Teacher loses 60 pounds eating McDonald's for breakfast, lunch and dinner

COLUMBIA, SC -- After losing nearly 60 pounds eating nothing but McDonald's, an Iowa high school science teacher says he has learned that it's not where you eat, but what you eat that's important.

As part of a science experiment in his classroom, John Cisna ate McDonald's for every meal for three straight months. The challenge came after his students asked whether it was possible for a person to become better off eating nothing but McDonald's for breakfast, lunch, and dinner for 90 days.

Cisna adhered to a 2,000 calorie diet, followed the FDA's recommended nutritional guidelines, and walked 45 minutes 4-5 days a week, according to ABC affiliate WOLO-TV.

"This is what is astounding," Cisna said, "after 90 days I lost 37 pounds, my cholesterol went from 249 to 170."

Cisna says his daily meal routine started with two Egg White Delights, a bowl of oatmeal and 1 percent milk for breakfast. For lunch, he picked between a Southwest Salad or Bacon Ranch Salad with fruit parfait and apple slices. For dinner, he typically ate a value meal.

"I had french fries almost every day of this experiment," Cisna told WOLO-TV.

While nutrition experts say they aren't surprised by Cisna's results since he was picking healthy options, they don't recommend eating out day after day.

"You can get the healthiest option, you can get salads, you can get egg whites, that sort of thing, but the chicken they put in those salads, it will have a lot of sodium in there and that can definitely make your blood pressure go up," Sports Dietician and Certified Personal Trainer Kristen Ziesmer said.

Cisna says he's continued the McDonald's diet for another three months and added additional workouts. He's lost nearly 60 pounds total and is traveling the country talking about his experience and the important of food choices.