A man lost four stone in six months after adhering to a McDonald's-only diet.
John Cisna, from Iowa, US, initially started eating at the fast-food chain as part of a three-month classroom experiment, but continued with it and ultimately lost as much as 60lbs.
He's subsequently been made an ambassador for McDonald's, with a spokesperson saying: "Today, John serves as an official brand ambassador for McDonald's and travels the country sharing his story about the importance of choice and balance."
Meanwhile, John said his weight loss proves there are healthy meals to be found at the restaurants.
He said: "You can eat any food that you want to - but it's calories in and calories out.
"Enjoy the food like they were meant to be."