Shia LaBeouf: I Get My Sense of Humor From Watching Parents “Have Sex”

Where does Transformers star Shia LaBeouf get his wicked sense of humor?

"My humor came from seeing my parents have sex, smoke weed, my mom being naked — just weird hippie stuff, twisted R-rated humor," he tells the latest issue of Parade magazine. LaBeouf — who once called his mom "the sexiest woman I know" — admits: "The good actors are all screwed up.

See what Shia — and other stars — look like as Lego characters!

"They're all in pain. It's a profession of bottom-feeders and heartbroken people," he goes on. The 23-year-old says that when he's feeling insecure, he stops his bike on the side of a busy road to see if people passing by recognize him (he's afraid they won't).

Check out more photos of stars on bikes.

"Actors live dependent on being validated by other people's opinions. I don't understand what it is I do that people want. I don't know what an actor does. I have no credentials. I don't know what I'm doing. To my mind, talent doesn't really exist. Talent is like a card player's luck. It is motivation, ambition, and luck. It's just a drive to be the best. I think acting is a con game." LaBeouf admits he doesn't "handle fame well."

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"Most actors on most days don't think they're worthy," he goes on. "I have no idea where this insecurity comes from, but it's a God-sized hole. If I knew, I'd fill it, and I'd be on my way." LaBeouf goes on: "Sometimes I feel I'm living a meaningless life and I get frightened. I know I'm one of the luckiest dudes in America right now. I have a great house. My parents don't have to work. I've got money. I'm famous. But it could all change, man. It could go away. You never know."

The actor also opens about his spring 2007 split from first love China Brezner, a producer's daughter he met on the set of The Greatest Game Ever Played.

Check out more ugly Hollywood splits.

"Maybe it was career pressure…. Maybe I chose work. Every man has those feelings of escape and survival," he says. "I know you shouldn't be that way. I'm trying to understand it and find the answers. I don't have them now. Why did the love of my life and I break up Man, I have no idea. What was that all about? I have no answers to anything. None."

"Why am I an alcoholic?" the actor, who was arrested for DUI in July 2008 (charges were dropped), goes on. "I haven't a —- clue! What is life about? I don't know."

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