Fed up with feeling sad, Leigh Mount detoxed her diet, shed 171 pounds and discovered the joy of living light.

By As told to Hannah Campbell
Updated June 10, 2014

ididit-beforeLeigh Mount
Friendswood, Texas
Age: 30
Height: 5'5
Before: 318 lb.
Dress size: 28
When I moved into my first apartment on my own in 2008, I was in a terrible place emotionally. Unhappy with my body and my life, I turned to food, numbing myself with frequent Taco Bell binges, the ever-present stockpile of cheesy snacks in my pantry and calorie-dense cocktails. By July 2011, my weight had ballooned to an unbelievable 318 pounds, and I had grown more miserable than ever. At one point, my stepmom was so concerned that she treated me to a salon day to try to snap me out of my funk. After being pampered for hours, I realized how much I missed taking care of myself. That's when I decided it was finally time to get serious about slimming down.

Bye-bye, fake food
Within a month, I joined my local weight-loss center. When I reviewed the first week's meal plan, I was pleasantly surprised: The three meals and two snacks a day offered me more real food for far fewer calories than I was used to. And because there were filling options, like spinach quiche and chicken stir-fry, I never felt hungry. I began to eat clean and almost immediately lost 18 pounds, and the heartburn that had plagued me since my teens disappeared.

Hello, happier me
ididitAfter: 147 lb.
Dress size: 4
Total lost: 171 lb.
Sizes lost: 12

Felix Sanchez I quickly found my way around the kitchen, and two months later I had knocked off another 32 pounds. My energy level soared: While I had once been a slave to the snooze button, I started waking up at 5:20 each morning, excited to start the day. And I was more active, taking two- to three-mile walks around my neighborhood. Slowly but steadily, the pounds melted away.

By June 2013, almost two years after starting my transformation, I had dropped more than half my weight; I was down to 150 pounds. In the year since, my daily walks have transitioned into runs, and I even completed my first half marathon. There was a time when the notion of running was laughable to me, but after coming so far, I finally feel like my life has no limits.

Her Stay-Slim Tool Kit
For Leigh, healthy living is about the details. Find out what keeps her going forward, and score more tested tips on Pinterest.

Sweet Escape:
When I crave something a little indulgent, I have a South Beach Diet whipped peanut butter bar—it tastes almost exactly like fudge. At 100 calories, it's a perfect midmorning or afternoon treat.

Magic Kicks:
My boyfriend got me Brooks PureConnect 3 running shoes. They're so light, I feel like they give me wings!

Up Running Song:
I have "Happy" by Pharrell Williams on my workout playlist. When it comes on around mile six, I feel like I'm in total butt-kicking mode and can't help running down the street clapping, smiling and lip-synching.

Throwback Toner:
Hula-Hooping is a favorite. It's fun and never feels like exercise. I keep one in my yard for when I get the urge to move!

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