Trisha Yearwood shows off her stunning new shape – she lost 30 lbs. in four months! – and shares the secrets to her guilt-free diet in this week's issue of PEOPLE. When she learned her husband, Garth Brooks, would be singing at the April 7 Academy of Country Music Awards alongside his hero George Strait, Yearwood, 48, began searching for "arm candy" attire to wear to the Las Vegas event. That's when she spied that dress – a formfitting Stella McCartney column that she'd first admired on Kate Winslet in 2011. "I'd been working hard and losing inches, but I wondered, 'Can I fit into that?'" Yearwood tells PEOPLE. The answer was a jaw-dropping yes. "It was tight!" she says, but "I felt confident. It was a wow dress."
"My butt and my waist are smaller, and I like seeing that in the mirror!" says the 5'9" Grammy winner. "But I also feel great." So good, in fact, that on her flight back to the home near Tulsa she shares with Brooks, 51, "we got on the plane, the sweats were on, and I had an In-N-Out burger with fries and two dark chocolate Reese's cups!" she says. In years past, she adds, "if I did that, I would have said, 'You just screwed up, so might as well go out and have 20 cheeseburgers,' and I would. [This time] I got on my treadmill the next day, I ate well and I didn't do any damage. That's what real people do."
Finding that balance between instilling healthy habits and occasionally dipping into those not-so-healthy ones has always been a struggle for Yearwood. "I don't think you can name one diet I haven't done. I'm that girl who buys every magazine where somebody's lost 30 lbs. But I guess a part of me didn't want to hear that it's just really hard work!" the singer admits. "I'd been doing circuit training and Pilates for years, but I was not consistent with food. I'm not a disciplined person. I was indulging all the time."
Her turning point came after a Habitat for Humanity trip to Haiti last November, which gave Yearwood a fresh perspective on life – and her fitness level. "It was 100 degrees, I'm wearing work boots and putting a roof on a house, and I just thought, 'Man, I want to be lighter,'" says Yearwood, who then overhauled her diet in January. "I don't have it all figured out. But right now I'm having more days that I win the battle than days I lose." Her winning streak started off slowly, first by planning all her meals. "I try to cook all my food for the week and I actually write out a menu," she says. "I designed my own plan that's low-fat, low-sugar 90 percent of the time."
She's getting her family on board, too. "Garth says, 'I always lose weight when my wife is on a diet!'" says Yearwood. Lately, with weekly basketball games against Yearwood and her healthy influence, "he's probably lost 20 lbs.," she says. "He doesn't really weigh himself. He just knows if his pants fit." His support is much more than a sympathy slim-down. "He makes me feel great no matter what the scales say," she says. "If I lose weight, he says, 'I love you at this weight. And the only other weight I love you at is whatever other weight you are.'"
Yearwood is determined not to give up on herself this time. "This is not some crazy fad diet. It's a lifelong change. I've seen a lot of 'before and afters' and this is really a 'during.' I'm not done. I don't know what my goal weight is, but I'm proud of myself. I'm really happy where I am."
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