The science is still not definitive, but some experts say cheat days may help with weight loss by increasing the production of the hormone leptin, which decreases one’s appetite.
A day of eating what you want each week may also help the body burn more calories by increasing metabolism, according to some experts, and may have a psychological benefit.
“You can feel motivated to stick to your diet plan because you know that you're going to have a day where you get to eat a little bit of whatever you want,” nutritionist Maya Feller told ABC News.
But taking a cheat day to an extreme and eating thousands of calories would be a “disaster” for your waistline, Feller says.
Feller said she advises her clients to take a more moderate approach.
“When I counsel my patients, I actually don't talk about using cheat days,” she said. “I talk more about moderation, have one meal that is a little bit more decadent.”
ABC News Chief Women’s Health Correspondent Dr. Jennifer Ashton, who is also board-certified in obesity medicine and has a master's degree in nutrition, said today on "GMA" that the term "cheat meal" or "cheat day" does not come from medical, nutritional or behavioral science literature.
"That is something we make up in TV-land, in society, in our every day-to-day life," Ashton said, adding that it's important to remember how subjective the term cheating is when it comes to food.
"For one person it may be one cookie ever," she said. "For another person, it might mean the entire bag of cookies."
J.D. Roth, the author of "The Big Fat Truth" and the executive producer of ABC's "Extreme Weight Loss," said he does not recommend cheat days, comparing it to allowing a recovering alcoholic have a drink.
"The people I deal with are food addicts," Roth said today on "GMA." "They need to change their relationship with food and to have a ‘Sunday Funday,’ which is a day full of comfort food, usually comes with a side of remorse after it’s over. It’s a slippery slope."
Roth said that people trying to lose weight should feel in control of their food.
"Working small indulgences in, that definitely helps,” Roth said of his approach.
Ashton similarly recommends a balanced approach to weight loss.
"In my book, the best diets are ones that are safe, simple and sustainable so you can stick with it," she said.