What Is A Calorie And Why Is It Important To Know How Many Calories There Are In Certain Foods?

Keith Ayoob answers the question: 'What are Calories, Why Do They Matter?'

ByKeith Ayoob, Ed.d., R.d., Associate Clinical Professor Of Pediatrics, Albert Einstein College Of Medicine
December 22, 2008, 3:55 PM

February 1, 2009 -- Question: What is a calorie and why is it important to know how many calories there are in certain foods?

Answer: A calorie is actually a unit of heat energy. That's right. We think of calories as just things that are in food and all foods have calories. But your body sees calories as energy and it's energy to produce heat. And heat energy is what really fuels our body just the same way that gasoline is what fuels your car's energy.

Now all foods have calories and different foods have different amounts of calories. Calories are provided by fat, carbohydrate, and protein.

Fats have the highest concentration of calories. That's nine calories per gram of pure fat. Protein and carbohydrates each have four calories per gram of pure protein or pure carbohydrate. Alcohol, pure alcohol, has seven calories per gram. So understanding the role of calories in your diet can help you balance your calories in with your calories out, and help you achieve weight management goals.

Now you can look at, find out the calories in foods by looking at the calorie label or the nutrition facts panel on packages of processed foods. They will all have the number of calories per serving and the portion size per serving. And using these tools, you can help yourself estimate how many calories you're taking in per day and help you achieve your weight loss goals.

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