From PEOPLE Magazine Click to enlarge
HEIDI KLUM, 10 HRS.

CHECK OUT: HEIDI'S NEW BALANCE LINE ON AMAZON.COM

"I go to sleep pretty much when the children go to sleep! My husband has to come find me in one of their four beds and remind me that I'm still a wife too!"

SEE HER IN: ANN TAYLOR ADS

"I try to get eight hours, but it is usually six. Sunday is my day to catch up."

KATIE HOLMES, 6 HRS.

SEE HIM IN: THE LINCOLN LAWYER

"I'm not near as good the next day if I get less."

MATTHEW MCCONAUGHEY, 8½ HRS.

SEE HER IN: EVERYBODY LOVES WHALES "When I am not working, I catch up, which makes me happy!"

DREW BARRYMORE, 3 HRS.

JESSICA BIEL

SEE HER IN: NEW YEAR'S EVE

"I'm a very light sleeper, almost to the point of insomnia. I've tried counting sheep, but I'm really much more of a dog person."

SEE HER IN: NEW YEAR'S EVE

"I love to sleep. When I'm rested, I'm at my best."

HALLE BERRY, 9 HRS.

SEE HIM IN: NEW YEAR'S EVE

"I'm burning the candle at both ends, so it varies from night to night."

ZAC EFRON, 6 HRS.

SEE HER IN: X-MEN: FIRST CLASS

"Any less than six and I have to cover the mirrors in my house."

JENNIFER LAWRENCE, 8 HRS.

SEE HIM ON : AMC'S MAD MEN

"I like a solid 12-but not all at once. I tend to go 4 on and 4 off."

JON HAMM, 12 HRS.

SEE HER ON: NBC'S THE VOICE

"People spend money on beauty potions, but a good night's rest makes all the difference."

CHRISTINA AGUILERA, 8 HRS.

SEE HIM IN: REAL STEEL

"I'm lucky to get seven hours. I have a 10-year-old and a 5-year-old."

HUGH JACKMAN, 7 HRS.

SEE HER ON: THE ELLEN DEGENERES SHOW

"I'm usually asleep by 11 p.m. and up around 7:30 a.m. It's a lot!"

ELLEN DEGENERES, 8½ HRS.

SEE HER IN: SPY KIDS 4

"Luckily my daughter averages 12 hours, so we get a lot of sleep in our house-for now!"

JESSICA ALBA, 8 HRS.

HEAR HER ON: HER CD I REMEMBER ME

"One of the greatest luxuries is a solid eight hours every once in a while!"

JENNIFER HUDSON, 8 HRS.

Beyoncé Knowles

CURRENTLY: RECORDING HER NEXT CD

"I am a person who has a hard time shutting off my brain. But if you are active during your day, you will be so exhausted you can't help but fall asleep. Having peace, happiness and healthiness is my definition of beauty. And you can't have any of that without sleep."

SEE HIM IN: GREEN LANTERN

"I think about all the blinking I've done during the day and try to add it up in my mind."

RYAN REYNOLDS

SEE HER IN: NOW

"I get more sleep than the average human being."

AMANDA SEYFRIED, 10 HRS.

SEE HER ON: DESPERATE HOUSEWIVES

"Anytime I sleep less, I pay for it the next day."

EVA LONGORIA, 8 HRS.

SEE HER IN: SOMETHING BORROWED

"If I am not drinking enough water, I will wake up with sleep lines."

GINNIFER GOODWIN, 8 HRS.

SEE HER ON: TNT'S HAWTHORNE

"Once I had children, I got used to not sleeping much."

JADA PINKETT SMITH, 6 HRS.

SEE HIM IN: TRANSFORMERS: DARK OF THE MOON

"That's before the rescue dogs and three kids wake us."

PATRICK DEMPSEY, 6 HRS.