Insulin is a hormone which is made inside the body by an organ called the pancreas. It enables tissues throughout the body to take up glucose, or sugar, which is required to supply cells with energy. If a person becomes insulin resistant, cells no longer respond to insulin and, as glucose is not taken up, it remains in the blood, increasing the level of blood glucose. This resistance to insulin can occur in a disease known as type 2 diabetes, which is why insulin resistance and diabetes are connected. In type 2 diabetes, symptoms of thirst, hunger, increased urination and fatigue may occur, and treatment may involve changing diet and exercise habits or taking medication.
Normally, when the blood sugar level increases following a meal, the pancreas releases insulin into the blood stream. Insulin acts on cells and they are then able to take up glucose from the blood to use as energy. Some of the glucose may also be stored in a form known as glycogen, ready to be turned back into glucose if blood sugar levels fall when a person has not eaten for a while. In a person with insulin resistance and diabetes type 2, cells no longer respond to insulin when it is present at normal levels. This means that glucose remains in the blood instead of entering cells.
Type 2 diabetes tends to be associated with obesity, or being overweight. Higher amounts of body fat, together with lower levels of exercise, tend to increase the resistance of cells to insulin. People who have relatives with type 2 diabetes are at greater risk of developing the illness themselves. The condition is more common after the age of 40, although cases of insulin resistance and diabetes are being seen increasingly in younger people.
Diagnosis of type 2 diabetes involves measuring the level of blood glucose to see if it is too high. Sometimes the level will be slightly higher than normal, but too low to make a diagnosis of type 2 diabetes. This condition is known as pre-diabetes, where a person has a high risk of going on to develop type 2 diabetes unless treatment is started.
Treatment of insulin resistance and diabetes involves closely monitoring blood glucose levels. A combination of losing weight, eating healthily and exercising may effectively lower blood glucose for some people, but sometimes drugs or insulin injections may be needed as well. It is important to treat diabetes to prevent complications such as heart disease, stroke, kidney failure and damage to nerves, eyes and feet.
