Metabolism 101

Before we get into metabolic confusion, it’s important to understand what metabolism is and how it works.

Metabolism – The energy (calories) burned by processes in your body. Such as organ function, maintenance of muscle, breathing, and digesting food.

One of the key aspects of metabolism is that it responds to changes in your energy balance. This is known as metabolic adaptation or adaptive thermogenesis.

In other words, your metabolism adapts to calorie restriction, causing you to use less energy. “What sort of sorcery is this?”, you might ask.

Well, it’s actually a normal physiological response designed to keep you from starving. But it also makes weight loss very difficult.

After just 3 weeks of calorie restriction, your body already goes into “starvation mode”. Below is data from a 2015 study published in the American Journal of Clinical Nutrition.

In this experiment, more than half the weight lost was lean muscle. Because this slows down your metabolism, burns fewer calories, and restores the energy balance.

On average, the participants’ metabolic rate dropped by 9%. That may not sound like much, but it’s enough to slow or stop weight loss.

Real-World Example

Let’s say you normally eat 2,000 calories per day to maintain your weight. To lose weight, you follow the common advice of cutting 500 calories per day.

At first, your weight drops. But after several weeks the weight loss stops. Frustrated, you cut another 500 calories. Then the weight loss continues until you hit another plateau.

Figure 1. Visual representation of metabolism adapting to calorie restriction (exaggerated for demonstration purposes).

After 2 or 3 months of this game, you’re exhausted and hungry all the time – there’s no way you can cut more calories. So you give up and go back to eating 2,000 calories per day.

Unfortunately, your metabolism is shot. Which means you gain back all the weight – sometimes more than you lost.

If this sounds familiar, you’re ready to learn about metabolic confusion.

What Is Metabolic Confusion?

While there are many interpretations of metabolic confusion, the premise is the same. Basically, you mix up your calorie intake to prevent the metabolic crash that comes with calorie restriction.

But let’s get one thing clear, you’re not confusing your body. Nor should you have the mindset of trying “pull a fast one” or “cheat the system”. Instead, I prefer this definition:

Metabolic confusion is a nutrition plan that works with your body’s systems to optimize weight loss. Think of it as giving your body what it needs to maintain your metabolism.

One approach is called alternate-day fasting. A sort of feast/famine routine where you eat a very little one day, then a lot the next. But, studies haven’t shown this to be an effective strategy².

A better approach is called calorie shifting, or cycling. With this method, you follow moderate calorie restriction for anywhere from 3 to 11 days. Then eat a higher number of calories for a period of 1 to 3 days.

To illustrate, the graph below shows a cycle of 6 low-calorie days followed by 1 high-calorie day.

Figure 2. Basic metabolic confusion example.

This variation in calorie intake prevents a continuous calorie deficit. Which, in turn, stops your metabolism from adapting as quickly as it would with constant calorie restriction.

Yet, on average, you eat fewer calories than you burn. And that allows you to lose weight consistently.

Now that you understand the concept of metabolic confusion, let’s dive into how it works.

5 Ways Metabolic Confusion Helps You Lose Weight

1. Maintains Metabolic Rate

As I mentioned earlier, your metabolism adapts to the amount of energy you give your body. Therefore, occasionally eating more keeps your metabolic rate higher.

In a 2012 study, researchers compared calorie restriction to calorie shifting over a 6-week trial³. With the goal of comparing weight loss on these diets.

The calorie shifting group ate fewer calories than they burned for 11 days. Followed by 3 days where they could eat as much as they wanted. While the calorie restriction group ate fewer calories for the entire experiment.

In this case, calorie shifting resulted in about 1/3 of the change in metabolic rate.

Figure 3. Adapted from Davoodi et al.

By maintaining their metabolic rate, the calorie shifting group lost more body fat despite eating 300 more calories per day.

On average, the calorie shifting group ate 40% fewer calories than they burned. Also called a calorie deficit.

But they could have gotten better results by eating more! Let me explain.

2. Prevents Muscle Loss

Another reason metabolic confusion works is muscle preservation. The more muscle you have, the more calories you burn. So it makes sense to hang on to every ounce of muscle while you’re losing weight.

However, studies show that the rate of muscle loss increases exponentially as the calorie deficit increases⁴. That means an incremental decrease in calories results in a disproportionately large increase in muscle loss.

Figure 4. Each incremental drop in calories results in larger than expected muscle loss.

Fortunately, an average calorie deficit of less than 20% is the best way to prevent muscle loss. And I’ll show you how this is possible using metabolic confusion in the “how-to” section.

3. Boosts Energy

On a calorie-restricted diet, your energy levels drop. One reason is that low-calorie intake is usually accompanied by low carbs.

When you eat fewer carbs than you burn, your body’s energy stores get depleted. This stored form of carbohydrate is called glycogen.

With just one high-calorie/carb day, you can refill your glycogen stores and boost your energy levels. Giving you the endurance to tackle another week of weight loss.

Figure 5. Glycogen levels with 50% calorie deficit vs. metabolic confusion protocol with a 20% calorie deficit and 5% surplus.

4. Balances Ghrelin & Leptin

Ghrelin and leptin are hormones that control your hunger and appetite. At normal levels, they tell you when to start and stop eating in order to maintain your weight.

But dieting throws these hormones out of whack. In fact, 3 weeks of calorie restriction can increase ghrelin by 18% and decreases leptin by 45%¹.

On one hand, high ghrelin levels make you feel hungry more often. While low leptin means you don’t feel full after eating.

This vicious cycle is your body’s way of regulating weight. And it’s what makes normal dieting impossible to sustain.

Figure 6. Ghrelin/leptin feedback loop.

However, studies indicate that leptin levels reflect cumulative energy balance⁵. Therefore, increasing your overall calorie intake with periodic high-calorie days keeps your appetite in check.

In addition, the easiest way to increase ghrelin levels and reduce hunger is to eat frequent, high protein meals.

5. Makes Dieting Sustainable

Last but not least, metabolic confusion helps you be consistent with your diet. This is true for all the reasons we just covered: faster metabolism, more muscle, boosted energy, and less hunger.

But metabolic confusion is also easy to stick with because it’s realistic, not restrictive. And you have the flexibility to indulge a little.

Most importantly, this diet gets results. While you might not lose weight as fast, you will lose weight consistently for months. And that keeps you motivated.

How to Use the Metabolic Confusion Diet

By now, metabolic confusion is probably sounding pretty good. And you might even be ready to try it. But where do you begin?

Here are the 3 basic steps to get started with metabolic confusion:

1. Determine how many calories you burn each day
2. Calculate how many calories you should eat each day
3. Plan your calorie cycling schedule

Each of these steps can be challenging. So, let me explain in more detail.

How Many Calories Do You Burn?

Before we begin, it’s important to realize that the number of calories you burn is equal to the amount of energy you expend. And the calories you burn in a day are referred to as total daily energy expenditure (TDEE).

Furthermore, TDEE is made up of your metabolism and your activity level. Which includes normal activities like walking around as well as any additional exercise.

Figure 7. Components of total daily energy expenditure (TDEE). Note: Actual percentages depend on your body and activity level.

First, to determine how many calories you burn, calculate your resting, or base metabolic rate (RMR/BMR). There are a few different equations for this, but some are not very accurate. The best formula uses your body composition to calculate BMR.

Next, figure out how many calories you burn through activity. Most calculators use a single multiplication factor. But this presents it’s own problems, as your activity level usually changes over the course of the week.

Therefore, it’s better to find your calories for days you workout and days you take it easy. This way, you can get daily calorie targets matched exactly to your activity level.

How Many Calories Should You Eat?

Once you determine how many calories you burn each day, it’s time to figure out how many calories you should eat. And this is where knowing your BMR comes in handy.

As an example, let’s say your BMR is 1,600 calories per day. Also, you burn 2,000 calories on days you don’t exercise and 2,400 on days you do.

Now we can easily calculate your ideal calorie deficit for each day. Of course, your calorie target needs to be less than your TDEE in order to lose weight. But it also must be higher than your BMR to prevent metabolic damage.

Figure 8a. Calorie deficit w/ exercise. Figure 8b. Calorie deficit w/out exercise. Click arrows to scroll images.

The ideal calorie deficit for you depends on you your body and your goals. But generally, it’s a good idea to start with a smaller deficit. Then you always have room to make adjustments after a couple of weeks.

Try My Calorie Deficit Calculator To Find Your Targets

With your calorie deficit calculated, all that’s left is your high-calorie day. Also called a refeed day. As a rule of thumb, just multiply TDEE x 1.05. This gives you a 5% calorie surplus.

Planning Your Calorie Cycle

Now let’s assume you’ve calculated your calorie targets and you plan to workout Monday through Friday. To continue the example, let’s use the numbers in Table 2.

Note: Slide the table left to see all columns on mobile.

Ok, I know there’s a lot going on in this table. So let’s break it down and walk through it one day at a time starting with Monday.

First, I’m going to start your week with a high-calorie refeed day, the idea being to refill your energy stores for the week ahead. On this day you get to eat 2,520 calories. Which is a 120 calorie (5%) surplus.

Next, on Tuesday through Friday, we go down to 1,850 calories. Since these are workout days, you’re burning more calories. Putting you in a nice 550 calorie (23%) deficit.

For the weekend, we lower calories down to 1,700 since you’re not working out. This keeps you in a 300 calorie (15%) deficit.

Then the cycle begins again on Monday.

Figure 9. Example metabolic confusion schedule for M-F workouts.

When you look at this graphically, it’s easy to see how your calorie intake mirrors your energy expenditure. And the gray area represents your calorie deficit.

Also, notice how calorie intake stays well above the BMR line. Which means you’re burning fat while maintaining your metabolism.

When you look at the week as a whole, your cumulative calorie deficit is about 17%. An ideal balance for losing weight without losing muscle.

I would have you follow this plan for 2-3 weeks and monitor your body composition. If you’re not burning fat, we would increase your energy expenditure to create a bigger deficit – not reduce calories!

But remember, this is just an example. Your ideal targets depend on your body, activity level, and goals. That means you need to apply these concepts to your unique situation.

Metabolic Confusion & Carb Cycling

So far, we’ve covered metabolic confusion with regards to calorie cycling. But how many carbs should you eat to lose weight?

It turns out, combining carb cycling with calorie cycling amplifies your results. Lucky for you, I have a detailed article explaining the benefits of carb cycling and how to use it to lose weight.

Take metabolic confusion up a notch by clicking below. Or check out some of my other popular articles.