14/08/2014 16:40 BST | Updated 20/05/2015 10:12 BST

Model Carol Alt On Being In The Industry Before Photoshop - And The Diet She's Stuck To For 20 Years

American model Carol Alt knows her stuff when it comes to striking a pose for magazine covers.

The 51-year-old fronted the Sports Illustrated '50 Years Of Beautiful' edition for the 50th anniversary issue - and it wasn't the first time she's made the magazine's cover spot. (Alt was the face of the 25th anniversary issue too.)

What's her secret to being so successful in the modelling industry? Her strict diet.

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In an interview with Refinery 29, Alt revealed she's been on a raw diet since 1996 and has "never looked back." Yes, that's a lot of carrot sticks. Why has she stuck to it for so long?

"You soar; your energy changes; how you feel about your body and how you feel in your own skin changes," Alt told the site.

But aside from sharing her eating habits, Alt also spoke about the dramatic changes in photoshoots since Photoshop was introduced.

"It was called airbrushing, but it left a shadow," she said. "So, if they wanted to make me thinner in a picture and they airbrushed it, you would see the shadow. Everybody knew, so it was not sneaky at all."

And now? Alt prefers a no retouching policy.

"It's been that way throughout my entire career because we didn't have this kind of retouching way back when."

Models today don't know how lucky they are.

Source: Refinery 29