So many of my friends are on diets these days. If you're like them, you long for a healthy alternative when the lunch bell rings. Well, why not try McDonald's (NASDAQ:MCD)? No, I'm not kidding.

First, there was the introduction of all white meat Chicken McNuggets a year ago in the New York, New Jersey, and Connecticut areas. After some initial success, the change went national last September. McDonald's reported yesterday that sales of McNuggets are up 35% since the introduction of all white meat.

Next, there was "Real Life Choices," another NY-area program rolled out in January in which hungry customers can alter McDonald's classic menu to create low-carb, low-fat, or low-calorie meals.

Barely two weeks later, McDonald's announced that its "Go Active" adult version of the classic "Happy Meal" featuring a salad, drink, and pedometer will launch nationwide before year's end. And just days ago, Fool Alyce Lomax reported the Golden Arches would eliminate its signature "Super Size."

Now, McDonald's says it plans a low-carb menu item in its U.S. restaurants sometime in the next 60 days. Oh, and this just in: Cats and dogs have started living together en masse in suburban Cincinnati.

Seriously, I understand that there's pressure from competitors such as Wendy's (NYSE:WEN), Subway, and CKE Restaurants' (NYSE:CKR) Hardee's, which introduced the lettuce-wrapped burger for Atkins fans. And with McDonald's same-store sales up 13.9% for February, it's hard to argue with continuing the strategy of shifting menu items to meet customer demand.

But I will anyway, because I seriously doubt the added business comes from dieters. Instead, the new, slimmed-down McDonalds's appears to be an image makeover, from classic burger-and-fries joint to healthy fast-food destination. If so, I understand why.

A forthcoming documentary called "Super Size Me" lampoons McDonald's by showing the deleterious effects of an all-McDonald's diet. Mixing in some greens is bound to deliver some positive publicity. But don't expect it to last. "Healthy fast food," like "safe tobacco," isn't a credible message. Moreover, a healthful positioning moves McDonald's away from its core burgers-and-fries franchise.

I've been in the image-making business, and there comes a time when the price of PR is simply too high. For McDonald's, that happens when burgers shift fully into the background. That day doesn't appear too far off.

So, Ronald, please. Get back there and start flipping burgers again, okay?

Is McDonald's trying to be health-food outlet? If so, is it a good thing? What Atkins-approved item will McDonald's add to its menu? All this more at the McDonald's discussion board. Only on Fool.com.

Motley Fool contributor Tim Beyers doesn't own stock in any of the companies mentioned here and he isn't on a diet. Nah, he's in training for his family's upcoming St. Patrick's Day feast.