When it comes to your metabolism, factors such as age and gender can work against you. Fad diets often promote "metabolism-boosting" foods like vinegar, cabbage, grapefruit and lemon juice. However, no special food or diet can raise the metabolism of a 60-year-old woman. Weight loss takes place when you cut your calories and become more physically active. The one thing that might slightly raise your metabolism is building more lean muscle through regular exercise.
Understanding Metabolism
Your metabolism dictates how many calories your body needs to function properly. Unfortunately, you have very little control over your metabolism. Your basal metabolic rate, or BMR -- the number of calories your body burns at rest -- is determined by more than one factor. Men typically have more lean muscle than fat and burn calories more quickly than women. However, as you grow older, you begin to lose muscle mass and gain body fat. Your BMR at age 20 may be significantly different than your BMR at age 60. Your BMR accounts for between 50 and 80 percent of calories burned. Thermogenesis, the energy your body uses to digest food, accounts for another 5 to 10 percent. You also burn calories through physical activity -- and this can vary greatly from one individual to the next, depending on if you lead a sedentary or active lifestyle.
Your Need for Calories
After age 20, your metabolism slows down by 1 to 2 percent for every decade of life. Thus, your need for calories decreases as well, says Mayo Clinic dietitian Katherine Zeratsky. For example, a 60-year-old woman who is 5 feet 5 inches tall may only need around 1,450 calories to maintain a healthy weight of 140 pounds if she leads a sedentary lifestyle. At age 30, she may need around 1,642 calories to sustain the same weight.
Myths About Metabolism
It can be helpful to get a ballpark estimate of how many calories you should be consuming. However, one of the misconceptions about your metabolism is that you can determine the exact number you need to lose weight or maintain your existing weight, according to St. John Providence Health System. The amount of physical activity you get from one day to the next is the deciding factor. Physical activity refers to any movement that burns calories, including doing housework, walking your dog, raking leaves or engaging in a form of exercise such as walking or water aerobics.
Strength training, or weight training, is a vital component of any exercise program and builds muscle mass. Lean muscle burns more calories than fat even when you're at rest, but only nominally; the American Council on Exercise indicates that if you gain between 3 to 5 pounds of muscle, you may burn an additional 15 to 30 calories a day. Regular physical activity also improves your overall health, states the National Council on Aging. Exercise and physical activity can be beneficial for people with diabetes, heart disease, arthritis and high blood pressure.
Metabolism and Your Weight
Losing weight ultimately depends on cutting calories and getting more physical activity. Mayo Clinic physician Dr. Donald Hensrud states that an abnormally slow metabolism is rarely the cause of weight gain. It's far more likely that you're simply consuming far more calories than your body needs. However, some medical conditions such as hyperthyroidism can make your metabolism flag. This condition is more likely to affect women over the age of 50. If you've trimmed calories and get regular exercise and still can't lose weight, talk to your physician.
References
- Better Health Channel; Metabolism Explained; July 2009
- Mayo Clinic; Metabolism: What's the Best Way to Boost It?; K. Zeratsky, R.D., L.D.; January 2010
- St. John Providence Health System: The Reality Behind Metabolism Myths
- American Council on Exercise: Daily Caloric Need Calculator
- Mayo Clinic; Slow Metabolism --Is It to Blame for Weight Gain?; D. Hensrud, M.D.; August 2009
- American Council on Exercise; One of the more common perceptions in some fitness circles ...; Dr. Cedric X. Bryant; March/April 2006
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