A healthy rule of thumb is to keep your meal around 500 calories, says Katherine Brooking, a registered dietitian and cofounder of AppforHealth.com, but that can be hard with big juicy burgers and lots of fixings. You're generally safe, though, with the plainest, smallest burger available.
"If you stick with a plain single patty, you may even be able to have a small order of fries," she says. All the major drive-throughs have similar plain offerings, but Wendy's Jr. Hamburger - at just 230 calories, 8 grams of fat (3 grams saturated), and 470 milligrams of sodium - is the least nutritionally offensive.
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