Glucose is the main source of energy that muscles and tissues use. When you eat, your primary nutrients come from proteins, fats and carbohydrates. The carbs get broken down in the stomach and converted to glucose, which is absorbed into the bloodstream, where it becomes blood glucose, or blood sugar. Many complications can arise from having blood glucose levels too high or too low.
Physiology
Blood glucose gets taken out of the bloodstream by insulin, which is secreted by the pancreas. Insulin transports the glucose to the body's cells to be converted into usable energy. According to the National Institutes of Health, or NIH, normal levels for blood glucose in a fasted state are 70 to 130 milligrams per deciliter, or mg/dl. The normal amount after meals is below 180 mg/dl. If too much or too little insulin is secreted, blood sugar levels become unstable.
Complications
If not enough insulin is secreted by the pancreas, the amount of glucose in the blood rises to dangerous levels, causing hyperglycemia, or high blood glucose. If too much insulin is secreted, then too much glucose is taken out of the blood, causing hypoglycemia, or low blood glucose. The American Diabetes Association says symptoms of hypoglycemia include confusion, weakness, shakiness, perspiration, and loss of consciousness. This condition can occur after skipping meals, getting more physical activity than normal or, if diabetic, injecting too much insulin following a meal.
Diabetes
Type 1, or insulin-deficient diabetes, is usually discovered in childhood and is characterized when insulin is not produced in the pancreas, causing increases in blood glucose. People with Type 1 diabetes usually have to perform routine insulin injections on themselves following meals to keep their blood glucose down. Those with Type 2, or insulin-resistant diabetes, are usually diagnosed in adulthood. This condition occurs when less insulin is secreted from the pancreas over time, and thus cannot remove enough glucose from the bloodstream.
Monitoring
Several methods can be used to self-monitor your own blood glucose. This is recommended to establish patterns of rises and falls in blood glucose, determine which foods spike your blood sugar and to see how physical activity can improve those numbers. The most common at-home method is with a finger-prick blood test. A drop of blood is placed on a strip, called a lancet, and put into a machine that reads glucose levels and presents the number on a digital display.
Control
If you notice your glucose rising out of the normal range, steps can be taken to improve your numbers. First, see a doctor to discuss diabetes and other conditions and talk about further lifestyle changes. The American Council of Exercise recommends regular exercise to help regulate blood sugar on a daily basis. Cut saturated fats out of your diet to lower blood triglycerides. If your blood sugar levels are too low, have a 15 g carbohydrate snack, then re-test in 15 minutes.
References
- Medline Plus: Blood Glucose Monitoring
- American Diabetes Association: Common Terms
- MayoClinic.com: Diabetes Definition
- MayoClinic.com: Use the rule of 15 to treat low blood glucose
- "Advanced Health and Fitness Specialist Manual"; American Council on Exercise; 2009
