She looks amazing!!  Good for her.  Here's how she dropped the weight, as she told "Shape" magazine -

"It was before my 21st birthday. I had walking pneumonia, couldn't breathe, and felt totally fatigued. I remember thinking, 'I'm in my prime, I should be happy and fit.' That was the moment when I decided that changes needed to be made."

Out went calorie-laden snacks (Smartfood popcorn became a crunchy treat). She started controlling her portions and stopped eating two hours before bed. Working out was a challenge, but she gradually went from walking to hiking. Strength training and Zumba became passions.

Check out the pictures here!