Home » All » Nutrition » Calorie Counting & Nutritional Labeling Inaccuracy – Why You’re Not Losing Weight

Calorie Counting & Nutritional Labeling Inaccuracy – Why You’re Not Losing Weight

46207683 - close up of woman hands with calories and vitamins chart on tablet pc, fresh juice

People often say that calories aren’t important and that calorie counting isn’t necessary (not true).

In particular, certain “clean eaters” or “low-carb” advocates support the idea that simply manipulating the carbohydrate to fat ratio (i.e. reducing carbs for fats), will enhance weight loss regardless of the calorie intake.

While the need for calorie counting may not always be necessary, there is no denying that calories themselves are fundamental in weight management.

In this article, I’m going to discuss some of the common reasons people cite when diminishing the importance of calories, particularly focusing on the errors that can arise when calorie counting.

By the end of the article you will realize calories are absolutely fundamental in body composition and health, however, the tools we use when calorie counting can be extremely inaccurate.

A Quick Overview of Calories

Calories play a key role in all aspects of life. There’s no getting away from it that calorie intake versus calorie expenditure plays a key role in fat loss.

In short, if you eat more calories than you burn everyday you’ll gain weight. In contrast, if you eat less calories than you burn everyday you’ll lose weight. Sound simple?


For the clean eaters or low-carb guru’s, the important point to take away from this is that by manipulating carbohydrate intake or restricting certain foods it will be much easier to achieve a calorie deficit, meaning you will be eating/ drinking less than you burn. Apart from reducing total calorie intake, a low-carb diet doesn’t provide some “magical” fat loss fairy.

This concept has tricked many people into believing that calories simply don’t matter, when ironically you are still abiding by the laws of a calorie reduction. Taking a low-carb diet for example, the weight loss is simply being achieved through reduction in calories, as it has just eliminated a main food group (packed full of tasty treats!).

Control Calories and Shred Fat While Eating Fast Food?

Regardless of whether you follow a high carb or low carb diet, if calories and protein are the same then there will be little or no difference in actual weight loss, as demonstrated by several studies.

This has also been highlighted in several documentaries, in particular the famous McDonald’s case study, where the researcher consumed only McDonalds fast food for 30 days. Many would presume that consumption of fast food alone for 30 days would cause excessive weight gain however in this instance it didn’t.

Why you may ask? Well it all comes down to calories of course.

The subject (who in one of these trials  was actually an overweight doctor) was consuming less calories than he was using for daily activity and therefore successfully lost weight. More surprisingly, he also improved some markers of health.. because he lost fat! Don’t get me wrong, I’m not advocating a fast food diet, however, it just shows you the importance of calories in fat loss and even health!

calorie counting

Common Food Intake & Calorie Counting Errors

So, why is it that so many people struggle to lose weight even when calorie counting?

The primary issue is that people aren’t actually in a calorie deficit.

Even if you believe you are an “expert” calorie counter, I almost guarantee these issues throw you off by 20-30%:

  • General miscalculations when tracking,
  • Errors in the nutrient and food labeling information (yes, they are often inaccurate!),
  • Changes in your  daily metabolism,
  • Daily Non Exercise Activity Thermogenesis (NEAT) and other activity levels,
  • Differences in your work out sessions (i.e. leg days vs arm days vs cardio),
  • Errors in the smart phone tracking application or tracking method,
  • Changes in the calorie yield during digestion (i.e. some foods provide less or more calories once digested).
  • Errors in estimating your calorie needs or resting metabolic rate.

Ultimately, there are a ton of factors and variables that play a key role in your daily metabolism, energy expenditure and energy intake.

Outside of a lab based setting, it is extremely hard to accurately calculate total calorie expenditure or your resting metabolic rate and it’s even harder to accurately calculate (i.e. within 10%) total food intake.

Here is a closer breakdown and discussion of these issues. By becoming aware of them, you will quickly see why your ‘predicted’ intake can be off by 20-50%!!

Food Label Inaccuracies

One of the biggest issues when calorie counting relates to the accuracy of food labels.

Even if you log every single food accurately in accordance with the labels, these calculations can be off by as much as 20%. This is particularly prevalent for whole food based products where nutritional values are calculated approximately.

By law, food labels must be within a 20% margin, while 20% may not sound like much it can equate to a huge 400-600 calories inaccuracy per day.

So, as you can see even if you record all of your food extremely carefully the simple errors in the nutritional labels and the information on packets and supplements can massively throw you off track.

You must consider, that your daily deficit or the amount of calories you reduce your daily intake by per day is maybe only 20%. Therefore, even if you’re reducing calories or calorie intake noticeably, that might be neutralized by the errors in the nutritional value on labels.

In addition to these general errors on labels, there are so many other factors you must consider when calorie counting.

Food Prep & Metabolism Alters The Calorie Content

Another example is the alterations of calories when preparing foods, particularly whole foods.

For example, when cooking meat, fish or vegetable based products the water content can change drastically depending on the cooking method.

In addition, you must remember that at one point the food you are eating was a living organism, therefore, it too would have had different ratios of fat, muscle and water content, which again will alter the amount of calories and nutrients it provides.

Furthermore, some studies have highlighted that the food you intake may not provide the same amount of calories after digestion and absorption.

One great example of this is nuts and seed intake when compared to the exact same serving size of nut butter or seed butter. Research has shown that when you consume whole nuts, due to their complex nature and breakdown process you actually obtain less calories than is listed on the label. Importantly, you obtain less calories than the exact same serving and gram size of nut butter.

Similarly to the individual variances in foods, protein, carbohydrate and fat will alter the absorption and energy yield once cooked, digested, and metabolized.

We all know that protein is extremely hard to break down into energy, which is one reason it helps with weigh loss and reducing hunger.

For protein, around 25% of the calories you intake are ‘burnt’ or ‘lost’ just in the cost of energy production and metabolizing the food for usable energy. However, you compare this to carbohydrates and fat, only around 5% to 10% of the total intake is actually lost during metabolism and energy production.

As you can see, within the three macro nutrients alone there is a large variance in the amount of energy each one provides once it’s been digested and is in the body.


Poor Calorie Reporting

In addition to the errors in basic nutrient labels, there’s likely to be a large error in the accuracy of your calorie counting.

Even if you are very experienced at calorie counting, there’s a good chance that you are less accurate than you believe (no offense!).

For example, a group of trained dieticians who had undergone a four year degree, designed meal plans everyday, tracked food intake with patients for years were put to the test. In the study, they had the dietitians monitor food intake to see how accurately they were, against the the most accurate gold standard method.

This study really highlighted the drastic differences between food intake and actual values recorded. They compared their written and manual recordings in a metabolic chamber which is the gold standard method for measuring calorie intake.

To everyone’s surprise, they found that on average the dieticians recordings were off by a huge 30% !!!

As mentioned previously, 30% is a drastic difference that would easily throw off any weight loss efforts. Remember you’re probably only reducing calories by 20% maybe 30% per day which can easily be neutralized by this misreporting.

If you then combine this reporting issue and errors in food labels, the food intake error margin could be as high as 50% which for some people would be another 1500 calories a day!

Now don’t get me wrong, these two combinations are at the extreme of the scale however, you can quickly see how your calorie counting process can easily be thrown off even when you have great intentions and experience.

Daily Variations In Metabolism & Energy Output

So far, we’ve seen that your intake can be off by up to 50% when you combine errors in reporting and errors in nutrient consumption and nutrient/ food labeling.

However this is only half the picture, there are still a ton more variables on the other side to consider.

The other side of the equation of course is calorie expenditure, which can be drastically altered by your daily lifestyle and daily routine.

Even if your sleep and wake times are exactly the same each day, changes in your daily movement, outside temperature, brain concentration levels, exercise, stress, supplementation and much more can all affect your daily metabolic rate.

Therefore, on a daily basis your energy expenditure may greatly vary without little change to your actual routine.

On top of this, one of the greatest changes to energy expenditure is of course exercise. For example, if you were to compare a training day versus rest day there may be over a thousand calorie shift when you combine the calories burned within the session and then the elevated metabolic rate after the session.

Your daily exercise routine obviously plays a very large role in your metabolic rate and calorie expenditure. Even if you were to compare an arm session or a cardio session or a leg session the calorie expenditure can be 200%-300% different for the leg session compared to the less strenuous arm or cardio session.

In addition to structured exercise, research has highlighted that your Non Exercise Activity Levels (NEAT) varies massively from day to day. NEAT describes all exercise and activity that is not part of a structured routine, i.e. any time you move outside of  the gym.

Several studies have shown that just daily changes in your routine even the amount of sleep you get per night can affect how much energy you burn during that day by up to 700-1000 calories.

If you think about it logically, someone in a manual or strenuous based job such as a builder, waiter or manual laborer compared to someone sitting at a desk for eight hours can cause large variances in calorie expenditure.

Even the same person in the same job, could one day  be sitting at a desk for eight hours and the other day be walking or moving about, this could cause a change in metabolic rate and energy expenditure by 300-400 calories just between days.

Hopefully, you can now see that there are large variances in your energy expenditure which must then be added to the large variances and changes in your energy intake.

Stop Worrying About The 10%

Clients and fans will often message me worrying because they’ve been off by 50-100 calories or off by 5-10 grams of carbs, protein, or fat per day. Every time I get this question (which is on a weekly basis), I try to explain the factors above, can make much larger differences than 10% on their own.

Therefore, obsessing over 100 calories or 10 grams of carbs makes absolutely no sense, when your daily intake can already be off by 20, 30, 40, or maybe even 50%.

This also applies to people on my 90 Day Bikini Transformation Program, who will ask me do they follow meal plan A or meal plan B which may have 10 gram or 100 calorie difference in macro and calories. Again, I explain these factors, emphasizing that following calorie and macro plans is really just a more accurate guesstimate than eyeballing your food intake or eating with no kind of structure or portion size control at all.

Hopefully now we’re coming to the end of this article, you too will have changed the way you look at tracking your calorie and food intake. My point is to just relax a little, focus on the basics and adjust as you go.

Establish a Starting Point & Keep Adapting 

It’s great to set a calorie food intake, and I still recommend it, but you must realize that this is still just an approximate starting point.

Even when I track my own intake, with my metabolism being measured in a laboratory based setting and nearly a decade of experience in tracking energy expenditure and energy intake, I always expect to be off by 10%, if not 15 – 20%.

One piece of advice I often emphasize, is to just err on the side of caution.

For example, if you’re trying to lose weight then it’s better to be slightly under (i.e. 10% less than what you may normally plan) as this allows for 20%-30% variance. In contrast if you’re trying to gain weight, it’s probably better to eat 10% more than you think just to ensure that you actually hitting a calorie surplus.

You can clearly see here, why calories still matter and how people simply become confused into thinking they don’t. It’s not that calories don’t matter, it’s simply that you may not be tracking them as accurately as you would like to believe.

Sure, you can cut carbs and lose weight. You can also stop eating after 2pm and lose weight. You could even fast and eat nothing until 1pm. Are any of these techniques magical? The answer is no. What do they all achieve? Reduced food intake and therefore… reduced calorie intake!!

Not Losing Weight? Maybe This is Why?

This article is also key if you’re not losing weight, highlighting the fact you may just be misreporting.

People will often message me saying “I’m tracking everything I’m in a calorie deficit no matter what I do I cannot lose weight”. However, as you can now see they probably aren’t in a calorie deficit, even if they believe they are…

When dieting, it’s very easy to ignore snacks, larger portions and to simply decrease your energy expenditure by moving less, finishing early in the gym or skipping gym sessions.

In addition to this, I’m constantly discussing the changes in metabolism and energy intake that occurs when dieting. You can read more on this HERE, however, basically your body will go into power saving mode and try to reduce its daily intake to accommodate for the calories you’ve cut from food.

If you struggling to lose weight successfully, take another read of this article and start to think about what errors could be creeping into your daily calorie counting and expenditure calculations. Chances are, somewhere an aspect isn’t being monitored or recorded as well as you believe.

While the calorie in versus calorie expenditure equation is simple, the factors that can affect this balance are from it!

Remember, calories always matter, however, your calorie intake and expenditure may be far harder to track accurately than you had once believed.

Enjoy this article? Share it with a friend and help them achieve their goals by clicking below…

About the author

Rudy Mawer, MSc, CISSN

Rudy has a 1st class BSc in Exercise, Nutrition & Health and a Masters in Exercise & Nutrition Science from the University of Tampa. Rudy currently works as a Human Performance Researcher, Sports Nutritionist and Physique Coach. Over 7 years he has helped over 500 people around the world achieve long last physique transformations.

He now works closely with a variety of professional athletes and teams, including the NBA, USA Athletics, World Triathlon Gold Medalists, Hollywood Celebrities and IFBB Pro Bodybuilders. If you would like to get in contact or work with Rudy please contact him on social media.

View all Articles by Rudy »

Follow Rudy on Facebook >>

Follow Rudy on Instagram >>