Metabolic confusion is the cornerstone of some of the most popular diets taking the internet by storm. This includes VShred, Noom, and, of course, the Metabolic Confusion Diet.
But unlike a lot of other fad diets, there seems to be good reason for believing that the principles of the metabolic confusion diet could be applied for sustained weight loss and may help dieters lose weight without piling on the pounds again later.
On the most basic level, metabolic confusion works by calorie cycling. You spend periods of time on a restricted diet followed by periods of time on a maintenance calorie diet. The purpose of this is to stop your body from adapting to existing on restricted calories and consequently reducing your basal metabolic rate.
In theory, calorie cycling lets you maintain weight loss through calorie deficit indefinitely, rather than seeing you need to continually increase your calorie deficit to see results. It should also make you less likely to put weight back on once you decide to stop dieting.
But let’s take a closer look at the metabolic confusion diet and why it may be a game-changer when it comes to long-term and sustainable weight loss.
Principles of Weight Loss
While there are many different ways to transform your body, if your goal is to lose weight in the form of stored fat, you need to create a calorie deficit. You need to burn more calories than you consume so that your body is forced to use stored fat for energy.
So, at the core of all weight loss plans tend to be three common principles:
- Eat fewer calories
- Get more active to burn more calories
- Build muscle so that you burn more calories in a resting state (increase you basal metabolci rate)
Most people, when they start a new weight loss regimen based on these principles, tend to start losing weight as they successfully create the required calorie deficit.
But most people also find that after a while, their progress stalls and they either get stuck, or they start to gain weight again.
Adapting to Survive
Weight loss starts to plateau on a simple calorie deficit diet because our bodies are adaptable and have an innate survival instinct. When calories are scarce, our metabolism slows down so that we can survive on fewer calories. This means that if we continue doing the same things, maintaining the same calorie deficit, we won’t see the same results because our body now needs fewer calories.
The temptation can then be to increase the calorie deficit by eating less and exercising more. But we tend to quickly reach a point where increasing the deficit becomes unsustainable.
Moreover, when we do eat food rich in carbohydrates, our body’s preferred source of energy, our adapted scarcity bodies can get excited. They identify a big energy input and often choose to save that energy for a rainy day since energy is in short supply. The result? Those carbohydrates may get stored directly as fat.
Plus, feeling their scarcity, our bodies will do other things to encourage us to eat the energy it needs. This means that we can be subject to food cravings that can force us to fall off the wagon and indulge in carbohydrate-rich foods, which then get stored as fat.
This adaption mechanism is why many people not only plateau while pursuing their weight loss goals, but often find themselves piling on kilos after an extended period of dieting, despite the fact that they have not increased their calorie intake.
The underlying principle of the metabolic confusion diet is to maintain a calorie deficit without allowing your body to reduce your metabolism and enter starvation mode.
It does this by rotating between low calorie days and normal consumption days. In this way, you restrict your calories to aid in weight loss, but then you return to normal calorie consumption before your body starts to get worried about scarcity and starts conserving energy and storing fat.
There are no strict rules about exactly how you cycle your calorie days. You might spend as little as three days on restricted calories, for example, less than 1,200, before returning to a stable level of calories, probably somewhere between 2,200 and 2,500 calories. But you might also go longer, passing eleven days on calorie restriction, before having three days of normal calorie consumption.
This type of diet is not too different from intermittent fasting, except that you could not fast for longer periods such as eleven days. Plus, it is easier to stick to as when intermittent fasting you need to restrict your calories to less than 500 a day, which is very challenging.
Many people believe that this diet is easier to stick to than others, as you can still enjoy your favorite foods – chocolate cake, hamburgers, and more – just not every day. It can also be easier to work your restriction days around big events, so you don’t have to miss out when a little bit of indulgence also has a social reward element.
Weight loss might be slower, as your weekly calorie deficit is lower than if you were restricting calories every day. But the belief is that the period of weight loss is more sustainable, since your body’s natural defenses do not jump into to stop you.
As well as cycling between calorie intake levels, it is recommended to cycle carbohydrate intake.
Carbs are your body’s preferred fuel source, and if carbs are available in the system, your body will burn them for energy. But if carbs aren’t available, then your body will turn to its next best energy source, stored fat.
So, if you are trying to lose weight, it is a good idea to reduce carbohydrate intake. But just like with calorie restriction, if you reduce your carbs too much, your body will adapt. But these adaptions aren’t necessary positive. One of the first things that happens is often a change in the hormone production in your thyroid specifically designed to slow down your metabolism.
This is why it is beneficial to cycle carbohydrates as well as calories, restricting carbohydrates on your low-calorie days, instead focussing on protein and healthy fats, and then eat a normal amount of carbs during normal calorie consumption days.
Great, so if metabolic confusion works, what is the ideal calorie cycling interval to maximize results while preventing your body from adapting to a new diet?
Well. First and foremost, there is no undisputed scientific evidence that the metabolic confusion diet works. That is because the experiments have not been conducted. Hopefully, more concrete information about this will emerge in the near future. Until then, we only have the anecdotal evidence from people who have used the diet that it works.
As for the ideal internal period, we may have more information on that. As far back as the 1940s experiments were being conducted to see how the body reacts to calorie restrictions.
Between 1944 and 1945 a 24-week experiment was conducted with a group of men to see what would happen when their daily calorie intake was halved. They were also required to walk 35 kilometers per week and complete other physical tasks. This was the first experiment to show that basal metabolic rate – the number of calories that a person needs just to sustain themselves – dropps at a rate disproportional to the amount of weight that lost (since lighter people need fewer calories to sustain themselves).
Since then, numerous studies have tried to better understand how these adaptations work. The verdict?
On average, your body will only start to adapt to a calorie deficit after about two weeks, which suggests that a two-week calorie deficit window is probably ideal for weight loss.
However, it is worth noting that there are always outliers who adapt more or less quickly, and therefore that self-monitoring is required to find the “sweet spot” for you. It is also worth noting that most studies are conducted on men only, so women may have slightly different cycles.
A 2018 study found that repeated rounds of two weeks of dieting followed by two weeks of maintenance for 30 weeks achieved the same level of weight loss as sixteen weeks of continuous dieting. But while the process took longer, the basal metabolic rates of the cyclic dieters remained higher, which means that they were much more likely to maintain their weight loss, rather than pile on pounds when they started to eat normally again.
But do you need to stick to maintenance calories for two weeks if you reduce them for two weeks? No. Studies suggest that you should stick to maintenance calories for 25-50% of the time you spend on reduced calories. So, if you reduced for two weeks, you should maintain for 4- 8 days.
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Does metabolic confusion work for weight loss?
There are still not enough studies on metabolic confusion to say with certainty that it is one of the most effective strategies for weight loss. However, anecdotal evidence and a limited number of studies suggest that it is an ideal approach for long-term weight loss. While it generally means taking a slower approach to losing weight, dieters are less likely to encounter unexpected plateaus or start piling pounds again after extended periods of dieting.
How do you do the metabolic confusion diet?
The metabolic confusion diet is relatively easy to follow as it is a simple matter of cycling between low calories intake days, with calories eat around the 1,200-1,500 mark, and maintenance calorie days, set around the 2,000-2,500 mark. Beyond this, there are no specific rules about what you should or should not eat. However, if you prefer to follow a low-carb diet, it is recommended that you eat a normal amount of carbohydrates on maintenance calorie days.
How you cycle your calories is up to you. Some people restrict for three days and then maintain for one, while others might restrict for 11 days and then maintain for three. Studies suggest that the optimal restriction period is two weeks, with a 4-7 day maintenance period.
How do I boost my metabolism?
There are many effective strategies for boosting your metabolism. Among the most effective are eating plenty of protein, drinking lots of water, building muscle, and getting a good night’s sleep. There are also supplements available to boost your metabolism for limited amounts of time.
So, what’s the verdict?
Diets that utilize calorie cycling represent an unproven but promising approach for sustained weight loss both because they help maintain your basal metabolic rate, and because this diet tends to be easier to stick to then more extreme diets.
The principle behind the diet is that when we continuously restrict calories for extended periods of time, our body adapts to the new lower calorie intake. Not only does this mean that we need to further restrict calories to maintain weight loss, but that our energy-poor bodies will often try and encourage us to consume more calories, and then store them as fat for a rainy day because it is worried about scarcity.
On a calorie cycling diet, also known as a metabolic confusion diet, you eat a calorie deficit, but then return to a normal calorie intake before your body has a chance to adapt to lower energy levels. You can then return to a calorie deficit for another period of weight loss.
In theory, this will make your periods of calorie deficit more effective, as your basal metabolic rate remains high, and you shouldn’t quickly regain weight after dieting as your body is not starved for calories.
The maximum period for calorie restriction should be about two weeks. You should then maintain regular calorie intake for 25-50% of the time of your deficit, so 4-7 days, before you can return to your calorie deficit for another two weeks.
One of the good things about this diet is that the focus is not on what you eat, so it is compatible with most approaches to nutrition, whether that be Vegan or high protein. However, it is best not to completely cart out carbohydrates, as this can mess with hormone production by the thyroid. If you choose to eat low-carb, increase your carb intake during your maintenance calorie period.