Teen Mom star Amber Portwood says in the new Us Weekly (out now) she's "been chunky my whole life." That's a thing of the past: since giving birth to daughter Leah (with boyfriend Gary Shirley, 23) in November 2008, the MTV reality star has lost an impressive 65 pounds!
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"I was looking in the mirror and I thought, I don't like this. I'm only 20. I need to kick it into gear," the 5-foot-4 Indiana native, now 118 pounds, tells Us Weekly of her post-baby body.
How did she do it? Out with mac and cheese and sweets and in with lean meat, fruit and vegetables -- plus two-hour cardio and weight sessions four times a week. (The Krav Maga disciple is even gearing up for her first martial arts competition.)
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"The first time I tried on jeans after I lost weight, there were a size one," Portwood reveals. "I thought, there's no way. This is crazy!"
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"I'm more comfortable in my skin," she adds, noting that her beau Gary "really likes" her new shape. "Who wouldn't?"
