Are Calories Important When Trying To Lose Weight?

You may have heard that carbs are your enemy or that the path to a slimmer waistline lies in banning fat from your plate. While there is some truth behind the idea of "good" vs. "bad" carbs and fats, the U.S. Department of Agriculture's 2010 Dietary Guidelines points out that you don't have to completely eliminate any food from your diet in order to practice healthy living or promote weight loss. That's because the not-so-secret truth about weight loss is that it's all about balancing calories.

The Math Behind the Burn

Calories, or Kcalories, to be more specific, simply measure energy. They're like the gasoline and your stomach is like the gas tank. Unlike your car, your body can store fuel -- and it does so very well. Those energy stores are your fat stores. In order to lose that fat, you have to use it up -- but you can't just stop eating. That means you have to use up the calories you eat, then start using the stores fat. It takes 3,500 calories burned in addition to what you eat to lose one pound. No matter what you eat or how much you exercise, the math remains the same.

Creating a Caloric Deficit with Food

The U.S. Centers for Disease Control and Prevention calls the persistent state of eating and burning the same number of calories per day "caloric balance" and when you're in a state of caloric balance, you maintain your weight. If you want to lose weight, one way to tip the balance in your favor is to eat fewer calories than you burn. The Mayo Clinic's calorie calculator can provide your caloric balance point. From there, subtract 100 to 200 calories from your daily diet each week until you achieve a steady 1 lb to 2 lb weight loss.

Creating a Caloric Deficit with Exercise

The other way to shift caloric balance into a caloric deficit is to burn more calories through activity and exercise. If you exercise enough to create a caloric deficit, you don't have to significantly change your diet to achieve results. The American College of Sports Medicine recommends 150 minutes of physical activity per week. The exercise doesn't have to be difficult or strenuous, either. For example, if you weigh 185 lbs. and take a 30 minute walk five days per week, you'll burn 1,000 calories and shed 1/3 lb. of fat per week from that one simple change.

Combining Exercise and Calorie Restriction

While it's true that you can lose weight from either cutting your calories or adding exercise to your routine, if you do both, you can double your results. For example, if you cut 250 calories from your daily intake and exercise to burn an additional 250, you'll lose 1 lb per week. The CDC recommends losing no more than 1 to 2 lbs per week because losing weight faster can have negative health consequences, such as muscle loss. It's never safe to reduce your calories by more than a few hundred per day without first consulting your doctor.