Glucose is one of the most well-known molecules due to its nature as an essential nutrient for human health. You ingest glucose in your food, and then your body uses blood to carry the glucose to the cells of every organ for the purpose of energy production. Although worries about obesity and diabetes have given glucose a bad name in recent years, all human life depends on maintaining adequate levels of this sugar.
Glucose is the most common of carbohydrates and an essential nutrient in the human body. This sugar is classified as a monosaccharide, as well as an aldose, a hexose and a reducing sugar. An alternative name for glucose is dextrose, a name which derives from the term dextrorotatory. This means that glucose is an optical isomer that shifts plane-polarized light to the right. Glucose's dextrorotatory status also classifies the carbohydrate as a D-isomer. A common name for glucose is blood sugar, although it can exist outside of the body as well.
Chemically, glucose is an organic molecule that consists of a carbon, hydrogen and oxygen chain. Each molecule has 6 carbon atoms, connected to 7 hydrogen ions, 1 oxygen ion and 5 hydroxide ions. While the chain form of this molecule is the simplest, glucose molecules more commonly form a ring structure called a cyclic chair form. Only 0.02 percent of glucose molecules in a water solution retain the simple chain molecular structure.
Although glucose is best known for its role in animal energy production, the sugar also exists in plant life. The chlorophyll in plants synthesizes glucose using carbon dioxide from the air and energy from the Sun's light. This synthesis creates starch which the plant can then store for future energy use.
All humans need a certain amount of glucose in their blood to maintain energy and proper organ function. For a healthy adult, the typical concentration of glucose in the blood is between 65 and 110 mg/mL, or milligrams per milliliter of blood. People with diabetes often have higher levels of blood glucose, due to decreased insulin to remove the sugar. In such cases, levels between 70 and 130 mg/mL are common prior to eating, while glucose levels may rise above 180 mg/mL after a meal.
In health, one of the most important aspects of glucose is its influence on such diseases as diabetes. If you have diabetes, the best method for controlling the disease is by monitoring your blood glucose level. This level will show, over time, the amount of sugar in your blood. To test a blood glucose level, use a lancet to obtain a drop of blood from your fingertip. Press the blood drop to a glucose testing meter and wait for the strip to show your result. Record this level for future reference. It is also possible to check urine for glucose levels, but this test is much less accurate.