If you're lean and healthy and you want to stay that way, steering clear of burgers is a wise move. It's an even wiser move for those who are obese -- studies show that obese people are even more affected by burgers and other high-fat, high-carbohydrate foods.

In one study, 10 normal-weight folks and eight obese folks were fed an 1,800-calorie meal consisting of a burger, fries, cola, and apple pie. After two hours, blood tests showed that both groups had increased inflammatory and oxidative stress -- key factors in artery hardening, which leads to heart attack and stroke. Another hour later, the lean eaters' levels were back to normal. The obese group's numbers were still rising. The interesting twist is this: a high-fiber, fruit-based meal full of 1,800 calories had no such adverse effects.

This study, detailed in the March 2008 Reader's Digest, is small and therefore not conclusive. Still, we might learn a lesson from it: Ditch the greasy burgers, especially if you're above a normal weight range, and embrace fiber and fruit. Nothing new, is it? Consider it a friendly reminder.

If burgers are a must-have for you, check out these healthier varieties.

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