How Christie Keeps Her Supermodel Hair at 59

Christie Brinkley recently sat down with ET to talk about her new Hair2Wear collection of clip-on extensions, which she reveals is a big part of what keeps her still looking undeniably amazing at 59 years old.

"A healthy diet, exercise and Hair2Wear," she said about the secret to her youthful looks. "As you age, your hair thins out. So it's one of the things we notice about ourselves is, 'What happened to all my luxurious hair?' And with my new collection, even if you have a full head of hair, it will enhance your hair and make you feel just so great."

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And Christie proved she practices what she preaches, wearing her own line of hair extensions mixed in with her own natural hair during the interview.

"I'm very proud of this," she stressed about her new collection. "I think five years ago, women used to think, 'Oh that's so fake,' you know, to put in hair. Fake? No, it's time saving. It's giving me what really matters. Why should I spend time in the bathroom, trying to tame all of this, when I can snap something in and get to what really matters?"

Christie also happily talked about the milestone of turning 60 next year.

"Well I can tell you that one of the best things about turning 60 in February is that Sports Illustrated is turning 50, so it doesn't make me feel quite that old," she laughed.

Christie, who famously covered the iconic magazine three times in a row from 1979-1981, will be appearing in the new book Sports Illustrated Swimsuit: 50 Years of Beautiful (out Oct. 22), which tells the inside story of the Sports Illustrated Swimsuit Issueand how what began as an eight-page travel piece has emerged as one of the most star-making and hotly anticipated events of the year, with an audience of more than 70 million.

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"I am so grateful to Sports Illustrated for really introducing me to America, and giving me a brand name," Christie said. "It was amazing. Before Sports Illustrated, I was a starving artist in Paris. .... It was just crazy."

Check out the video to see Christie personally demonstrate her new collection on two hair models, and hear the only bad thing she can think of when it comes to turning 60.

Click here for more information on Christie's new Hair2Wear collection, and click here to check out her Facebook page.