Blood sugar, or glucose, is the raw material your body uses to make energy. Metabolism is the rate at which your body converts, or metabolizes, that sugar into energy. The process of converting sugar to energy is known as the Krebs cycle. The Krebs cycle runs 24 hours a day, seven days a week because your body is in constant need of energy. The amount of sugar in your blood does not determine the rate of your metabolism, but it does determine how much energy you can produce.
Blood Sugar
You get blood sugar primarily from your diet. Your body breaks down all the food you eat into its basic components: fats, proteins and carbohydrates. The fats become fatty acids, proteins become amino acids and carbohydrates become glucose. Your body then absorbs these components through the intestinal wall and into the bloodstream. When the sugar enters your bloodstream, it triggers the pancreas to release insulin. The insulin puts the blood sugar inside all the cells in your body where it is converted to energy. Several other factors determine the rate at which you metabolize blood sugar including your age, level of activity and health status.
Age
As you enter your 40s, your metabolism slows as a result of muscle and bone loss, according to Gerard J. Totora, author of "The Principles of Anatomy and Physiology." Muscle and bone are both active tissues with constant energy demands and the more you have, the faster your body needs to metabolize sugar to meet those demands. The average individual loses approximately 10 percent of his muscle mass each decade after age 45, according to Weight Watchers. You can prevent this muscle loss by exercising regularly; the American Council on Exercises recommends at least 30 minutes of cardiovascular exercise most days a week and three days per week of resistance exercise.
Activity Levels
Each person's body has a basic metabolic requirement, or basal metabolic rate. This is the lowest rate at which you metabolize sugar to maintain all of your body's functions while doing the least amount of activity. Active individuals tend to metabolize sugar faster than their sedentary peers because movement increases the heart rate, breathing and other bodily functions. The more active you are, the more sugar you need to metabolize to support that activity.
Health Status
Certain illnesses affect the way your body metabolizes sugar. Diabetes prevents you from metabolizing sugar by keeping it from getting into your cells. With hypothyroidism, the sugar gets into the cells, but they are unable to convert it into usable energy. Because your body is not able to create energy efficiently, it will also slow your metabolism to conserve energy for vital functions. Viral and bacterial illnesses may increase your metabolism as your body raises your temperature and speeds up your immune system to fight the infection, according to "The Principles of Anatomy and Physiology."
References
- "Principles of Anatomy and Physiology"; Gerard J. Tortora et al.; 2010
- Weight Watchers: Aging and Metabolism
- MayoClinic.com; Hypothyroidism; June 12, 2010
- PubMed Health; Diabetes; May 10, 2010
