Charlize Theron knows "a lot" of sex addicts.

The 'Burning Plain' actress understands the pain and confusion that surround sexual obsessions, and the way they tear families apart.

Charlize Theron is not "an exhibitionist".

The 'Burning Plain' actress - who appears naked in the first scene of the movie, and has also stripped off in 'Monster' and 'The Devil's Advocate' - insists she only flashes flesh on film if it is integral to the storyline.

Charlize Theron often feels like she has taken drugs. The "Burning Plain" actress constantly feels anxious about things she has said, and likens the worry to how people feel the day after they've taken drugs.

She revealed to America's Vogue magazine: "People tell me that drugs makes you feel superhuman and you'll say anything. Then, when you come down, all of a sudden you have guilt. But I have that feeling innately, even without the drugs."

Will Smith punched Charlize Theron in the face when they first worked together. The actor was preparing to portray legendary boxer Muhammad Ali when he starred alongside the blonde beauty in 2000's "The Legend of Bagger Vance" - and got carried away showing off his fighting skills.

Charlize said: "The first time I worked with him he punched me in the face. He was training for 'Ali.' I encouraged him to show me a couple of moves. I was completely knocked out!"

Charlize Theron thinks Tom Hanks has a sexy butt. The Oscar-winning actress - who was directed by Tom in her breakthrough movie "That Thing You Do!" in 1996 - is impressed with the 52-year-old star's behind and can't stop gushing about it.

She said: "He has a really good a*s. A really, really good butt."