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Catherine Zeta-Jonesrouge - Known for her beautiful smile, this superstar is said to brush her teeth with a strawberry paste. She claims that it keeps her teeth white as she gets older.

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David Beckham - The famed soccer player has a type of OCD where everything has to be in even numbers or in pairs. This includes socks or even soft drinks in the fridge, and odd ones will get thrown away. He also has three fridges: one for food, a second for salad, and a third for drinks. 

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Elon Musk - The genius that has dedicated his projects to the health of the world didn’t used to consider his own health, as he would guzzle eight cans of Diet Coke and two cups of coffee every day. Thankfully, it’s said he’s kicked the caffeine bug.

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James McAvoy - The Scottish actor is known for saying “white rabbit” to the first person that he sees on the first day of each month.

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Mark Zuckerberg - The Facebook founder reportedly wears the same t-shirt everyday to avoid wasting precious time deciding on an outfit. Whatever happened to dress for success?

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Cindy Crawford - The model sprays her face with a mix of whole milk and mineral water, which apparently works as an exfoliant.

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Mariah Carey -

One of this diva’s strangest habits includes eating exclusively purple foods for three days of the week.

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Johnny Depp - A man of many talents and personalities on-screen, Depp is known for collecting Barbies in his free time! He told Jimmy Kimmel that he started off using the dolls to test out some of his famous movie characters by doing voices with the dolls and playing with his daughter.

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Jennifer Aniston -

To protect herself from bad luck, the actress will only enter a plane with her right foot, and she’ll tap the outside of the plane before boarding every flight.

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Simon Cowell - The famous judge’s favorite hobby is climbing trees. He says he climbs trees daily, and that it’s a ritual for him. Perhaps going up and down really levels him.

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Bill Gates - Exactly seven hours of sleep, no more and no less, is the key to Bill Gates’ routine.

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Cameron Diaz - The actress once had an OCD-induced tendency to open doors only using her elbows to avoid touching the germ-infested door knobs.

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Jessica Simpson - She’s reportedly never tried cigarettes, but apparently this star loves nicotine gum.

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Tom Cruise - The secret to this star’s handsome looks? Bird feces. Known as the Geisha Facial, this Japanese beauty treatment called Uguisu no fun (nightingale feces) was first popularized in Hollywood by Victoria Beckham.

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Eminem - The rapper requires a darkness like the inside of a coffin when he sleeps, and when he’s travelling he ensures that the hotel staff completely black out the windows.

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Katy Perry - This smiley star brushes her teeth six times a day and carries several brushes with her at all times.

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Paris Hilton - This superstar is obsessed with making a wish at exactly 11:11, and she let her Twitter followers know every few days from back in 2009 extending all the way to December of 2017.

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Kit Harington - While his character in 'Game of Thrones' may be comfortable travelling with a sword, Harington needs only his lucky pen, which he’s had since he was little, on his adventures. He also has to touch the outside of a plane three times before he gets in.

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Britney Spears - The Princess of Pop has a common nervous habit: biting her nails.

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Stephen King - This famous author has managed to keep his health, despite the fact that he eats a slice of cheesecake everyday before he starts writing.

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Arianna Huffington - The co-founder of The Huffington Post doesn’t allow any electronics in her room. She acknowledges that there is a time and place for technology and the vast information vortex of the internet.

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Pamela Anderson - The blonde bombshell never looks in mirrors! She has a phobia called eisoptrophobia, which is a persistent fear of looking at reflective objects. She also never watches herself on TV.

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Teri Hatcher - The 'Desperate Housewives' star likes to run herself a hot bath and pour a glass of wine, not for herself, but right into the water. It supposedly softens the skin.

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Demi Moore - This timeless beauty queen has a secret that most wouldn’t dare try… to detox, she uses the age-old and largely abandoned technique of leeches.

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Megan Fox - To soothe her nerves on a flight, the actress plays Britney Spears. She explained, "I know for a fact it's not in my destiny to die listening to a Britney Spears album, so I always put that on in my (headphones) when I'm flying because I know it wont crash if I've got Britney on."

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Kate Hudson - According to HuffPost, the actress wakes up between 6:30 am and 7:30 am, but always snoozes for 15 minutes. We can relate! 

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Wayne Rooney - This football star is known for turning on the vacuum or hairdryer when he goes to bed, since he can’t sleep without the noise.

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Halle Berry - The stunning actress has a bad habit of biting her lips, and apparently can’t go out without some sort of moisture, balm, or color.

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Christian Bale -

Unlike most people, the actor seeks out superstitions daily in order to challenge them. He enjoys walking under ladders, and his favorite number is 13.

See also: Celebrities who died with major secrets 

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