With obesity lowering and Americans (presumably) making healthier meal choices, McDonald's has chosen to change its menu options accordingly, the Associated Press reported.

While Burger King has decided to start selling healthier French fries, McDonald's will now begin offering a side of fruit, salad or vegetable as a substitute for fries. The fast food company said it had already offered the healthy substitution in other countries and will now start the practice in U.S. locations.

McDonald's announced the changes would be made in 30 to 50 percent of its 35,000 locations within the next three years and would be 100 percent implemented by 2020. CEO Don Thompson and his fast food chain made the announcement in New York City at the Clinton Global Initiative.

Thompson said McDonald's is looking into other healthy sides that will also appeal to customers, noting snacks like kiwi-on-a-stick and cups of corn could make their way into U.S. stores.

"What is it that customers will choose, and what will they eat?" Thompson said. "What we don't want to do is just put something on the menu and say, hey, we did it. We really want consumption."

McDonald's also stated it would work to advertise healthy eating to children through its Happy Meals. For example, carrots will come in a colorful bag and milk, water and juice will be promoted with Happy Meals, although parents can order a soda for their child if they want.

Center for Science in the Public Interest director of nutrition policy Margo Wootan was hesitant to praise the fast food chain for its changes. She added the changes are a good start and that others should follow McDonald's new Happy Meal model.

"The changes McDonald's are making make the food somewhat healthier. But I don't think a hamburger, some applies and fries is something I'd call healthy," she said.

McDonald's is certainly aware of the healthier trends growing as many studies show obesity rates finally on the way down. The fast food chain recently starting offering egg whites on breakfast sandwiches and began selling chicken wraps with lettuce and veggies.

Thompson said he paid special attention to the criticisms surrounding McDonald's heath initiatives for children.

"Others have said, 'McDonald's, don't advertise to kids,'" Thompson said. "We've always felt like, wow, if we had the impact that you think we have, why don't we leverage it to do something great for kids?"