What is glycemia?

Glycemia indicates the amount of glucose in the blood, this sugar is a vital energy source for our body. Glucose is a simple sugar found in certain foods, especially fruits, and a major source of energy present in the blood and animal body fluids. Glucose, when ingested or produced by the digestive hydrolysis of double sugars and starches, is absorbed into the blood from the intestines by a facilitated transport mechanism using carrier proteins. Excess glucose in circulation is normally polymerized within the liver and muscles as glycogen, which is hydrolyzed to glucose and liberated as needed. The determination of blood glucose levels is an important diagnostic test in diabetes and other disorders.

The levels of blood sugar in the body depend on glucose introduced by food, the hormonal regulation and the reserves stored in the body for later use. The equilibrium in the concentration of glucose in the blood is entrusted to two hormones in the body, the first being glucagon and the second insulin. The glycemic index is the measure of the rate at which ingested food causes the level of glucose in the blood to rise. The smaller the number of the glycemic index, the less impact the food has on your blood sugar. For example an index of 55 or less is low and good, 56 to 69 is medium, and 70 or above is high and unhealthy.

Why measure the level of glycemia?

This test verifies the levels of blood glucose and verify whether the conditions of hypoglycemia (low blood sugar) or hyperglycemia (high glucose levels in the blood) are present in the patient. Blood glucose may be important in diagnosing diabetes. Glycemic control in the body is achieved through several physiological mechanisms. An example of this is, when the blood sugar levels tend to drop to its lowest point in the morning, after a night of sleep and therefore hours of fasting. Or After a meal, glycemic levels increase as carbohydrates are broken down into simpler sugars such as glucose and absorbed from the intestine into the bloodstream. The glycemic level drops after a bout of severe exercise when the blood sugar is used as a source of energy for muscular activity. Glycaemia levels are also affected by the process of gluconeogenesis, where glucose is produced from non-carbohydrate sources such as glycerol, fatty acids and glucogenic amino acids. Extremely cold temperatures also cause much of the blood sugar to be used up, therefore lowering the blood glucose level.

Standard of preparation

Sampling is usually done in the morning in the hospital. There are no special preparations needed for this test. The doctor will advise and recommend if you need to be fasting prior to the blood examination. You should inform your doctor of any medication you are taking prior to the exam, as some medical treatments may interfere with the blood results.

Is the examination painful or dangerous?

The examination is neither painful nor dangerous. The patient may feel a tingling sensation with the entrance of the needle in the arm when blood is being extracted for examination.

How is the exam performed?

The exam consists of a simple blood sample test.