Back 2 Basics - Calories

It is time we get back to basics! This article is the first of what will be a long series of articles that cover nutrition from the ground up. Understanding the foundations of nutrition is extremely helpful in improving your own. I have taught this ground-up model to a lot of clients over the years and the first part of our conversation usually goes something like this:

Me: “You already know what a calorie is, right?”

Client: “Yea, I understand them pretty well. Calories are in food. Calories have something to do with weight gain, right? Sure, I know what they are. They are…they are…um…”

Haha, exactly! All jokes aside though, most people believe they have a pretty good understanding of the basics of nutrition. However, when it comes to the most foundational concept in nutrition, the calorie, they find it difficult to explain what exactly they know. Calories have become commonplace terminology for most people these days. Everywhere I go, I continually hear people discuss calories in the wrong context. So, let’s take this time to set ourselves straight on what calories are and how they affect our lives.

The Science

A calorie is simply a unit of energy. In fact, it is probably the most commonly used way to quantify energy, aside from watts for electricity. In chemical terms:

1 calorie = the energy needed to raise the temperature of 1 gram of water by 1° Celsius

1000 calories = 1 kilocalorie (1 Calorie)

*We use kilocalories (1 Calorie) to measure the amount of energy in food. It’s safe to assume (unless you are legitimately burning food in a lab and measuring it) that if anybody says the word “calorie” they are referring to kilocalories.

This type of definition is utterly useless to most of us, however a fun fact for anybody who likes to know how we got this specific unit of measurement.

So, how do we reframe this definition to be useful for our weight management goals? Simply put, calories indicate the amount of energy that is contained in the food we eat. This energy, of course, is vital for our survival. If we run out, we die. Just like your trusty cell phone, we need a continual input of energy to properly function. If your cell phone runs low on battery, you feed it electrical energy through a connection to the wall socket. As humans, we re-energize by ingesting biochemical energy in various forms of food.

The Calorie is simply the unit used to measure this biochemical energy. We measure a person’s weight in pounds/kilograms, we measure a person’s height in feet/meters, and we measure a person’s biochemical energy intake in Calories.

The Application

Ok, so we need to energy to live. We eat to obtain energy. We measure that energy in calories. But why do we get fat???

Unlike our cell phone, which will not charge past 100%, the human body adapts to store as much energy as possible. Humans didn’t always have things so great. We didn’t have 3 square meals each day and ice cream to top it off. The human body evolved during a time when food was scarce and difficult to obtain. Therefore, our bodies are extremely efficient at storing energy. It is a cardinal sin of biology to waste energy and our bodies simply do not. So remember:


Because of this efficiency, biochemical energy balance is the fundamental driving force behind increases or decreases in overall bodyfat on an individual. Biochemical energy is the common denominator into which all food sources are broken down. The amount of energy we eat (amongst other factors to be discussed) directly influences total bodyfat, providing us with an accurate and effective model for discussing and planning future changes to the human body. In short, we can all adjust our bodyfat via nutritional manipulation.

Let’s assume, like most people, that the majority of your days are largely the same in terms of your schedule, your activity level, sleep, etc. If we just change how you eat, this is the result:

More Calories Eaten = More Energy Intake

More Energy Intake = More Energy Stored (BodyFat Increase)

So, More Calories Eaten = More Bodyfat Stored

Less Calories Eaten = Less Energy Intake

Less Energy Intake = Less Energy Stored (BodyFat Decrease)

So, Less Calories Eaten = Less Bodyfat Stored

Simple enough, right? Nutrition is a complex topic, which is why it is so widely misunderstood. We will continue to add to this base foundation, however we have just reached our first rule of nutrition:


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