From Jennifer R. Scott,
Your Guide to Weight Loss.
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The official definition of a calorie is "...the amount of heat needed to raise the temperature of a liter of water 1 degree (DHHS)." But if that's a little too scientific for you, think of it this way...

A calorie isn't actually a tangible thing, it's a unit of measurement.

A calorie measures the energy in food and beverages we take in. We all need that energy to live. Everything we do relies on the energy that comes in the form of calories.

The food we eat becomes the fuel that runs our bodies. Drinks also contain calories; sodas, for example, are referred to as "empty calories" meaning they carry no other nutritional value; but the calories definitely still count.

No matter the form of your calories ... if you "overload your tank" you will find yourself gaining weight.

Understanding caloric needs is an integral part of weight loss. Research over the years has proven -- whether diets focus on fat or carbs -- that calories still count. Why? Regardless of what diet you're following, if you take in more calories than you need ... you gain weight.

The daily recommended caloric intake for the average American maintaining their weight is 2,000 calories, give or take a few: Men can eat a little more, women, less. Your specific, individual calorie needs depend on several factors such as your activity level and metabolism.

Where are Calories?

Calories are found in four components of foods. They are: fat, carbohydrates, protein and alcohol (i.e., sugar). Fat contains twice the calories of carbohydrates or protein.

Ct'nd: Is a Calorie a Calorie? >>

Learn more about counting calories and search for the caloric content of all your favorite foods at Calorie Count Plus!