Glucose enters the bloodstream by absorption from the small intestine. It is carried via the portal vein to the liver, where part is stored as glycogen, the remainder reentering the circulatory system. Another site of glycogen storage is muscle tissue. Glucose is an important source of fuel for the body, especially for the brain and for red blood cells, which use no other fuel. Glucose is stored in the body in the form of glycogen in body cells, especially in the liver and muscle, and is metabolized in tissues to generate the adenosine triphoshate (ATP) which provides energy.
According to the American Dental Association (ADA), people with diabetes are more prone to periodontitis, tooth decay, oral fungal infections, taste diminishment, gingivitis and delayed healing time than people without the disease.
When glucose levels fall to hypoglycemic levels, cells cannot function normally, and symptoms develop such as nervousness, cool skin, headache, confusion, convulsions or coma. Ingested glucose is absorbed directly into the blood from the intestine and results in a rapid increase in the blood glucose level. Studies have found that glucose is the quickest form of sugar to be absorbed by the body to combat hypoglycemia. Glucose tablets and gels are only for mild and moderate cases of hypoglycemia. According to the ADA, 10 to 15 grams of glucose is effective to treat mild hypoglycemia while a more moderate reaction will require an additional 10 to 15 grams.
Candy, cake frosting, and honey are good ways to help fight low blood sugar. However, they contain sucrose, or white sugar, which takes a while to digest in the stomach. This could take minutes to properly digest, minutes in which you might not want to waste when suffering from low blood sugar. In addition, it is important not to give glucose gel to anyone who is unconscious and unable to swallow. In the case of severe hypoglycemia call an ambulance or administer glucagon if available.
Although fructose ALONE has no advantages to glucose ALONE, there was a single study that suggested it was of some benefit when used in combination with fructose in a sports drink. Adopo E et al (Appl Physiol 1994 Mar;76(3):1014-9) studied the effects of a combination 50 gram fructose/50 gram glucose drink compared to a pure 100 gram glucose supplement. The cumulative amount of exogenous carbohydrate metabolized in the combined carbohydrate drink was 21% greater than that observed when 100g of pure glucose alone was ingested. They speculated that this might be related to differing routes for absorption and metabolism of exogenous glucose and fructose, resulting in less competition for oxidation when a mixture of these two hexoses is ingested than when an isocaloric amount of glucose alone was ingested. They concluded that, from a practical point of view, these data may provide experimental support for using mixtures of carbohydrates in the energy supplements for endurance athletes.