This post is taken from the Vitamin. Every Thursday, I drop some knowledge bombs on your face to help you reach your goals faster while avoiding all the bullshit.
You know when you’ve been in a deficit for a while, and things start to feel a bit sucky? Hunger is high, you have the energy levels of a sloth on Xanax, you’re irritable, and you start to question whether this dieting stuff is even worth it.
Well, friend, you’re in luck! I’m about to tell you about a top-secret diet strategy that’ll have you back to your perky self in no time while making progress on your goals.
What I’m referring to––if the title didn’t give it away––is a diet break.
As you diet and get leaner, a cascade of hormonal changes occur to prevent you from losing more body mass and ostensibly starving to death, including but not limited to an increase in hunger, lethargy, fatigue, and reduced energy expenditure which can stall fat loss.
To combat these negative side effects, a common recommendation is to implement a 1-2 week “diet break” where calories are increased to maintenance. By doing this, the theory goes, some of the metabolic adaptations are reversed, and you can get back to dieting with renewed zeal.
Here’s the kicker, though: Despite how commonly diet breaks are recommended, you might be surprised to learn research on the topic is still sparse and, up until recently, has only been done in sedentary, overweight individuals. 1 2
That all changed in 2021 when a group of researchers published the first diet break study on resistance-trained men and women. 3
The researchers found a diet break wasn’t more effective than continuous dieting for increasing fat loss, preserving muscle mass or maintaining resting energy expenditure. However, the diet break did seem to lower the drive to eat due to increased fullness.
Well, we now have a brand new diet break study that revisited the topic in a group of young, resistance-trained females. 4
What did the researchers do?
38 resistance-trained females were randomised into two groups:
1. Continuous diet group: This group was prescribed a 25% deficit from their predetermined maintenance intake and dieted continuously for six weeks.
2. Diet break group
This group was also prescribed a 25% deficit from their predetermined maintenance intake and dieted for six weeks, but also included two diet breaks where they ate at maintenance.
Both groups followed the same macro targets:
- 1.8g/kg (0.8g/lb) of protein
- 40% of calories came from fats
- 60% of calories came from carbs
Participants resistance trained 3x/week with a volume-matched alternating upper/lower split, and all working sets were taken to 2 reps in reserve (i.e., they stopped 2 reps from failure).
Alongside the resistance training, participants were also instructed to engage in 30 min of low- to moderate-intensity cardio twice per week. Participants in the diet break group were told to refrain from cardio during the diet break weeks.
The main finding of this study was that a diet break didn’t provide any benefits to body composition or resting energy expenditure when compared with continuous dieting.
Across all participants:
- There was a mean decrease in body weight from baseline to post-intervention (62.7 kg to 61.5 kg).
- fat mass decreased from 15.9 kg to 14.7 kg.
- There was no change in muscle mass.
- Resting metabolic rate didn’t change over time (1422 kcals to 1434 kcals).
There weren’t any differences in measures of satiety, ease of sticking to the diet, or motivation to diet for the week ahead.
However, the diet break group did experience a decrease in disinhibition (the desire to overeat) over the course of the study. In contrast, the continuous dieting group saw an increase in this parameter.
One likely explanation for this could be that a diet break allows people to eat a bit more food – and often fit in higher calorie foods they wouldn’t be able to during a diet – which reduced the desire to overeat during the dieting period. As the researchers write:
It is possible that by nature of the ability to “practice” restrained, but not excessively restrictive, eating throughout the two week-long diet break periods, participants in the INT group saw fewer deleterious effects of dieting on disinhibition than those dieting continuously, which may bode well for the maintenance of energy balance and weight loss results over the long term.
So are diet breaks pointless?
Two studies have now looked at the impact of a diet break using a resistance-trained population.
Both studies have arrived at similar conclusions: A diet break likely won’t do much to increase fat loss or preserve muscle mass or metabolic rate.
However, before completely writing off diet breaks, a few things to bear in mind:
- While a diet break didn’t do much for body composition or metabolic rate, this study found that it could reduce the risk of overeating. And the previous study on diet breaks found the diet break group experienced a significant increase in fullness compared to the continuous dieting group. 3
- Another study (which was a secondary analysis of the 2021 paper) found a one-week diet break increased mental alertness and reduced hunger and irritability while increasing fullness and food satisfaction. 5
These aren’t trivial things.
If a diet break can help improve mood, energy, focus, and dietary adherence, you’re more likely to stick to the diet over the long term versus grinding your way through a deficit despite feeling like shit.
A diet break is just a tool you can use if/when needed.
You certainly don’t need to force a diet break every few weeks like in the study reviewed—instead, diet for as long as it’s sustainable. When, or if, you reach a point where adherence becomes harder due to increased hunger and low energy, then you can take a week or two at maintenance (or longer if needed) before resuming the deficit.
Another way to implement a diet break is to coincide the break with holidays, events, or occasions where it’ll be harder for you to control food intake (or occasions where you may not want to track), allowing you to relax and not worry too much about your diet while taking advantage of the diet break’s benefits.
Thanks for reading. If you enjoyed this, you’d love the Vitamin
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