Is there a difference between eating a calorie from fruit and vegetables and a calorie from junk food?

Recently you can look up how companies are trying to say that it doesn’t matter what you eat as long as you are within your daily limit. Whenever companies that try to make money say something I am always skeptical. It sounds reasonable but I am skeptical.

Calories are a unit of measurement for energy.

You may have heard that 1 calorie is is the amount of energy it takes to raise the temperature of one gram of water one degree or that 1 calorie equals 4.184 joules or that 1 calorie in the context of food is really 1 kilocalorie (kCal).

All of these are true and as you can see, it’s all 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:

The calories in food can come from protein, carbohydrates, or fat, which are the three 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 provide the same amount of energy, the way that energy is used in the body differs based on the macronutrient source.

Here is a very simplistic view of how the energy from each of the macronutrients 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 answer, I’ll keep it simple.

Micronutrient differences:

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 do play an important role in your health and well-being.

Micronutrients enable your body to perform daily functions. Some micronutrients are even critical for survival. A lack of micronutrients in your diet will lead to deficiencies which can result in serious health problems over time.

Healthy foods, such as fruits, vegetables, potatoes, and high-quality meats, contain way more micronutrients than junk foods, such as chips, cookies, and candy. You may have heard these junk foods referred to as “empty calories” for this reason.

This is why getting the majority your calories from healthy food is ideal. If you do this, your nutritional bases will be covered and you can still enjoy occasional “junk food” without sacrificing your health.

To recap: a “healthy food” calorie is the same as a “junk food” calorie in terms of energy. Calories differ in their source of macronutrients, which determines how that energy is used in the body. Calories may also differ in their micronutrient (vitamin and mineral) content, which are essential to bodily functions and overall health.


First published on Quora.

Featured image by NordWood Themes.

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