The science behind Cheat Days: How you can actually LOSE weight with a scheduled junk food binge

The ‘cheat day’ is a controversial concept in diet circles.

Some view it as a small break from following a strict diet, such as eating a piece of chocolate cake or a slice of pizza over the weekend. 

But with the rise of social media, the concept has become more extreme, sometimes involving eating thousands of calories in just a few hours.

Yet science shows that there are benefits to scheduling a junk food binge into a healthy diet, with studies showing it can actually help you burn more fat, replenish vital hormones that make us hungry, jumpstart metabolism, and give people more energy to work out harder.

Actress Jennifer Aniston, 54, made headlines last week after a source said that she enjoys martinis or tequila on the days she strays from her strict high-protein, low-carb and low-sugar diet. 

And she’s far from alone. Dwayne ‘The Rock’ Johnson, 51, has also revealed that he indulges in a cheat day every week after six days of carefully crafted eating. His favorite treats that he’s shown off on social media include mountains of pancakes and multiple pizzas in one sitting.

Though not a new practice, it’s taken social media by storm. On Instagram, there are more than 4.2 million posts under #cheatmeal. On TikTok, #cheatmeal has 1.3 billion views.

‘It’s this idea of being super strict the majority of days of the week and then come around the weekend…really just the freedom to eat whatever you want, however much you want [within a certain time window],’ Lindsey Joe, dietitian in Nashville, Tennessee, told DailyMail.com.

Restricting calories can decrease the amount of leptin in the body. Leptin is a hormone released by body fat that helps maintain body weight over long periods of time. 

Leptin regulates hunger and signals to the body that it’s full.

As you cut calories and body fat begins to dwindle, some research suggests that leptin decreases as well. Those studies suggest that cheat days can help restore leptin. 

A review published in the journal Sports suggested that alternating days of calorie restriction with days increased calorie intake helped athletes reach their weight goals faster. 

The researchers said that cheat days restore energy levels and stimulate the production of hormones like leptin that can result in fat loss, increase satiety, and boost metabolism.

In a 2018 study, researchers divided obese men into two groups: one that stuck to a strict meal plan and another who took short breaks from the diet. The participants who took intermittent breaks lost more weight and gained back fewer pounds after the trial. 

A set of three experiments published in the Journal of Consumer Psychology evaluated if participants would be able to stick to their goals better if they were allowed cheat days. 

In the first experiment, participants imagined either being on a 1,500-calorie diet every day or a 1,300-calorie diet with a 2,700-calorie splurge day at the end of the week. Those with the splurge option predicted that they would have more self-control by the end of the study and that they could come up with better strategies to overcome temptation than the 1,500-calorie group.

In the second experiment, 36 participants actually followed one of the two diets for two weeks. Those who had a cheat day reported that they had more motivation and self-control than those who didn’t have that option. 

Both groups lost similar amounts of weight on average.

In the final experiment, when participants were asked to describe their personal goals, those on the cheat-day plan said the splurge was more helpful for their motivation, regardless of what their goal actually was. 

However, other research shows that cheat days could have negative impacts as well.

Early research has suggested that overeating, which could constitute cheating for some, only boosts metabolism between three and 10 percent, and this lasts for no more than 24 hours. 

However, other older studies have shown that temporarily increasing calorie intake could increase leptin production by nearly 30 percent for up to 24 hours.  

Research published in April in the journal Molecular Nutrition & Food Research found that mice who ate healthy diets but hinged on high-fat, high-sugar diets showed cognitive impairments. The mice scored significantly worse on spatial memory tests in which they had to remember where objects were placed. 

The researchers also linked the unhealthy eating to increased inflammation, which lowers cognitive function. 

A study published last year in the Journal of Eating Disorders found that over the course of a year, over half of adolescents and young adults sampled had at least one cheat meal. Cheats meals in these participants were associated with several eating disorder behaviors, including binge-eating, compulsive exercise, and fasting. 

‘Research hasn’t fully explored eating behaviors purported to increase muscularity and leanness, such as cheat meals,’ lead study author Kyle T Ganson said in a press release. 

Though cheat days could increase motivation, there could also be mental health drawbacks, Ms Joe said. ‘Maybe you’re not where you want to be because of the cheat day that transpired, and you may end up feeling really defeated and down and out about your progress.’

The term ‘cheat day’ can also have a negative connotation because it insinuates breaking the rules and labels certain foods as ‘bad.’ ‘Who are we cheating?’ she said. ‘I think it can also perpetuate these unhealthy dynamics…I feel like it drums up a lot of extra emotional baggage that doesn’t necessarily have to come with your food choices.’ 

‘This is particularly important given the popularity of cheat meals that is well documented on social media. We needed to explore whether there are associations between cheat meals and eating disorder psychopathology.’ 

Ms Joe recommends instead of focusing on ‘good’ foods versus ‘bad’ foods, listen to cues from your body that signal you’re hungry or full, such as lightheadedness, moodiness, to control portion sizes and not overdo it. ‘Strengthen that relationship with food and keep the emotional baggage out of the equation here.’

If you do want to treat yourself for doing well on your diet, she suggests non-food rewards, like buying yourself a new gadget for your kitchen or storage containers for meal prep, that support a healthy lifestyle. 

‘You don’t have to be perfect,’ Ms Joe said. ‘It doesn’t have to be all on or all off in order to get to where you want to be.’