The body is constantly performing work, even during sleep. In order to carry out this work, whether through the muscle activity involved in exercise, or the work of breathing or the beating of the heart, energy must be supplied. A major starting point of fuel for cells is the six carbon sugar glucose, also known as dextrose. The body uses glucose to help form energy-containing compounds, and health conditions can be caused by high or low levels.
Blood Range
The body keeps blood glucose levels in a tight range. A large dose of glucose, generally from the oral intake of carbohydrates such as pasta, bread or sugars, will raise the level of glucose, and the bodies continued utilization of glucose will decrease the levels. The body works to keep the level of glucose in the range of about 60 to 100 mg/dL.
Regulation
The regulation of doses of glucose starts in the intestine. Special enzymes break down carbohydrates, and glucose transporters in the intestine take up the glucose. At the same time, the pancreas releases insulin, a protein hormone, into the blood stream. Insulin signals cells to take glucose out of the blood. Once in the cell, the glucose can be used for energy. If glucose levels fall, the liver and muscles will break down glycogen, which is the storage form of glucose, in order to keep the blood levels in the normal range.
Intake
The dosage of glucose can be administered by mouth or intravenously. By mouth, it can be in long chains called carbohydrates, or can be taken as pure glucose. Intravenously, it is mixed with a water-based carrier solution and administered straight into the blood. The concentration and amount administered depends on the body's needs. The intravenous route is the fastest. Lower blood sugar requires more glucose. An ongoing fast requires ongoing glucose. It is important that the dosage of medications and glucose be made by a qualified healthcare professional.
Conditions
Hypoglycemia is low blood sugar. It can be caused by prolonged fasting or an overdose of insulin given to treat diabetes. Slightly low levels can cause fatigue, weakness, headache, lightheaded, anxiety or irritability. It needs to be treated promptly because very low levels can lead to coma or death. On the other hand, extremely high levels of glucose, called hyperglycemia, can make the blood very viscous, like syrup, and damage the organs, also leading to adverse health outcomes. In addition, chronically elevated blood sugar that goes unnoticed will damage the blood vessels and organs. This condition is known as diabetes. It increases the risks of blood vessel disease, heart disease, strokes and kidney disease. The dosing of glucose is carefully controlled under these settings.
References
- "Lehninger Principles of Biochemistry"; David L. Nelson, et al.; 4th Ed 2004
- "Robbins and Cotran Pathologic Basis of Disease"; Vinay Kumar, et al.; 8th Ed 2009
