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Medical Author:

Betty Kovacs, MS, RD

Betty Kovacs, MS, RD

Betty is a Registered Dietitian who earned her B.S. degree in Food and Nutrition from Marymount College of Fordham University and her M.S. degree in Clinical Nutrition from New York University. She is the Co-Director and Director of nutrition for the New York Obesity Research Center Weight Loss Program.

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Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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You may sometimes count them, cut them, or curse them, but you always need to consume them. Calories provide the energy that our bodies need to function and keep us moving. The food that we eat and the beverages that we drink provide calories.

Your sources of calories comes from three of the essential nutrients: carbohydrates, protein, and fat. Each of these nutrients has a set number of calories:

• 1 gram of carbohydrates = 4 calories
• 1 gram of protein = 4 calories
• 1 gram of fat = 9 calories

You may also get calories from alcohol.

• 1 gram of alcohol has 7 calories

You maintain your weight by consuming the right amount of calories, gain weight with excessive amounts, and lose weight with an inadequate amount. Your calorie needs are determined by your age, height, weight, gender, and activity level. You can use the Harris-Benedict Equation or the Mifflin-St. Jeor equation to calculate the number of maintenance calories you require. The Mifflin-St. Jeor calculation is best for someone who is overweight or obese. Once you know how many calories you need to maintain your weight, you can determine what it will take to lose or gain weight. When you go above or below your maintenance calories by 3,500 calories, you will either gain or lose 1 pound. For example, if you consumed an extra 500 calories per day, you would gain 1 pound in a week (500 x 7 = 3,500). The same is true for weight loss. This is why every calorie counts when it comes to your weight.

The FDA and United States Department of Agriculture (USDA) regulations require that ingredients be listed in order of their predominance in a food. This means that the ingredient used in the highest amounts will be listed first. This poses a problem when a perceived unhealthy ingredient was the predominant ingredient. For example, when people see sugar as the first ingredient in a cereal, they may be more likely to consider it unhealthy. The way that food manufacturers have gotten around this is to use different sources of sugar in smaller quantities. For example, a food containing 1 cup of sugar may have to have the sugar listed as the first ingredient, but smaller amounts of different sources of sugar could be listed throughout the ingredients.

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