Diet Breaks
Diet breaks are a popular non-psychologist recommendation based on the intuitive appeal to ‘some downtime’ or ‘relief from the dieting’. As you should be able to predict by now, psychological science has something different to say about diet breaks.
Wing & Jefferey (2003) conducted a rigorous study on the effect of diet breaks on compliance with weight loss dieting.Their methodical approach involved dividing participants into three distinct groups, ensuring a comprehensive analysis of the topic.
Contrary to popular belief, the researchers hypothesized that diet breaks would disrupt diet compliance. However, the results were surprising. Most participants did not struggle to resume their diet after the break, regardless of its duration. This unexpected outcome led the flexible diet crowd to hail this study as the debunking of diet breaks.
However, if you logically think about the study results, using them to support flexible dieting or diet breaks doesn’t make sense. Diet compliance was similar in all diet weeks in all three groups. So, the diet breaks did not cause people to fall off the wagon, but they didn’t help either. Thus, the diet breaks were a waste of time.
Moreover, a closer inspection of the results reveals the detrimental effects of the diet breaks. “… lasting differences occurred after the third break of the short-break group when participants reported less frequent self-monitoring, less frequent self-weighting and a trend toward greater consumption of restricted foods. The long break group also tended to consume more restricted foods for the week after the break.”
The more incredible difficulty with food restrictions after diet breaks is precisely what you’d expect from the psychology of cheat meals and food choices. After a diet break, your mind’s internal menu is filled with foods not conducive to your fat-loss goals. As a result, you have more difficulty not eating these foods.
The more incredible difficulty with self-monitoring after a diet break is also not surprising. Weighing yourself and other forms of progress tracking is a matter of routine and habit. Breaks, by definition, break your habits.
The researchers dismissed these concerns because, in the long run, weight loss was similar between the three groups. However, the no-break group achieved a level of weight loss in 7 weeks, whereas the groups with the diet breaks took about 16 weeks to accomplish. If these were strength trainees, the no-break group could have spent those 9 weeks building muscle and getting more jacked.
Another study similarly found that interspersing 15 weeks of energy restriction with two 5-week diet breaks did not affect body composition change, resting metabolic rate or any health biomarker, compared to doing the cut in one go. At a follow-up a year later, there were no significant differences between groups, indicating that diet breaks did not make the fat loss more sustainable.
Again, fancy-sounding “The ICECAP Trial” done by Poes et al. (2021) studied diet breaks, this time in strength trainees who experienced tracking their macros. The trainees performed the same fat loss diet program in one 12-week stretch or four 3-week stretches with a 1-week diet break in between with maintenance energy intake.
At the end of the study, there were no significant differences between groups for an overwhelming battery of tests, including body composition, muscle strength, energy expenditure, levels of testosterone, thyroid hormone and leptin, behavioural measures (including physical activity, energy intake, diet adherence and attrition) and psychological responses to diet s (incl. Sleep quality, irritability, mood states and eating disorder behaviour). In other words, the diet breaks didn’t achieve any hard benefits, despite this group performing 3 more weeks of strength training at maintenance energy intake.
Interestingly, these results stayed the same when comparing the groups across the entire 15-week study period, meaning the constant diet group was doing a 3-week maintenance phase at the end that achieved nothing.
These findings strongly suggest that both diet breaks and maintenance phases are not the most effective strategies,from a purely physical perspective. This practical insight can guide individuals in making informed decisions about their dieting strategy.
However, the diet breaks did achieve 1 benefit: they resulted in lower levels of hunger and desire to eat with greater food satisfaction, as well as higher levels of the satiety hormone peptide YY. This benefit was not consistent, however, because there were no differences in ratings of fullness or prospective consumption or in levels of the hunger hormone ghrelin. It also didn’t lead to a difference in behavioral consequences of hunger, actual energy intake or overall diet adherence, so it’s questionable how practically relevant the difference in appetite sensations was.
Take home message on diet breaks
The diet breaks are primarily a waste of time. Any time spent on them could be more productively spent either cutting (fat-loss) more slowly or starting a lean bulk phase (muscle gain) earlier. When not correctly implemented, diet breaks may also cause you to fall out of your routines and break your habits. When it comes to diet adherence, consistently is a great value. In fact, the word diet comes from Latin via Greek (diaita) and originally meant ‘way of life’, not ‘ unsustainable period of self-deprivation resulting in short-term fat loss’. If you feel like you need a diet break, you should probably take a long, hard look at your lifestyle. If your lifestyle is not something you can sustain for weeks or months, how are you going to maintain it for the rest of your life? You need to address the problems, not run away from them and come back to see if they’re still there.