Your metabolism controls the rate your body burns calories at rest -- all the chemical functions that keep your body functioning take energy, and calories are energy. Your body needs a minimum number of calories to maintain itself. When you don't meet that minimum, your metabolism slows down to conserve energy, burning fewer calories. If you're trying to lose weight, a slower metabolism can stall your progress.
Understanding Your Metabolism
According to the Harvard Medical School, most people need between 1,200 and 1,500 calories to maintain metabolic function. Your metabolism is made up of three components: your basal metabolic rate, or BMR, which is how many calories you burn at rest, calories you use for your physical activity and digestion, also known as the thermic effect of food. Digesting protein uses more calories than digesting either carbohydrates or fats. Although your metabolism is controlled by hormones and your nervous system, you can raise your metabolism in several ways. Muscle burns more calories at rest than fat, so increasing muscle mass will raise your BMR. Exercising more will increase the energy you use for physical activity and you can increase thermogenics by eating more protein and spicy foods.
Calories and Metabolism
If you restrict calories too much, your metabolism can slow by as much as 15 percent. You need at least 1,200 calories to keep you metabolism functioning. If your metabolism is already slowed due to extreme dieting, it can recover -- but it will take time. Eat enough food and eat on a regular schedule. Your body slows metabolism because it thinks you're starving and there isn't enough food. You need to teach your body that more calories are coming on a regular basis so that your metabolism shuts off the starvation mode and starts burning calories at its regular rate.
Raising Your Metabolism
Exercise, specifically strength training will increase the number of calories you burn. Building muscle will raise your BMR, and you'll burn more calories at rest. Make sure to get plenty of rest -- a lack of sleep can slow your metabolism. Never skip meals and try to eat every two to three hours. Increase your fiber intake -- fiber is indigestible, but your body uses energy trying to break it down anyway -- raising your metabolism. Fiber also adds bulk without adding a lot of calories and can promote weight loss.
Counting Calories
Determining the number of calories you need to eat can be tricky. Cutting calories will speed up weight loss -- but only to a certain point. If you cut calories too much, weight loss stalls because of your slowed metabolism. It takes about 15 calories per pound of body weight to maintain your current weight. To lose weight, you need to eat less, creating a calorie deficit. For example, if you're moderately active and weigh 150 lbs., you need 2,250 calories to maintain your current weight. It takes a 3,500-calorie deficit to lose 1 lb. So subtracting 500 calories daily and eating 1,750 calories should result in losing 1 lb. each week. But if you subtract 1,000 calories daily in an effort to speed weight loss, at 1,250 calories you may be in danger of slowing your metabolism.
References
- Harvard Medical School Health Beat; Calorie Counting Made Easy; April 2009
- Better Health Channel: Metabolism Explained
- Mayo Clinic; Metabolism and Weight Loss -- How You Burn Calories; October 2009
- American College of Sports Medicine; Metabolism Is Modifiable with the Right Lifestyle Chocies; March 2009
Member Comments