I liken a diet break to that fuel and toilet stop you do on a long journey. As in, you might get to your destination sooner. But, the journey will be a lot more pleasant with planned implemented breaks.
A diet break is a planned 7-14 day break, you have every 2-3 months in your dieting phase. It’s an opportunity to eat more, bringing your calories back to maintenance. It helps offset dieting fatigue, metabolic adaptation, hormonal adaptations and gives you a nice, well-deserved break.
Why take a diet break?
I understand, we want to lose weight as quickly as possible. It sounds counterintuitive to slow the process down, but here me out…
Fat loss/dieting is physically and mentally stressful, so your body needs to have a form of release. (1) I know it sounds more impressive to say that you battled through, but if you want to win the long game, it’s important to know when to taper things back.
As I said earlier, if you’re driving and need the toilet, is it worth driving another 3 hours? Or would you prefer to release all that tension out of your system and enjoy the journey more?
How dieting can slow your metbolism
So to understand, why taking a diet break is important, it’s important to understand the adverse effect dieting can have on our metabolism.
Our metabolism is made of various components and when you diet, each one takes a hit. This means when you drop your calories, your body will burn fewer than usual.
These are the components that form your metabolism.
- Basal metabolic rate
- Thermic effect food
- Non-Exercise Activity Thermogenesis
- Exercise Activity Thermogenesis
Basal metabolic rate
This is the number of calories you’d burn if you were to lay in a coma. This accounts for around 60-70% (2) of your total daily calories. This is the one component of your metabolism you cannot change.
This is what influences your Basal metabolic rate:
When you diet, if you lose weight, you’ll weigh less. The less you weigh, the fewer calories you burn. So the more you diet, the less you will burn.
Thermic effect food
When you eat, your body needs the energy to break that food down. This accounts for 10% of your daily calorie burn (3). Therefore for every 100 calories you eat, your body burns about 10. Therefore when you diet and eat fewer calories, your body is burning fewer calories, as it is not breaking down as much food as usual.
Non-Exercise Activity Thermogenesis
This is all the activity you do in a day, which is not classed as exercising. Walking and fidgeting etc. When you eat fewer calories, when dieting, your body will try and downregulate, thus decreasing your level of NEAT. (4) This is a basic survival mechanism. This is why people that diet, tend to move around a lot less.
Exercise Activity Thermogenesis
Self explanatory and like NEAT, you’re more likely to move less, thus burn less.
If you want to know how many calories you burn in a day, use my calorie calculator.
How a diet break can improve your metabolism
Now we know why we need to take implemented breaks, lets look into what benefits they actually bring us.
- Mental release
- Improved mindset
- Less hunger
- More energy
- Less cortisol
When you’re told not to think about a pink elephant, what are you going to think about? It’s the same with dieting. The more you think about eating less, the more you think about eating. The longer and harder you’ve been dieting, the worse it’s going to get.
By having a couple of weeks, where you can eat what you want, those food urges will soon dissipate and you’ll actually be excited to diet again.
You’re not supposed to be on a diet for the rest of your life, I know shock horror. Lots of us are always on some kind of diet. People are brilliant at losing weight, most people have lost weight in their life. What people suck at and I mean really suck, like monumentally suck at; is keeping off the weight they lost. (6)
Most people gain all the weight back within 5 years. (7)
A few reasons people suck at keeping weight off is, they have no exit strategy and they don’t understand how weight loss works, so aren’t educated on keeping it off. (8) Finally, most people have never practised eating at maintenance. It’s either diet or binge.
Having a diet break, where you eat at maintenance, is going to give you practice and a good idea of how you’ll be living long term. When you do lose weight, you’ll already know what you need to do to sustain it.
Your body is a complex organism and it does all this crazy stuff to protect you. We know dieting causes you to burn fewer calories than usual. However, dieting also causes you to eat more calories than usual.
You have these two hormones:
They help keep your body weight at homeostasis (homeostasis is keeping things the same). (9) When you are dieting, these hormones go out of balance, so your hunger increases. From an evolutionary perspective, this makes total sense. At a point in time food was scarce and needed for survival.
Leptin is the hormone that tells your body it’s full and doesn’t want more food. When you’re low on food or been dieting for a long time, the amount of Leptin in your system decreases. (10)
The opposite to Leptin.
This hormone increases when you are low on food and decreases when you have enough food. (11)
Ghrelin is telling your body that you’re hungry and need food. This is why you have those uncomfortable hunger feelings when you’re on a diet.
S,o by having a period where you bring your calories back to a normal level, you are allowing these hormones to come back to balance. When they are back to balance, you’ll be in a far more comfortable place, to start dieting again.
Increase in energy
When calories have been restricted for a prolonged period of time, your body has crafty ways of trying to make you eat more. Your body is also going to try to stop you from moving as much, to decrease the number of calories you burn in a day. (9) Again, this is to stop you from starving to death.
For instance, the sloth does such little movement, they only need 110 calories per day to survive. (10)
When you’re taking in less energy, your body will find ways to decrease your energy output, decreasing your energy expenditure, without you even realising. (11)
You’ll probably do more sitting compared to normal. Your daily step count may decrease. The biggest takeaway is; your levels of ‘Non-Exercise Activity Thermogenesis’ (NEAT) will decrease, all the unconscious movements that don’t exercise.
This means if you usually burn 3000 calories a day and you’re on a low-calorie diet. You may end up burning 2000 calories a day. Your body is trying to get you to move less, to burn fewer calories, to prevent the chances of you dying. This is known as metabolic adaptation, which usually gets confused with starvation mode, which is a total myth. (12)
By eating more food, this signals to your body, that it doesn’t need to down regulate NEAT anymore. This means you’ll be moving more often again.
Cortisol is a stress hormone. When dieting, your rate of cortisol will increase, as dieting is stressful for the body. (13)
Unfortunately, if cortisol is in the system long enough, it raises blood sugar. When blood sugar is constantly high, insulin needs to be secreted and high levels of insulin, usually mean higher levels of hunger. (14,15)
So by bringing your calorie intake back up to normal, your energy levels will come back to normal. Your calorie output will increase and you’ll be burning more calories again. This will make going back into your diet a lot easier and prevent constant plateaus.
How do I go about taking diet break?
There are two ways I suggest you go about doing a diet break.
- Track calories to maintenance levels
- Eat to fullness
Track to maintenance
This is my opinion is the simplest way. Find out what your new maintenance calories are and eat to that amount. Your new calorie amount will be lower now, as you’ve lost weight, you’ll weigh less, therefore burn fewer calories. To play it safe, I recommend you use my calculator and start on the lower end of the maintenance recommendation.
Why this works so well is because it gives you a good reflection of what life will look like, once your diet is over. What I have noticed is people are shocked at the amount of food, they can actually eat once they have lost weight.
The only drawback of this method is, you’re still counting calories. This can be mentally fatiguing and the idea of a break is to break the fatigue. This is something you might want to think about.
Eating to fullness
This requires you to be more intuitive. Here you’re not counting calories, you’re going with your bodies hunger cues. This isn’t an invitation to eat everything in sight though. You’re going to eat similar to what you were eating on your diet, similar structure etc. The only difference is , you’ll eat a bit more, preferable in the form of carbohydrate.
As you’re not counting calories, youre going to let your body count for you. To make this easier a few steps can be implemented.
- Sit and eat at the table
- Turn off your phone, TV, or laptop
- Put down your cutlery between each bite
- Set a stopwatch off for 10 minutes and try not finish before
Most of us eat on the go and subconscious, when we make a more conscious effort, it is far harder to overeat. (16)
When do I need to take a diet break?
In general, it’s advised after every 3 months to implement a diet break. If you’re leaner, 2 months might be more beneficial.
You want to have these breaks planned into your diet, this allows for structure and focus and less off the cuff bingeing.
There is no real blanket timing as to when. It’s an as per need basis. As a vague rule of thumb, the more weight you have to lose, the fewer times you’ll need to have one.
If you’re carrying a lot of weight, you’re more likely to be highly motivated, so will probably not need as many breaks. Also your body will be feeling a lot better with the weight loss. However, if you’re just carrying an extra 10 pounds or so, you might benefit from a few breaks, as it is harder to lose fat when you’re leaner. This is because all the adapatations I mentioned earlier, will be fighting hard against you.
How long does my diet break need to last?
Two weeks, looks to be the point, when most of the dieting adaptations are reset.
One study showed 2 weeks, gave participants really good results. Also from my own experience, 7-14 days does seem to be the sweet spot. (17)
1-2 days break might be helpful, if you don’t want to diet on the weekend or if you have birthdays, weddings, etc coming. But on the basis of restoring energy levels and hormones, I don’t think if that’s enough time (I am yet to find any literature or studies to suggest otherwise).
Overall aim for 1-2 weeks and see how you feel from there.
Weight gain in a diet break
You will gain weight in your diet break. I have gained up to 6 pounds in one night during a diet break. This is not to be feared I promise. Changes in body weight, don’t always correlate with changes in fat levels. Bodyweight and body fat are not the same thing. This weight gain is not fat and even if it is fat, it’s only a minuscule percentage and will be lost as soon as your diet again.
So where does this extra weight come from?
- Restored glycogen
- Extra food in your system
- More water in your body
Glycogen is a carbohydrate that gets stored in the muscle and liver, to use when the body is low on blood sugar. However, when we diet, our glycogen stores deplete, as we tend to eat less carbohydrate compared to normal.
The average body stores 600g of glycogen. For every gram of glycogen some holds, that comes with another 3-4g of water. Therefore if you’ve depleted all your glycogen stores in your diet and after your break, they’re fully replenished. That’s 3kg or 5-6 pounds of weight you’ll have gained. Not a single gram of that was fat. (17)
This is often overlooked. But when you’re dieting, you’re eating less food, therefore by default, you’re not going to have much food inside you. When you’re not dieting and eating an extra 500-1000 calories each day, guess what? You’re going to have more food inside you. By just food alone, that is going to equate to an extra 1-2 extra pounds on the scale, which is not fat.
If you’ve been dieting, you’re more likely to eat foods lower in sugar and salt. Foods higher in sugar and salt, tend to be higher in calories and taste nicer, making you want to eat more. When on a diet break you can eat more of these foods, as you have the extra calories. But when you eat saltier foods, such as a takeaway, you’re going to retain more water.
This is your bodies ways of trying to sustain equilibrium. Where there is a lot of salt and sugar, there is going to be a lot of water. So by the basis alone, you should expect another couple pounds of water in your system alone.
Despite knowing this, most people still find the extra weight gain psychologically challenging.
Here are a few pointers I believe will be really helpful:
- Give the scales a break for the whole diet break. Give yourself another week or two after you start dieting again to start weighing yourself.
- Instead of focusing on your weight, now is the perfect time to use the extra energy you have. Focus on your performance.
- Put more emphasis on how you feel in all other aspects of your life. Once you have finished dieting, this is going to be your normal.
- Remember you are eating to maintenance. This is not a free for all. Still, be mindful
Diet break evidence
A 2018 study, known as the MATADOR study had a bunch of “obese men” either diet straight for 16 weeks or diet for 2 weeks on and 2 weeks off. The guys who dieted on and off, achieved greater fat loss and the study mentioned, that their rest periods may have reduced the compensatory dieting effects, which I spoke about earlier. (18)
A 2021 study had 26 people, men and women, diet for 12 weeks, with 1-week diet breaks in between. In the study, when their calories were bought up to maintenance, via carbohydrate, they did gain weight, but none of it was fat. After their breaks, when they were dieting, they felt less hungry compared to usual, more full, less irritable and a greater sense of satisfaction. (19)
Do I think you must have diet breaks, to lose fat? No. But do I think they are a useful tool to implement? Absolutely 100% yes.
It depends on the amount of weight you need to lose, on how often you’ll break. But instead of having those mad moments, where you can’t cope anymore, implements a few breaks here and there, be patient and try to enjoy the process.
Josh is a Registered Associate Nutritionist, with the Association for Nutrition (AFN). He completed his degree in Nutrition at the University of Roehampton in 2021. He passed with a First Class with Honours.
Josh is also a tutor for up-and-coming Personal Trainers, where he teaches a Level 4 Advanced Nutrition course. This is for Personal Trainers looking to upskill their nutrition knowledge. This is done at Norfolk Health & Fitness.