Stars and Obsessive Compulsive Disorder
PHOTO: Lena Dunham arrives at the 36th Annual Los Angeles Film Critics Association Awards at InterContinental Hotel on January 15, 2011 in Century City, Calif.

Girl-of-the-moment Lena Dunham talks candidly about her battle with obsessive-compulsive disorder and anxiety in the Feb. 28 issue of Rolling Stone.

In the cover story, the 26-year-old creator and star of HBO's "Girls" says she took antidepressants in high school, and was obsessed with the number eight.

"I remember saying to my mom when I was little, 'I just had to imagine having sex with you eight times,'" she says in the magazine, "and she really took it in stride! She was like, 'Well, it's your imagination; it didn't really happen.'"

Dunham, who dons a black lacy bra peeking out from a revealing white tee on the magazine's cover, also addresses the quote made famous by her character, Hannah Horvath, in the show's pilot.

"It's funny to me that I'm writing a show that people consider to be the voice of twentysomething people," she says. "Because I don't feel that connected to it all the time."

"Some of my anxieties might be solved by a better awareness of what's actually befalling this planet and what makes everything run and what's come before us," she says. "But it overwhelms me too much. It makes me want to take a nap." She takes a breath. "And in that respect, I really relate to people in my generation."

If it seems as though OCD and celebrity go hand-in-hand, there's a reason -- so many celebrities have admitted to having the condition. Click through to see some of them.

Charlize Theron

New mother Charlize Theron may have a tougher time than other new moms adjusting to her first child. That's because she's admitted to suffering from obsessive-compulsive disorder or OCD.

"I have OCD, which is not fun," she told Australian radio show Kyle and Jackie O. "I have to be incredibly tidy and organized or it messes with my mind and switches off on me."

Babies, especially once they reach toddler-hood, aren't exactly known for their neatness. The Oscar-winning actress announced that she is the "proud mom of a healthy baby boy named Jackson" in March 2012. This is the first child for the 36-year-old actress who has been single since her split from actor Stuart Townsend in 2010.

For parents with OCD, having children can actually make symptoms worse. "OCD symptoms tend to latch on to things that are most important to us, so parents with OCD may have doubts about their abilities or intrusive thoughts about their child's safety or hurting their child," Stephen Whiteside, a psychologist at the Mayo Clinic in Rochester, Minn., who specializes in anxiety disorders including OCD, told ABCNews.com.

OCD is an anxiety disorder that at its basic level is a fear of one's thoughts, whether it's a fear of messiness, germs or something else. To relieve the anxiety associated with such intrusive thoughts, an obsessive-compulsive will feel compelled to behave in a certain way, such as cleaning out their cabinets before going to sleep or checking and rechecking their child.

Whiteside has heard anecdotes of OCD patients actually improving once they became parents. "It's certainly possible that when you have something that is of greater concern to you -- you're not just taking care of yourself but a baby -- those emotions can overwhelm the OCD and motivate you to do the things to get better. The best treatment is exposure or facing your fears," Whiteside said.

That's what happened to Julianne Moore, who scrapped her daily routine of leaving her apartment at exactly the same time and pacing her walk so that she only got green lights, after having children Caleb and Liv. "Having two young children means you drop all that sort of rubbish!" Moore told UK's Guardian.

Moore admitted she's still "fanatical about straightening furniture and lining stuff up, but I'm much more laid back than I used to be!"

Theron also struggles when things are out of order. "I have a problem with cabinets being messy and people just shoving things in and closing the door. I will lie in bed and not be able to sleep because I'll say to myself: 'I think I saw something in that cabinet that just shouldn't be there,'" she was quoted saying in London's Daily Mail.

Comparing herself to the character she played in "Young Adult," she told the Australian radio show, "I am not dirty at all, I'm actually the opposite."

Whiteside's advice to her and other new parents with OCD: "Try to put things in perspective, reminding yourself that you're going to do a much better job as a parent if you leave things messy and spend time with your child than being perfect."

He said, "It might be uncomfortable at first, but the feeling gradually goes away, and it should get easier."

Julianne Moore

In 2008, the "Game Change" actress told UK's Guardian that her OCD tendencies draw her to dark, emotional characters. She talked about doing the "lucky walk," leaving the house at a certain time and pace so that she would face more green lights than red.

"Those are the indulgences you can have before you have children," she said. "Now I don't have time to obsess. All that stuff about, 'I need to go this certain way and do that,' was an indulgence of my youth."

Megan Fox

Megan Fox may get down and dirty in her movies, but in real life she likes things clean, very clean. In 2010, the bombshell actress and model admitted that she has OCD.

"This is a sickness, I have an illness, this is not OK anymore," Fox told Allure magazine. Her problem: public toilets and restaurant silverware. The "Transformers" star told Allure that she won't use toilets without seat covers: "I'm never doing that again. Every time someone uses a bathroom and they flush, all the bacteria is shot into the air."

She also opened up about her feelings on restaurant silverware: "Putting my mouth where a million other mouths have been, just knowing all the bacteria that you carry in your mouth? Ucch!"

Jessica Alba

Jessica Alba has said her OCD came out of a need to have control over her life.

"I used to unplug every single appliance in my house. Or I'd double-check every door in my house to make sure it was locked at night," she told CosmoGirl last year. "It was like a panic come over me and I had to do something, and once I did it, I was OK. ... It was really me needing to control something."

"I can be a little obsessive compulsive about things, but that just means that when I do things, I do them proficiently and I do them to the best of my ability," the "Fantastic Four" star was quoted saying on British Web site iVillage. "I think a lot of actors have OCD. I think it's part of being creative, whether your outlet is acting or science or math. Whatever it is, it takes some sort of drive to get anywhere."

Cameron Diaz

Diaz will open doors with her elbows just to avoid touching the germ-infested doorknobs. The sexy star of "Bad Teacher" and "Shrek" has admitted to cleaning the doorknobs of her Los Angeles home so much that the original paint has faded on them. She has also said she washes her hands "many times" each day.

But perhaps her obsession has diminished somewhat. In May 2007, she told a reporter, "I think I've made my peace with it."

Diaz's ex, Justin Timberlake, has also copped to having OCD. He was quoted by the Web site Collider.com as saying, "I have OCD mixed with ADD (attention deficit disorder). You try living with that. It's complicated."

Howard Stern

Stern has been outspoken about his own struggles with OCD. In his 1995 book "Miss America," he described how he could not turn on the car radio without tapping the dial a certain number of times with his right hand.

"The ... rituals were my distraction,'' he wrote. "When I was in college and nervous about entering the world of broadcasting and earning a living, the pressure was enormous. ... As a defense mechanism, my brain had set up an elaborate maze of rituals that kept me from confronting my fear."

He said once he made the connection, he instantly stopped his compulsive behavior and now practices transcendental meditation.

Leonardo DiCaprio

The "Titanic" actor once played another famous sufferer of OCD, Howard Hughes. In fact, while playing the role, DiCaprio's got back in touch with his own childhood obsession: sidewalks.

"I remember as a child, stepping on cracks on the way to school and having to walk back a block and step on that same crack or that gum stain," DiCaprio told About.com at the time the Hughes biopic "The Aviator" was released.

"Let's just say it took me a while to get to set, having to step on tons of things," he said, laughing.

David Beckham

Beckham likes to keep his shirts in order, lining them up in the closet according to color. So do a lot of people, you say. How about matching all the food in your refrigerator? Apparently, the soccer star likes order in his fridge as well, which is why he has three.

"Food in one, salad in another and drinks in the third," his wife Victoria Beckham said, according to the Daily Mail. "In the drinks one, everything is symmetrical. If there's three cans of Diet Coke, he'd throw one away rather than having three -- because it has to be an even number."

"He's got that obsessive-compulsive thing where everything has to match," she said.

Billy Bob Thornton

The eccentric actor-turned-musician has talked about his OCD in 2004 with "Dateline"'s Ann Curry, saying it grew out of a difficult childhood filled with abuse.

One of his compulsions is "constantly doing mathematics," he said. "Certain numbers represent certain people. And I can't use that number in a certain circumstance. And then I have to use it in another circumstance."

"It exhausts you," he said about his disorder.

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