Sometimes, said fashion guru Tim Gunn, they don't know how to show it off, or even find clothes that fit.
"Once you've reached your goal, it's time to go shopping or at least alter your old clothing. ... My mantra about 'getting' fashion is silhouette, proportion and fit. When they are in balance, you'll look great in whatever you're wearing," he said.
When women are in a transitional phase, he suggests a wrap-style top or dress, which basically adjusts itself to changes in your body. (It's his must-have pick for all women, actually.)
He'd also steer people toward V necklines instead of a crewneck or boatneck. V necks lead one's eye up to the wearer's face, he explains, which can make a flattering line.
Pants often can be taken in to accommodate a smaller size because they have mostly straight seams, Gunn explains, but jackets and blazers are trickier for a tailor to fix if shoulder seams start to creep down the arm. Men especially have an issue with collars.
The least flattering look? Clothes that are baggy, said Gunn, the "Project Runway" mentor and soon-to-be host of the daytime talk show, "The Revolution."
Women and men are equally prone to hiding behind too-big garments, whether they've stuck to their weight-loss routine or not, because they think showing their shape will draw attention to their shape, he said, but the opposite is true.
"The more fabric there is, the more of you there is to look at."
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