Some say the key to turning back the clock is staying young at heart. And, of course, diet and exercise help, too. McDonald's (NYSE:MCD) is trying to key into those very sentiments by testing its "Go Active Meal" in Indiana.

According to The Washington Post and other news services on Wednesday, this adult-targeted Happy Meal will pass on the calories and fat that the chain is notorious for. Instead, it'll pack a salad, a pedometer (one of those gadgets that tells you how far you've walked), and a booklet from Oprah's own personal trainer.

There's a lot of appeal in this little marketing gimmick. Many of the adults who were raised on McDonald's Happy Meals should get a kick out of this whimsical and useful takeaway.

It targets the very adults who grew up on McDonaldLand burgers and fries, but decided if they kept it up, they might keep on gaining a bit too much weight. With the increasing media focus on America's obesity problem, not to mention the success of Subway's "eat fresh," low-fat campaign that lured many consumers away from traditional fast-food fare, McDonald's "supersized" reputation became downright unappetizing for many.

Other chains have announced healthy food initiatives, including old-school burger competitors Burger King and Wendy's (NYSE:WEN). Even Jack in the Box (NYSE:JBX) is in on the act, revamping its menu for a different kind of customer in a different kind of climate.

Even though the lawsuit blaming McDonald's for obesity was laughed out of court, the public's increasing health awareness is no laughing matter. If McDonald's can convince the public that wholesome foods, not just fat and grease, lie within those Golden Arches, it should fatten up its sales and regain the loyalty of what could have become a lost generation of calorie-conscious customers.

You can reach Alyce Lomax at .