Look Great, Feel Good in 2013

Guess the Celeb Get-Fit Tip

From going gluten-free to six-hour workouts, see if you know how these stars stay in shape

  • A gluten-free diet is the key to this starlet's svelte shape:

CREDIT: Chelsea Lauren / WireImage

Published: Monday December 17, 2012 03:00 PM EST By: Kiran Hefa

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Q: 1 of 6

Correct Answer: Miley Cyrus

After showing off a significantly slimmer frame in April, Cyrus revealed it was an allergy – not vanity – that led to her weight loss. "For everyone calling me anorexic I have a gluten and lactose allergy," she Tweeted, later encouraging her fans to follow her lead. "Everyone should try no gluten for a week," Cyrus wrote. "The change in your skin, [physical] and mental health is amazing! U won't go back!"