An Iowa biology teacher said he lost 37 pounds and saw his cholesterol drop significantly after eating nothing but McDonald's for three months, Time.com reported.

As part of a school science experiment, John Cisna, 54, ate a 2,000-calorie-a-day McDonald's diet designed by his students. The students planned a diet that stayed within recommended allowances of nutrients like carbohydrates and fat calories.

"This isn't something where you say, 'well he went to McDonald's and he only had the salads.' No, I had the Big Macs," Cisna told FOX WGHP.

A typical breakfast for Cisna would be two egg white delights, a bowl of their maple oatmeal and a carton of 1 percent milk. For lunch, he would usually eat a salad. And for dinner, he would opt for a more traditional value meal, including items like Big Macs, ice creams and sundaes, Times.com reported.

During the experiment, Cisna also walked 45 minutes every day.

At the end of the experiment, Cisna discovered that he was actually healthier than when he started. Cisna said that in addition to losing 37 pounds he lowered his cholesterol from 249 to 170.

The school teacher, who now weighs 170 pounds, said the moral of the experiment isn't to eat more at McDonald's, Cisna said, but to pay attention to your daily nutrition and what you eat.

"We all have choices. It's not McDonald's that makes us fat," Cisna said. "It's our choices. 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."

The Examiner reported that the manager of the local McDonald's Cisna frequented on a daily basis decided to provide all his food for free after learning about the experiment.