Chicago ? Striving for a healthier image in the age of obesity, McDonald’s is rolling out new Happy Meals specially for adults with salad, bottled water and pedometers — and coming soon for the children, fresh fruit instead of fries.

Now it’s up to the patrons of Big Macs and fries to decide how big an appetite they have for a healthier McDonald’s, which unveiled its latest low-fat offerings Thursday as part of a new marketing blitz.

A target of obesity lawsuits and a magnet for criticism that fast food is bad for you, McDonald’s Corp. is simply trying to meet health issues head-on and show that it, like many of its customers, has become more diet-conscious. Top executives announced the new campaign in Washington, where U.S. Health and Human Services Secretary Tommy Thompson applauded McDonald’s for promoting balanced eating and exercise.

The new “Go Active!” adult Happy Meals will be available in all 13,600 U.S. McDonald’s on May 6, accompanied by brochures offering some gentle exercise advice.

“We want to help adults achieve the right balance between their daily calorie intake and physical activity, and to help children adopt active, balanced lifestyle habits early on,” said Mike Roberts, president of McDonald’s U.S. business.

The introduction of adult Happy Meals is just one in a series of moves by McDonald’s, which introduced white-meat chicken nuggets late last year and is phasing out super-sizing.

As part of the campaign, the company said that in June it would roll out healthier choices in its Happy Meals for children nationwide, such as the option to substitute apple slices and juice for fries and soft drink.

It also will distribute brochures telling customers how to modify their McDonald’s orders for lower fat, calories and carbohydrates.

Also new: lowfat salad dressing, a fourth variety of salad, and providing nutrition information on Happy Meal packages starting in test markets.

Michael Roberts, president of McDonald's U.S. business, announces the company's new adult Happy Meals. Roberts talked Thursday about the meals.