To Your Health
September, 2007 (Vol. 01, Issue 09)
Keep Your Body Energized
By understanding how the foods you eat affect how your body functions
By Peter W. Crownfield
Obesity is rapidly becoming a national epidemic. If you can't tell just by looking around, consider these ominous statistics from the Centers for Disease Control and Prevention (CDC). In 1995, no U.S. state had an obesity rate higher
than 20 percent, while a mere 10 years later, only four states had obesity rates lower
than 20 percent. In short, more Americans are getting fatter - a disturbing trend, to say the least, particularly when one considers the potential health consequences, such as diabetes, cardiovascular disease and some forms of cancer.
Are there secrets to avoiding obesity? Exercise certainly plays an important role; however, there's no doubt sound nutrition is the logical place to start. Diet plans are a proverbial dime a dozen, with limited success rates in the long term. Maintaining a safe weight begins not by jumping on the latest diet craze (and then the next one), but by understanding how the food you eat affects your body.
Food is composed of three basic nutrients: carbohydrate, protein and fat. The body needs all three in moderate amounts to function properly. For the purpose of this discussion, let's focus on carbohydrates and delve first into a concept many have heard about, but few have a complete understanding of: the glycemic index.
What Is the Glycemic Index?
The glycemic index (GI) is a ranking of carbohydrates based on their immediate effect on glucose (blood sugar) levels. Glucose is assigned a value of 100, while other carbohydrates are ranked relative to glucose. Essentially, carbohydrates that break down rapidly during the digestive process have the highest GI values. The blood glucose response is fast. On the other hand, carbohydrates that break down slowly and release glucose gradually into the bloodstream have low GI values.
The standard method of calculating the GI value of a particular food is to measure blood sugar while fasting (not eating for at least eight hours), and then two to three hours after consuming the food.
The Bigger Picture
Your body requires glucose for energy. When a food is being digested, enzymes in your stomach break down carbohydrates into glucose, which is then absorbed into your bloodstream. Your pancreas responds to the glucose surge by releasing insulin, which allows glucose to travel to the liver, where it is distributed to our body's cells for energy. Excess glucose is stored as glycogen and reconverted to glucose if blood sugar levels fall and more energy is required.