subject: What Is Basal Metabolism [print this page] Your body uses food as a furnace uses fuelYour body uses food as a furnace uses fuel. It burns the food to make energy. This produces heat, as any burning does. The more active you are, the more energy you need and the more heat you produce. When you are resting very quietly, you are producing the least amount of heat. Basal means "lowest," and metabolism means "change into energy." A basal metabolism test measures how much heat this is. This tells your doctor much about how healthy you are. The doctor usually measures your basal metabolism about nine o'clock in the morning. On the day before he does this, you must avoid active sports and work, and after about seven o'clock at night, you must not eat anything. After you have a good night's sleep, you must continue to be very quiet the next morning, and you are not allowed to eat any breakfast. Half an hour before the basal metabolism test begins, you lie quietly on a bed in the doctor's office. You relax, because there is nothing in the test that can possibly hurt you. When the doctor is ready, he or his nurse puts a soft rubber clamp on your nose so that you must breathe through your mouth. Then for about fifteen minutes you breathe through a wooden mouthpiece and a long tube into a big shiny can. The can is part of a calorimeter, a machine for measuring heat, that automatically makes certain tests on the air you breathe. From the record the testing machine makes of your breathing, and from your age and weight, the doctor can figure out your basal metabolism. The basal metabolism of each healthy person depends on his age and weight. When you were a baby and needed much energy just to grow, your basal metabolism was at its highest. As you grew older, it became less. When you reach your 'teens, your basal metabolism drops quite sharply. Then it will slowly decline as you grow older. Tall, thin people have a higher basal metabolism than short, fat ones. If your basal metabolism is too high or too low, it may mean that your glands are not working properly, and your doctor will give you the proper medicines and diet to correct this
