Cheat days are every dieter’s favorite day of the week — they’re the days when (for once) you can eat whatever you want whenever you want it on your diet. But only for a day, which means cheat days can get wild. In fits of deprived excitement, dieters will gorge themselves on pizza, booze, burgers, and grotesque amounts of dessert in an attempt to get the enjoyment they want while they can. It’s the binge-restrict cycle at its finest.
The logic behind cheat days is simple. Without at last one day of freedom, your diet will drive you crazy — though we’re not sure that inhaling entire pizzas is the best representation of sanity.
Now, a study from the Journal of Obesity is stating that dieters who take cheat days lose more weight in the short term than dieters who restrict consistently. On the surface, this seems counterintuitive. The dieters who take a cheat day are ingesting way more calories! But the “calories in, calories out” model doesn’t work, and this study is a prime example.
The study, conducted in Australia, examined a group of obese men for four weeks. The diet entailed reducing their caloric intake by a third. One group of dieters adhered steadfastly to the restriction for the full four weeks. The other group maintained the habit for two, and then was allowed to fall off the rails of the caloric limit.
During the two weeks where they’d ditched the caloric deficit, they were instructed to equate their calories burned with calories eaten.
Once the study had finished, both groups gained back some of weight they’d lost (and in some cases, gained back more). The group that took the break from the calorie deficit gained back less weight than the group that did not by approximately 17 pounds.
“While further investigations are needed around this intermittent dieting approach, findings from this study provide preliminary support for the model as a superior alternative to continuous dieting for weight loss,” said Nuala Byrne, leader of the study.
It’s difficult to draw conclusions about cheat days and diet efficacy from this study alone. The study did not examine the long-term impacts of the diets or account for the exercise habits, histories of dieting, and other lifestyle factors that could affect participants’ weights. Additionally, the study did not attempt to explain the consistent weight gain that occurred after the diet had finished.
If you interpret these results while also taking into account the negative effect restrictive dieting has on health outcomes in the long term, these results make sense. Bodies often “fight back” against caloric restriction by fluctuating metabolism and, eventually, gaining more weight back than was lost. So the less dieting that occurs, the less damage is done to the dieter’s metabolism. But both groups gained back weight — so perhaps the problem was the one thing the groups had in common, i.e., the diet in the first place.
Another questionable aspect of the study was the “release” from the diet in the “cheat week” group. The dieters took time off from the caloric restriction, but were still arguably on a diet. So what happens to the body when you fluctuate between restriction and flying off the rails? Science has yet to tell. Here are some things science did tell us in 2017.