Should You Track Calories on Keto?

Many find low-carb or keto almost magical in the early days. As they move away from the most hyperpalatable fat+carb combo foods, they experience greater satiety, their blood sugars and insulin levels drop, and they feel great.

High-fat foods can also feel satiating, but this may be simply because they quickly provide you with a lot of energy.  Many popular low-carb or keto foods contain plenty of bioavailable protein, so they get a great satiety response. Folks are suddenly able to manage their food intake without having to fight against their appetite.

It’s no wonder that, after trying to count calories and restrict, once they switch to a low-carb diet, they start to believe that calories don’t matter.

But the problem comes when they also think fat is a ‘free food’ and steer the ship towards more refined fat rather than whole-food protein sources, believing that it’s all about keeping insulin low rather than energy balance.  Unfortunately, most people don’t get away with unlimited added fats like cream, butter and oil while continuing to lose body fat over the long term. 

But when keto fails, is counting calories the next logical step?  And if not, what else can we do to continue our fat-loss journey?

The Problem with Counting Calories

In the end, energy balance still matters.  All calories count, but only if you can accurately count all the calories going in and coming out.  

However, the reality is that energy is hard for us to balance simply by counting calories with a smartphone app paired with our fitness trackers.  Our ability to track calories in and calories out accurately and reliably makes it extremely hard and frustrating for most people. 

  • Counting calories may be fine if you’re a single bodybuilder who can pre-prepare everything.  But most of us live unpredictable lives with family dinners, work lunches and impromptu parties that make it impractical to weigh and measure everything we eat all of the time. 
  • While we can be disciplined most of the time, it’s those occasional meals (when your calorie tracking app isn’t looking) that undo all your hard work. 
  • Even if you were able to weigh and measure EVERYTHING you ate, the data in your app rarely matches the foods you are eating. 
  • Your body doesn’t ‘burn’ the food the same way that calories are measured in a bomb calorimeter (shown below). 
  • Your calorie tracking app doesn’t account for the thermic effect of food, which changes depending on the macronutrient profile of your food and the degree of processing.
  • Foods that are more processed tend to be easily digested, while foods that are less processed are more likely to be digested slowly and keep us feeling fuller for longer or be excreted. 
  • Any calorie target from an online calculator is going to be inaccurate.  Your metabolism is complex, and the number of calories you require depends on various factors, including your muscle mass, exercise, stress and sleep (not to mention pandemics and lockdowns, which restrict your movement).
  • Your energy expenditure changes from day to day.  If you try to maintain a fixed calorie intake, there is a serious risk that your healthy appetite signals will become dysregulated as you try to push through hunger some days and overeat on others.  
  • When you suddenly slash your energy intake, your body quickly adapts to survive. Your metabolic rate slows. You produce less heat.  You feel less energetic, and your involuntary activity will reduce.  You ‘burn’ fewer calories day to day than you used to.  
  • Any estimate of your energy expenditure that you get from your FitBit or Oura ring is only an estimate and is likely to be highly inaccurate.  People who rely on these devices to estimate their calorie expenditure are more likely to gain weight because they tend to congratulate themselves and eat back the calories the app has told them they burned.
  • When you count calories, your focus remains on how much you can eat rather than listening to your body’s hunger signals, which tell you when you need to eat.
  • Simply counting calories teaches you nothing about food quality and a sustainable eating pattern that will lead to long-term health. 

Eating should be impulsive and instinctual. Your body drives your appetite to ensure you seek out the nutrients you need.  However, it also means that, despite our best efforts to limit the amount we eat, our appetite usually wins out, especially if we continue to eat the same food that led us to be overfat in the first place. 

So, while energy is always conserved, the factors on either side of the calories in vs calories out equation are incredibly complex and beyond our ability to manage accurately. 

Calorie Tracking Can Cause You to Develop an Eating Disorder

If you’ve ever tried tracking your calories, you will understand that your reptilian brain doesn’t like to relinquish control of your appetite to a smartphone app.  As shown in the image below, your brain is divided up into three portions. 

  • The neocortex is the rational or thinking part of our brain.  This is the logical part of your brain that makes plans to lose weight and eat less using the latest technology.
  • The limbic brain is the part that feels emotions (which may not always appear logical or align with what your neocortex is thinking).
  • Then we have the reptilian brain, which looks after basic survival functions like breathing, temperature control and eating. 

While calories in vs calories out sounds seductively simple, your reptilian instincts fight for control when awoken by the threat of starvation!  It’s critical to keep your ‘inner lizard’ fed with high-quality food, so it doesn’t sense an emergency and stays asleep. 

Many people become anxious when they put so much effort into tracking everything they eat and don’t get the results they hoped for.  Sadly, food tracking can drive an unhealthy neurosis in many people.  

A 2017 study of people with a diagnosed eating disorder found that 75% of participants reported using MyFitnessPal.  Disturbingly, 73% of the MyFitnessPal users said that their use of MyFitnessPal had contributed to their eating disorder. 

Hopefully, you can see by now that simply counting calories and trying to stay under some arbitrary target using self-restraint while continuing to eat the same foods doesn’t end well for most people. This is why it’s essential to prioritise nutrient-dense high-satiety foods to enable you to manage your appetite.  

Precision vs Accuracy in Food Tracking

While food tracking is rarely accurate and reliable, it can still be helpful if we understand its limitations.  To help explain what I mean by this, the image below shows the difference between accuracy and reliability.  

Let’s consider the target in the top left (i.e. accurate and reliable).  It is unlikely you’re going to be perfectly accurate and reliable in your food tracking (top left target) at the same time due to the inaccuracies related to food labelling and measurement.  This is what most people expect from their tracking, but it just doesn’t occur in the real world.

A bodybuilder preparing for a contest who weighs and measures everything they eat and consumes a regimented diet may be inaccurate and reliable (bottom left corner).  They will be eating similar things day to day, week to week, with slight modifications to make sure they keep moving forward.  Even though their estimation of calories is not accurate, they are reliable, so their food tracking data is valuable. 

Most people who are tracking their food intake will be inaccurate and unreliable (bottom right target).  While not as powerful, this data can still be useful so long as you can update your target macros based on your actual progress in terms of fat loss, blood sugars and retention of lean mass.   

Note:  Developing a regular eating routine with an appropriate level of variety is helpful to maximise sensory-specific satiety.  Constant novelty and variety will cause you to eat more, making it harder to be reliable or accurate. 

Why Managing Macros is More Useful than Tracking Calories

While trying to stay under some arbitrary calorie target is a fool’s errand, it may be useful to track your macronutrients (i.e. carbs, fat and protein). Together with your biometric data (i.e. weight, body fat and blood sugars), you can use this information to ensure you continue to move towards optimal metabolic health. 

  • If your blood sugar regularly rises by more than 1.6 mmol/L (or 30 mg/dL) after meals, then it’s likely you are eating excessive amounts of refined carbohydrates and need to adjust your carbohydrate limit.
  • If you are losing excessive amounts of lean mass (i.e. muscle), then you likely need more protein.
  • If you are still not losing weight, then you likely need to dial back your dietary fat intake to ensure fat is coming from your body rather than your plate or coffee mug.

For more details on our Smart Macros Algorithm, check out the article Why set and forget calorie targets will always fail you (and how Smart Macros Algorithm can help).

What to Do When Weight Loss Stalls

  • If you have stopped making your desired progress, we recommend people try Data-Driven Fasting, using the blood sugar meter as a fuel gauge to be sure to achieve a negative energy balance (without counting calories).  This is simple and effective for most people, with the minimum investment of time and effort and avoids the hassle of food tracking. 
  • For those who find their blood sugars are super stable but are still not seeing weight loss, we recommend checking their macronutrient profile by tracking in Cronometer for a few days.  If your goal is fat loss, you can work towards a 40% protein.  If your blood sugars are already stable, this can be achieved by dialling back dietary fat while focusing on nutrient-dense foods. 
  • If you’re looking for guidance on how much protein and fat you should be eating, you can use this simple macro calculator as a starting point. 
  • If you’re motivated to track your food, you can use our 7-Day Nutrient Clarity Challenge to review your micronutrients and identify the foods and meals you should focus on to achieve your goal.   

Get your copy of Big Fat Keto Lies

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