What is in a Calorie?


Calories are your friends. Really. Without them, you won't go anywhere/achieve anything. Trust us. 

I asked my little nephew the other day if he knew what a calorie was and he quickly replied, “It’s what makes you fat.” I didn’t know if I wanted to laugh or cry. While he was technically correct and his response was unknowingly witty and oddly in tune, I also realized that I might have exposed him to too many pro cyclists and that a three year old shouldn't be concerned about his power to weight ratio. I tried to explain that calories don’t make you fat on their own, but eating more calories than you need can. He didn’t seem to really care about what I was saying so we went back to the more constructive task of tearing up pieces of paper for no particular reason.

Still, his answer got me thinking about whether any of us really understand calories. For whatever reason, one of the most commonly asked questions I get asked when I’m at a bike race is, “Hey Al, how many calories do these riders eat?” I’m so sick of hearing that question that my knee jerk response is always something dry like, “A lot more than you.” But, If I’m in a particularly good mood, I might slowly and critically look the person up and down, and respond in a matter of fact albeit facetious tone; “Obviously less than you.”  That answer always seems to leave them even more confused.

So to set the record straight, let’s get some facts on the table:

1. A calorie is a unit of measure for energy just like a centimeter or an inch is a unit of measure for distance.   Specifically, one calorie is the amount of energy needed to raise the temperature of 1 gram of water 1 degree Celsius, whereas 1 Calorie with an upper case “C” is equal to 1 kilocalorie or kcal (i.e., 1000 calories), which is equal to the energy needed to raise the temperature of 1 kilogram (1000 grams) of water 1 degree Celsius. In the United States, food is always represented using the upper case “Calories” instead of Kcals because smart people out there felt that Americans couldn’t handle using the “kilo” or “k” designation. That’s the equivalent to making “Grams” with an upper case “G” synonymous with “kilograms” or “kg.” Everyone else just uses “kcals” or “kilocalories.”

2. I’m not saying you’re fat and I’m very sorry for what I said earlier. Maybe we’re all just affected by misguided societal ideals. Know that if you just focus on your health and happiness the way you look is beautiful to me. In fact, I made you a Christina Aguilera iTunes mix. Listen to that first song because “You are beautiful, in every single way.”

3. Energy can take on many forms from the mechanical work done by a lever or machine, the heat given off by a fire, the radiation given off by a nuclear reactor, and even the sound of a tree falling in the woods that no one hears. In the end, energy is what allows us to exist, to move, and to be something other than a cold inanimate blob of silent nothingness.

4. Really, you’re not fat. Well, okay maybe you could lose a few pounds, but we could all lose a few pounds. We cool?

5. In effect, a calorie is a way to measure heat or the heat that something gives off when it’s burning. To measure the calories or energy in food, scientists literally put a measured quantity of that food in something called a bomb calorimeter and using a whole lot of pressure and oxygen, light a match to detonate that food. The heat given off by that explosion is measured in calories and everyone is happy because they got to blow something up in a lab (lab work is not always so exciting).

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