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Why Tracking and Counting Calories Does Not Work - Part 1

There is no shortage of myths in health, fitness and weight management. At the top of the list stands the calorie balance equation. Often, you read and hear from “experts” who tout the solution to weight management as “eat less, move more.” This phrase is used so often and with such confidence that most people would think it’s been proven. That’s not the case. The body doesn’t function in a way that allows people to change their body composition simply by eating fewer calories or burning more through activity and exercise.

Being it’s January, many people have a renewed focus on shedding extra body fat. Statistics say, only one in six people will have any success with losing and keeping weight off, and when they do, it will only be 5% of what they originally lost. Though this seems like a pretty low chance of success for most people, I hope you’re not “most people.”

You should know there is a way to reduce body fat and keep it off for the long-run. However, the solution is not in any way, counting the calories you eat, and trying to track the calories you burn throughout the day, every day for the rest of your life.

To fully appreciate how flawed the concept of “calories in, calories out” is, we’ll have to touch on some technical information. I’ll try to keep it as high level as possible, but I want you to also finish the blog post thinking “how the heck does this idea keep getting repeated?!” In an upcoming blog post, I’ll talk about a different frame of reference to use in looking at the food you eat and the activity you add to your lifestyle.

What is a calorie?

A calorie, as we often see it on a nutrition label, is actually a kilocalorie. To make it simple for consumers, it became a Calorie with a capital C, and since then has been used so often without the capital C that we just use calorie. The true Calorie, or kilocalorie, is a measure of the energy required to raise one kilogram of water one degree Celsius. Originally, the calorie value of a food was determined by burning it, but today an assumption is made based on the protein, carbohydrate, fat and alcohol content of a food. These values are rounded according to the following table:

Again, these numbers are not exact. One of the reasons they’re not precise is because a certain amount of energy is required to break down and absorb these macronutrients. After accounting for the energy expended, a gram of protein provides about 3.2 calories, a gram of fat 8.7 calories and a gram of carbohydrate, 3.8 calories. These numbers are not exact either, because different forms of each of these macronutrients require varying levels of energy for digestion. Whew, that’s a lot of explanation to say the calorie counts on foods are really just estimates.

The 3500 Calorie “Rule”

You’ve likely heard that “in order to lose a pound of fat, you have to burn 3500 calories more than you consume. One pound of fat is 16 ounces, or 454 grams. According to the table above, 448 grams of fat equals 4086 calories. How do we get 3500 instead of 4086? In the body, fat, or adipose tissue, is not 100% fat the way you’d expect a bottle of olive oil to be 100% fat. It is about 87% fat (another estimate), so 87% of 4086 is 3554.86. Rounding to a more simple number, 54.86 calories are dropped from the “3500 Calorie Rule” to land at 3500 calories.

If you did not see all the estimates in the past few paragraphs, read them over again. Even if the "calories in, calories out" concept worked, the math wouldn’t work because there are so many variables involved.

Counting Calories In

Let’s say the 3500 calorie rule was in fact accurate. The next step would be to accurately track what one consumed and what one burned for energy. We already mentioned the calculations for fat, carbohydrates and protein are estimates, not precise measurements. This becomes even more complicated when you consider the variability of the foods we eat. A piece of grass-fed beef usually has less fat by weight than the same cut from a conventionally raised cow. If it has less fat by weight, it will have more protein. For the same 8 ounce piece of meat, it would have less fat and more protein, and fewer total calories. How much less? You’re can’t be sure, unless you actually test the meat. But then you wouldn’t be able to eat it, so you’d need to get another cut of beef that wouldn’t be exactly the same, so you wouldn’t know the calorie value of that piece of meat either.

Let’s pause here for a moment. If you were truly going to gain an extra pound of fat by eating 3500 calories more than you burn, you’d only need to eat 116.66 calories per day more than you burn in a 30 day month to gain a pound of fat. That’s 38.88 calories per meal if you eat three meals per day. Even if you weighed and measured every bite of food you put in your mouth, you’d still never be able to manage your calorie intake accurately enough because the whole idea of the 3500 calories and the calorie value of the macronutrients are based on so many assumptions and rounding of numbers!

Remember, the calorie balance equation assumes that you must maintain a precise balance between the number of calories you consume and the number you burn. If the calorie balance equation were true, and you eat 38.88 calories per meal too many, you’ll gain twelve pounds of fat per year. How can you get to precision of 38.88 calories when everything above is based on so many assumptions and rounding of numbers?

Counting Calories Out

Accurately counting calories is in is nearly impossible. What about calories out? The energy one burns comes through resting metabolic rate, daily activity, exercise and the production of heat. Resting metabolic rate is the energy the body requires just to maintain normal function, tissue repair and keep you breathing while at rest. Resting metabolic rate makes up the majority of energy the body burns during the day and can be easily tested through a resting metabolic assessment. When one’s metabolic rate is higher or lower than normal, it can be an indicator of metabolic dysfunction. The body also tends to increase its metabolic rate when it gets enough calories and nutrients, when under acute stress or if recovering from trauma like an injury or an intense workout. It lowers metabolic rate when energy is restricted, such as a typical low-calorie diet, or when under chronic stress.

The brain uses the largest amount of energy during the day for its size, but muscle tissue is the most metabolically active tissue you can modify through exercise and nutrition. Adding more muscle to one’s frame can slightly increase resting metabolic rate. Another myth is the idea that a pound of muscle burns 50 calories per day. It's actually only about six calories per day, but it is still the most metabolically active tissue you have control over. Of course, the loss of muscle tissue can slow it as well.

The calories one burns through daily activity vary from person to person. Those with desk jobs tend to burn fewer calories than those who perform manual labor. The body is pretty smart though. When people are very physically active during the day, resting metabolic rate can be reduced to conserve energy. When they’re less active, assuming they have a healthy metabolism, metabolic rate may go up to burn off some of the energy that isn’t being used.

Interestingly, a well-known weight loss company recently added an activity monitor to their program, with the idea that people can earn the ability to eat more by moving more. The program is based heavily on the concept of the calorie balance equation. There’s no evidence to suggest that when people increase the number of steps they take during the day, they should eat more.

At Life Time, we also promote the use of an activity monitor, with the focus on getting 10,000 steps each day. However, the 10,000-steps-per-day goal is not for increasing calorie expenditure. Instead, we believe in the importance of movement simply to improve the health of one’s metabolism. Moving more helps the body use fuel properly, rather than helping it burn more total calories.

Exercise is a third way calories are expended during the day. Workouts are a very minor part of the total calorie expenditure for the average person. Professional athletes train for hours every day, but for most of us, our exercise sessions last about an hour, three to six times per week. The number of calories one burns in an exercise session is not important. What I find interesting is that research has shown, those who burn the most calories during an exercise session also have the strongest appetite later in the day, or they feel the most worn out. The body knows it should save some energy later in the day, or eat more, to compensate for the demanding training session. I've also seen this from personal experience in working with people.

Exercise, or training sessions, should be designed in a way that improves range of motion, increases coordination, stimulates the growth of muscle tissue, or helps your body become more efficient at using fat for fuel. Each of those four goals improves one’s health, metabolism, performance or endurance. If the goal is simply to burn as many calories as possible, it can lead to workouts that increase cortisol, the body’s main stress hormone. These high-intensity exercise sessions also drive cravings for sugary foods or decreases activity the rest of the day. The increased appetite or fatigue are ways for the body to help maintain glucose levels. Interestingly, when people train at an intensity level that allows them to use more fat for fuel, rather than carbohydrates, cravings are not nearly as significant and they are less likely to feel so fatigued afterwards.

If the “calories in” side of the equation could be accurately measured (we already said it can’t), what is the likelihood we could precisely account for the energy we expend each day? It would also be nearly impossible. Think about this for a moment. If we were to move around a little too much each day, so that we burned an extra 116.66 calories more than we consumed, and did it for 10 years, it would mean we’d lose 120 pounds during that time. For me, that means if I move around too much, I’ll be 60 pounds by the time I’m 55 years old. If I err on the other side of the equation and consume 116.66 calories too many each day, I’ll be 300 pounds by the time I’m 55 years old, and 420 pounds by my 75th birthday.

Thinking logically, the calorie balance equation just doesn’t makes sense. Hopefully those reading this will help to spread the word about how silly and unsupported the concept is.

To recap where we’re at so far,

  • The calorie values of macronutrients are estimates, not perfectly accurate measurements.
  • Macronutrients vary from one portion to the next of the same food, making the calorie assumption less accurate.
  • A pound of fat, on average, contains 3554.86 calories, not 3500. However, the 3554.86 is based on another estimate that says a pound of human fat tissue contains 87% lipids.
  • Even with weighing and measuring food, it would be impossible to accurately determine exact calorie levels of a meal. Few people would be willing to weigh and measure everything anyway.
  • Resting metabolic rate varies significantly, and is the major contributor to the calories people burn on a given day. It’s valuable to measure one’s metabolic rate to see if it’s well outside a normal range, but attempting to prescribe calorie recommendations from the assessment would provide inaccurate daily calorie targets.
  • The body can adjust its metabolic rate to balance out energy burned through daily activity and exercise. When one does not consume enough usable energy, but increases physical activity, metabolic rate may slow down to compensate, or hunger and appetite increase.

If you still think counting calories is a long-term solution to weight management, I recommend picking up Zoe Harcome’s new book, The Obesity Epidemic. You’ll be shaking your head at the idea that you ever believed the calorie balance equation was a solution to weight management.

The points above lead to the following questions:

  • If metabolic rate slows down when an individual follows a typical low-calorie diet, or when an individual increases activity, how is weight lost?
  • Is there a difference in the types of food one can consume and the effect it has on fat or carbohydrate utilization?
  • Is it possible to reduce the energy one consumes without slowing metabolic rate?
  • If weight loss isn’t about decreasing calories in or increasing calories out, then what’s it about?

We’ll look at the answers to these questions next week. For now, share your thoughts and comments below.

Written by Tom Nikkola – Sr. Director of Nutrition & Weight Management

This article is not intended for the treatment or prevention of disease, nor as a substitute for medical treatment, nor as an alternative to medical advice. Use of recommendations in this and other articles is at the choice and risk of the reader.

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