McDonald's has ended a controversial practice of giving nutrition advice to students in schools, pulling back on a program that critics said was a subtle form of fast-food marketing that could imperil kids' health and understanding of nutrition.

The company has stopped sending John Cisna, a middle-aged teacher from Iowa who came to fame after claiming to have lost almost 60 pounds eating only McDonald's, into schools to talk with children. It also stopped supplying related materials, including a video documentary that was shown to kids about how Cisna lost his weight.

McDonald's had said the program, carried out by local franchises, was intended only to educate students about nutrition and good habits at a time when fast food is a key part of many diets. But critics, including some parents and health experts, complained that it sent a confusing message that left kids thinking that burgers and fries could be a regular part of a healthy diet. Cisna had traveled the country on the company's behalf for almost a year, telling middle and high school students about how he lost weight on a diet that regularly included Big Macs and french fries.

"John's currently focused on the opportunities that make the most sense for our brand at this time," Christina Tyler, a McDonald's spokesperson said. "Specifically, as our brand ambassador, John is currently focused on internal and local community events, and he is not appearing at schools."

McDonald's said in a statement this week that Cisna stopped those visits last fall, after a Washington Post article highlighted how McDonald's used its relationship with local schools and teachers' associations to get its message in front of students. Cisna didn't respond to requests to speak by phone, but he wrote in an emailed statement: "My focus has always been to encourage people to exercise and make more informed choices about food. Now I'm focused on and enjoying talking to employees and community groups about my story of choice and balance."

McDonald's announcement follows growing criticism of its efforts to push Cisna's story onto school children. McDonald's had long defended the practice, saying that Cisna's presentation was about choice, not about eating McDonald's. But critics argued it amounted to little more than a veiled attempt to woo customers at a young and impressionable age.

"There was a suggestion that if you look at what you're eating, you could eat at McDonald's for several days," Susan Strutz, a family and consumer science teacher at Baraboo High School in Baraboo, Wis., where Cisna spoke last September, told The Washington Post last fall. She said she thought it was inappropriate for him to speak to middle schoolers.

Bettina Elias Siegel, a food-law expert who sits on her Houston school's health advisory board and was approached by a franchisee about showing the documentary, has been one of the loudest voices criticizing Cisna's appearances at schools. She was the first to bring attention to the program, when she wrote about it on her blog in early October. She also launched a petition on Change.org pleading with McDonald's to stop the program, which has tallied almost 90,000 supporters.

"In the past, Cisna would tweet every few days about speaking at different schools around the country, but I noticed he stopped. His tweets suddenly were just about speaking to groups of adults," said Siegel, who suspected that McDonald's had stopped its program but had no way to verify.

"It's going to feel so good to be able to contact my almost 90,000 petition signers and say, 'Guess what? We faced off against one of the largest corporations in the world and we actually won!' " she said.

Cisna's experience has long been framed as a counterexample to the infamous documentary "Super Size Me," which was released in 2004 and chronicled what happened to a man who ate nothing but McDonald's for a month. For 180 days, Cisna says he ate nothing but McDonald's while limiting his daily intake to 2,000 calories per day. At the end, he says, he not only lost 56 pounds, but his cholesterol level fell, too.

His story, which he first chronicled on YouTube, landed him appearances on major television networks, and, eventually, led to him being hired by McDonald's as a "brand ambassador." In late 2014, the burger giant began using his video as the basis for a 20-minute documentary, titled "540 Meals: Choices Make the Difference." The documentary, which is available online, has now been viewed almost 100,000 times.

But the video didn't just live online - it was also being offered to students, educators and school administrators as a valuable nutrition lesson. Dietitians on McDonald's payroll, local franchisees and Cisna himself shared the documentary and additional materials, including letters urging schools to show the documentary, and an accompanying teaching guide, which specifically recommends that teachers show the documentary when "Super Size Me" is part of the curriculums, at various schools and school-related events.

"I don't decide where to go," Cisna told The Post in the fall. "They set up interviews on television and talks at schools."

Cisna made his last school appearance two weeks later, on Nov. 13. Neither the documentary nor any of the accompanying materials are being shared with or used at schools anymore, according to McDonald's.