What it really means to burn more calories than you consume

Q: Can you explain the concept of "burning more calories than you consume" in order to lose weight?

A: It sounds like you're referring to a "calories in vs. calories out" type of equation. First you need to understand that one pound of fat is made up of roughly 3,500 extra calories. So in order to lose one pound of fat, you need to create a caloric deficit of 3,500 calories.

Basically, you can create a deficit of calories in three different ways:

1. Eat fewer calories than you burn each day. Keep in mind that your body burns calories all day long as part of your basal metabolic rate (BMR), because it takes energy (calories) for your body to perform basic physiological functions that are necessary for life—breathing, digesting, circulating, thinking and more. On top of that, physical activity (bathing, walking, typing and exercising) uses even more calories each day.

Example: If you eat 500 fewer calories each day for a week, you'll lose about one pound of fat (500 calories x 7 days = 3,500 calories).

2. Burn more calories than you consume by increasing your physical activity. If you eat enough calories to support your BMR, but exercise more, you'll create a caloric deficit simply by burning extra calories. This works only when you're not overeating to begin with.

Example: Regardless of your BMR, if you exercised to burn an extra 500 calories each day, you'll lose about one pound of fat in a week (500 calories x 7 days = 3,500 calories).

3. A combination of eating fewer calories and exercising to burn more calories. This is the most effective way to lose weight and keep it off. It's much easier to create a substantial calorie deficit when you combine dieting with exercise because you don't have to deprive yourself from food, and you don't have to exercise in crazy amounts.

Example: If you cut just 200 calories a day from your diet and burned just 300 calories a day by exercising, you'd lose about one pound per week. Compare that to the other examples above—you're losing weight at about the same rate without making major changes to your diet or exercise routine. Some people hate to cut calories, while others hate to exercise, so a combination approach allows you to do more of whatever comes easier for you.

As long as you are consistent, your calorie deficit will "add up" over time, and you’ll slim down. It's also important to note that although this math seems relatively simple, our bodies are very complicated and you might not always see the results you expect based on equations alone. Many other factors can affect your weight loss rate along the way.

Written by Nicole Nichols, B.S. Ed. and Certified Fitness Instructor