Celebrity Sleep Secrets, and What You Can Learn From Them

Mariah Carey

Singer Carey, 39, takes sleeping to a new extreme. “I've got to sleep 15 hours to sing the way I want to,” she told Interview magazine in 2007. Most adults only need seven to nine hours a night. Sleeping for half the day would likely strike most doctors as strange. So would Carey's humidifier habit: “Literally, I’ll have 20 humidifiers around my bed,” she told V magazine. “Basically, it’s like sleeping in a steam room.” While the machines can help to moisten dry air and soothe sore throats, usually one will do.

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Photo: Mariahcarey.com