An Unbiased and Practical Guide to Understanding Calories

I've noticed health and fitness enthusiasts generally fall into one of two camps:

Either

"All calories are the same, bro."

Or

"Calories from [insert healthy food] are in no way the same as calories from [unhealthy food]."

As is the case with most things, the truth lies somewhere in the middle and a nuanced, unbiased approach is needed to better understand this subject.

Let's start with the scientific definition.

What is a Calorie?

Calories are simply a unit of measurement for energy.

You may have heard the following:

• 1 calorie is is the amount of energy it takes to raise the temperature of one gram of water one degree
• 1 calorie in the context of food is really 1 kilocalorie (kCal)
• 1 calorie equals 4.184 joules

All of these are true and as you can see, it’s all just a way to measure energy.

Whether you get a calorie from a fruit, vegetable or ice cream, you’re still ingesting the same amount of energy, so in that sense, the calories are the same.

However, there are important differences in the makeup of those calories.

Macronutrient Differences in Calories

The calories in food come from carbohydrates, protein, or fat, which are the three main types of macronutrients.

• Protein is 4 calories per gram, so a calorie of protein is 1/4 of a gram of protein
• Carbohydrates (carbs) are 4 calories per gram, so a calorie of carbs is 1/4 of a gram of carbs
• Fat is 9 calories per gram, so a calorie of fat is 1/9 of a gram of fat

Although each of these calories provides the same amount of energy, the body uses energy from different macronutrient sources in different ways.

Here is a very simplistic view of how the energy from each macronutrient is utilized:

• Protein calories help to build and repair muscle
• Carbohydrate calories provide energy for strenuous activity
• Fat calories provide energy for mild activity and help you absorb vitamins and minerals

There’s much more to all three, but for the sake of this post, I’ll keep it simple.

Micronutrient Differences in Calories

Foods also contain various micronutrients, which are what we commonly know as vitamins and minerals.

Micronutrients do not contain a significant enough amount of energy to be “counted” in terms of calories, but they play an important role.

Micronutrients enable your body to perform daily functions. Some are critical for survival.

A lack of micronutrients in your diet may lead to deficiencies which can result in serious health problems over time.

Certain foods, such as fruits and vegetables, contain more micronutrients (pound for pound) than others, such as chips and candy.

You may have heard the former referred to as "healthy calories" and the latter referred to as “empty calories” or "unhealthy calories" for this reason.

A Better Way to Label Foods

I personally don't believe "healthy" and "unhealthy" are the best ways to label food because there is an inherent positive or negative connotation in these words which contributes to the bias I warned about.

I also believe everyone's situation is unique, so whether a food is "healthy" or "unhealthy" is very context-dependent.

Is a mango healthy? For many people, yes. If you're allergic to it, no.

Is a donut healthy? If you're 500 pounds, probably not. If you're a starving child, likely at least in the near-term.

I prefer to label foods as "more nutritious" or "less nutritious" based on their micronutrient density because this is a more objective way of looking at the contents of a food.

Now, I'll bring the discussion back to calories and share how I view calories from a practical perspective:

My Practical Approach to Caloric Consumption

My practical approach to caloric consumption consists of 3 main objectives:

1. Energy balance: I consume roughly the amount of calories needed to achieve my weight goal (gain, lose, or maintain)
2. Macronutrient balance: I try to target a rough breakdown of macronutrients within my calorie consumption to achieve my health and body composition goals
3. Micronutrient balance: I try to make sure most of my calories are from more nutritious foods so I'm getting enough vitamins and minerals to support my energy levels and long-term health

Within each of these objectives, there are numerous details I will save for another post.

But one thing cannot be ignored and that is measurement because what gets measured gets managed.

Measurement and Tracking

I've been tracking my calories in one form or another for over a decade so I'm well-versed in measurement.

Before you get started, you must understand that in the real world, you'll never be 100% accurate in your measurement of calories. The best you can do is estimate them with a "good enough to see results" degree of accuracy, which is not difficult.

There are various smartphone apps that help you log your food and estimate the calories, macros, and to some extent micros you are consuming through these foods.

For many years, I used MyFitnessPal because it had the most comprehensive food database. Currently, I'm using Cronometer because it's the best for tracking micronutrients, which is one of my 3 main objectives.

If you've read this far, congratulations. You now have a better understanding of calories than 95% of the population and a framework to start thinking about it in a way that can improve your life.

Feel free to reply if you have any questions or if there's anything you want me to go into more detail about.