May 20, 2010 -- Megan Fox may get down and dirty in her movies, but in real life she likes things clean, very clean.
The bombshell actress and model admitted this week that she has an OCD, or obsessive-compulsive disorder.
"This is a sickness, I have an illness, this is not OK anymore," Fox told the latest issue of 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!"
Fox, 24, is the latest celebrity to confess she suffers from OCD. 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.
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 avoiding touching doorknobs.
Stephen Whiteside, a psychologist at the Mayo Clinc in Rochester, Minn., who specializes in anxiety disorders including OCD, said there's no research to show that celebrities are particularly predisposed to OCD.
But he said the characteristics of OCD, which include checking, frequent washing and being extremely organized, could be helpful to a person if utilized on a more "typical level."
"It would make sense that people with these types of traits can be highly successful," he told ABCNews.com. "And celebrities are highly successful people."
Whiteside said the term OCD is often misused, but it's a condition many people can relate to. Some of us wash our hands even when we don't need to or double check the lock on a door even though we know it's already locked. For many people, these are mild disruptions in their day; for others, OCD can completely put their lives on hold.
Clearly, many of the celebrities, including Alec Baldwin and Jennifer Love Hewitt, who have admitted to having OCD have managed to work around their disorder in order to lead successful lives. With more celebrities going public with their OCD, Whiteside said he hopes the stigma of what was once called the "hidden epidemic" can diminish and more people will seek treatment.
On the next page, read about some other celebrities with OCD:
Obsession: Messy cabinets
"I actually have a serious problem -- obsessive compulsive disorder," the Oscar-winning actress was quoted saying in London's Daily Mail. "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.'"
Mandel, the host of "Deal or No Deal," is coming clean about his OCD in "Here's the Deal: Don't Touch Me," a revealing memoir due out in November. The stand-up comedian has a fear of dirt and germs and won't shake hands with anyone. He even keeps his head shaved because it helps him feel cleaner.
Mandel talked publicly for the first time about his condition -- he also suffers from attention deficit disorder - on "The Howard Stern Show" in 2006. Mandel joked that his condition even prevented him from cheating on his wife for 20 years, because he was too afraid to make any moves on the models who appear on "Deal."
Obsession: His own fears
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.
The basic treatment for OCD involves exposure to one's thoughts, then preventing the response or compulsive behavior. Whiteside said severe OCD sufferers will require the help of a therapist. Others can take a more mindfulness approach, like Stern, and simply allow their thoughts to surface and not react to it, he said.
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.
Diaz will open doors with her elbows just to avoid touching the germ-infested doorknobs.
The sexy star of "Shrek" and "Charlie's Angels" 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."
Whiteside said OCD and ADD or ADHD (attention deficit hyperactivity disorder) often go together. He said OCD symptoms that present early in childhood, particularly for boys, are likely to be associated with ADHD and tics.
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.
Obsession: Perfectionism and control
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."
Like Whiteside, she said she believes that her OCD has actually made her and other actors more successful in Hollywood.
"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."