By Lindsey Joe, Registered Dietitian Nutritionist

Guys, it's time we had the talk... and by that I mean the calorie conversation. There's a lot of confusion out there about calories, so let me break it down for you in a simple way.

Calories are actually just a unit of measurement. Calories measure the amount of energy in foods and beverages as well as energy our bodies use—whether it's energy to breathe or energy to run a marathon. So, calories = energy. We all need energy.

Calories equal energy

Calories are found in practically everything except water. So, everything provides your body with energy. But what determines the difference between calories in one food versus another? (Hint: It's not the "food gods" deeming donuts high in calories and celery low in calories.)

Nutrients determine the calorie count in a particular food or beverage. There are three main nutrients found in all foods:

  1. Carbohydrates,         
  2. Protein, and
  3. Fat.

A food can contain one or a combination of these nutrients. Each of these nutrients contributes different amounts of calories: carbohydrates and protein have four calories per gram, while fat has nine calories per gram (making it the most energy-dense nutrient).

Let's think about a small apple for example. It contains 80 calories. The main nutrient found in an apple is carbohydrates (in the form of fiber and sugar). Like most fruits, an apple does not contain protein or fat. So, the calories contained in a small apple are all coming from carbohydrates, an essential nutrient and the brain's main source of fuel.

Now let's think about 1 tablespoon of olive oil. It contains 120 calories. The main nutrient found in olive oil is fat (in the form of monounsaturated fat). So, the calories contained in 1 tablespoon of olive oil are all coming from fat, also an essential nutrient. Note, however, how much smaller 1 tablespoon of olive oil is compared to the small apple. It's because of olive oil's fat content that it contains so many more calories.

Where are your calories coming from?

So, the truth is that a calorie is a calorie. A single calorie from an apple will give you energy just as a single calorie from olive oil will. But there's more to weigh here.

When you're making food decisions, asking, "How many calories is this?" isn't the only question you should be considering. Another question you should be asking is, "Where are the calories coming from?"

How you fuel determines how you feel. A fresh apple (that contains fiber and natural sugar) is going to feel very different than an apple pie (that contains a lot of added sugar and fat), and give your body different nutrients. If you're eating well-balanced meals according to MyPlate, the majority of the calories you consume should come from carbohydrates, followed by protein, and then fats.

So remember, all foods and beverages give your body different amounts of calories (a.k.a. energy). But where those calories come from can greatly impact your health and overall well-being.

Fuel on!

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