McDonald's will be serving healthy Happy Meals in the U.S. come September, as the world's largest hamburger fast food chain announced Tuesday that it will include a fruit or vegetable in the familiar food box for kids.

"Now is a great time for us to be able to do something like this," Jan Fields, president of McDonald's announced on ABC's "Good Morning America." "We think both parents and children are going to absolutely love the changes that we're making."

While price of the Happy Meal will remain the same, expect the portion size of French fries to be reduced from 2.4 ounces of potatoes to 1.1.

The reduction will make room for seasonal fruit and vegetables, including apple slices, carrots, pineapple slices or mandarin oranges, according to Fields.

McDonald's has taken several stabs at revamping its Happy Meal options. In 2004, the chain added the option of 1 percent milk to the rest of the meal (which included soda, a choice of hamburger, cheeseburger or chicken nuggets, and fries). In 2006, children had the option of choosing apple slices served with low-fat caramel dip instead of French fries.

The new Happy Meal will leave the sweet tooth to the soda, if ordered, as the caramel dip will be eliminated for good.

It is expected that some 14,000 McDonald's chains will complete the healthy transition by April 2012.