An Iowa teacher who ate nothing but McDonald's food for three months actually became healthier.

After watching the 2004 documentary "Supersize Me," Ankeny resident John Cisna decided to make his own amateur documentary about eating McDonald's for 90 days, KCCI 8 News reported.

He and his team of students at Colo-Nesco High School came up with the theory that McDonald's food could be consumed in a balanced way.

"I can eat any food at McDonald's (that) I want as long as I'm smart for the rest of the day with what I balance it out with," Cisna said.

The science teacher talked to the owner at the local McDonald's, who agreed to provide the three months' worth of meals to Cisna for free.

Cisna and his students detailed a plan: 90 days of only Golden Arches food for breakfast, lunch and dinner, while staying within a daily 2,000-calorie limit and keeping as closely as possible to health guidelines for carbohydrates, proteins, fats and cholesterol.

The teacher also began walking for 45 minutes a day. After three months, he had lost 37 pounds and found that his cholesterol had dropped from 249 to 170.

Cisna's usual breakfast during the McDonald's experiment was two egg white delights, a bowl of their maple oatmeal and 1 percent milk, according to KCCI 8. While lunch was typically a salad, dinner could be more indulgent.

"So this isn't something where you say 'well he went to McDonalds and he only had the salads. No, I had the Big Macs, the quarter pounders with cheese.  I had sundaes, I had ice cream cones," Cisna told KCCI 8.

The point of the experiment was to show the importance of watching what you eat, Cisna said.

"The point behind this documentary is, 'Hey, it's [a] choice. We all have choices. It's our choices that make us fat not McDonald's," he said.

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