Hypoglycemia is not a disease, rather, it is a condition characterized by an abnormally low level of sugar (or glucose) in the blood. Since sugar is vital for the proper functioning of the body’s organs and systems, understanding and preventing hypoglycemia is extremely important. 60mg/dL (milligrams of glucose per deciliter of blood) to 120 mg/dL is generally accepted as the normal range for blood sugar. This level may vary depending on when a person has last eaten. A blood level of 50-60mg/dL is not uncommon for a person who has not eaten for a number of hours and does not necessarily indicate an abnormality. Hypoglycemia, a blood glucose level below 45 mg/dL, however, may signal a serious condition.
To understand hypoglycemia, one must first understand the normal metabolism of sugar in the human body. Glucose, or sugar, is the body’s main fuel and is acquired by the body in the form of carbohydrates (sugars and starches). Once ingested, carbohydrates are broken down into simple sugars, mostly glucose, in the intestines. These sugars are drawn from the intestines into the circulating bloodstream. From the bloodstream they enter the body’s cells where they are used to produce energy. Any unused glucose is stored in the liver as glycogen.
Under normal conditions, two hormones, insulin and glucagon control the amount of sugar in the blood. These are produced by the pancreas, a gland found in the upper abdomen. The pancreas is comprised of tissue that contain alpha and beta cells. When the level of sugar in the blood rises, the beta cells release insulin, which helps glucose enter the body’s cells. This action lowers the level of glucose in the bloodstream, keeping it within the normal range. When the level of glucose drops too low, the alpha cells secrete glucagon, signaling the liver to release it’s stores of glycogen and change them to glucose. This raises the level of blood sugar back to the normal range.