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Denise Richards has something to get off her chest: She's had three boob jobs.

Asked whether her breasts were real, Richards, 38, told Howard Stern on his SIRIUS radio show Thursday, "Um, natural on outside, on the inside they are not."

The actress - who kicks off a second season of her E! reality show, It's Complicated, June 7 -- said she got the surgery "a long time ago" after moving to Los Angeles to be an actress.

"I was 19, and my roommate had the best boobs ever, and she had just had hers done," she said with a laugh. "I was flat as a board, and I thought 'Whoa, you can just buy them' and stupidly had them done!"

After her first operation, she said her breasts looked "way too big for my body."

So she had a second one.

"The next guy put bigger ones in, and it was not good -- they were a D!" she said, adding that her doctor assumed she wanted to look more voluptuous because she's an actress.

The third procedure fixed everything.

Looking back, Richards said, "I was young and should have researched better. You know, it was a big mistake. Young girls, don't do it!"

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