

Before heading out to promote her CD 20 Y.O., the singer-actress went from plus size (180 lbs.) to hard body (120 lbs.) in just four months. To shed the 60 lbs. she piled on for a movie role that never materialized, Jackson, 40, turned to the pros. Nutritionist David Allen allowed her five small meals a day. "I said, 'I'm taking over and you're doing this,'" he says. Trainer Tony Martinez devised a punishing regimen of basketball, boxing and hanging ab workouts, where she would slowly raise her legs while suspended from arm slings. "She hates to work out," he says. But when she does, "she's intense."

LOST 6O LBS.!

SEPTEMBER 2005
JUNE 2006

DELTA BURKE

After years of seesawing weight, Burke, 50, has slimmed down and is back on TV in a recurring role on Boston Legal. The actress, who has diabetes and still helms a line of plus-size clothes, is "a big believer in portion sizes and walking," says her rep.

JULY 2005
OCTOBER 2006

SHANNA MOAKLER

"The thing about dancing is, you're having so much fun, you don't realize you're sweating and moving every muscle," says Moakler, 31, who lost 12 lbs. on Dancing with the Stars. During her "stressful" split from Travis Barker, toning up "made me feel good about myself," she says. "It was a boost."

DANCED OFF 12 LBS.!

APRIL 2005
OCTOBER 2006

FOREST WHITAKER

To play Idi Amin in The Last King of Scotland, Whitaker, 45, put on a reported 70 lbs. After the film wrapped, the actor said he "got serious about diet and exercising," including hiking and martial arts. By King's premiere, his efforts had paid off.

SEPTEMBER 2005
NOVEMBER 2006

KELLY OSBOURNE

Since emerging from rehab (for depression) in June 2005, Osbourne, 22, shed 24 lbs. The rock heiress credits moving away from home and "getting myself together and mentally healthy," she says. "I stopped doing drugs and drinking. The weight literally just dropped off."

LOST 24 LBS.

MAY 2005
AUGUST 2006

TIA CARRERE

Weeks after giving birth in September 2005, Carrere, 40, joined Dancing with the Stars and soon hoofed off 25 lbs. She also subscribed to the NutriFit system, which delivered meals and snacks. Dancing viewers saw "a progression," she says. "It wasn't all of a sudden I was stick-thin after having a child."

LOST THE BABY WEIGHT

DECEMBER 2005
JUNE 2006

JOSH PECK

Once dubbed Pudge Master Flex, the star of Nickelodeon's Drake & Josh, 20, dropped 110 lbs. in 18 months by working out with a trainer and changing his eating habits. "It's my responsibility as a role model to... young people," he said recently.

APRIL 2004
MARCH 2006