Blood glucose regulation is primarily controlled by two different hormones, insulin and glucagon. Secondary hormones such as epinephrine are also involved. Normally blood glucose is kept within a narrow range, approximately 70 to 100 mg per 100 ml of blood. If you have been diagnosed with an abnormal blood glucose reading, consult your physician for further guidance. A registered dietitian or certified diabetes educator can also help with meal plans to control your blood glucose.
Background
Under normal conditions, your blood glucose concentration is automatically kept within a narrow range, approximately 70 to 100 mg per 100 ml of blood. Blood glucose originates mainly from the carbohydrates in the foods you eat. After being digested and absorbed in the small intestine, small carbohydrate molecules, called glucose, travel to the liver. The liver then helps to control the amount of glucose entering the bloodstream.
Insulin
After a meal, the glucose content in the bloodstream can be high. In response to this, your pancreas secretes a hormone called insulin. Insulin helps lower blood glucose by signaling the liver to pick up excess glucose and convert it to a storage form called glycogen. Insulin also enables body cells to take up glucose directly from the bloodstream. The cells then metabolize glucose into useable energy for the body. Without insulin, glucose cannot enter body cells.
Glucagon
When you have gone for hours without eating, your blood glucose level starts to fall. This signals the release of another hormone called glucagon. Glucagon stimulates the liver to breakdown its stored glycogen into glucose, which is then slowly released into the bloodstream. This keeps your blood glucose level from falling dangerously low.
Epinephrine
If you experience a stressful situation, epinephrine, the "fight or flight" hormone, is released by the adrenal glands. Adrenaline, also known as epinephrine, signals the liver to breakdown glycogen into glucose and rapidly release it into the bloodstream. This surge of glucose enables you to have quick energy to deal with the stressful situation.
Implications
Thus, insulin, glucagon and epinephrine all work together to keep blood glucose levels regulated. When any one of these isn't working properly, your blood glucose can vary outside the normal range. Low blood glucose, or hypoglycemia, occurs when blood glucose falls below 40 to 50 mg per 100 ml of blood. Hyperglycemia, or high blood glucose, results when blood glucose exceeds 125 mg per 100 ml of blood.
References
- American Diabetes Association: Ask the Registered Dietitian
- World Health Organization: Diabetes
- American Dietetic Association: Diabetes and Diet
- American Diabetes Association: Carbohydrates
- "Understanding Nutrition"; Ellie Whitney and Sharon R. Rolfes; 2008
