In the presence of insulin resistance, the hormone insulin, which is produced by the organism itself, can have little or no regulatory influence on body cells. Especially cells of show a reduced responsiveness to the proteohormone in case of insulin resistance.
- Musculature
- Fatty tissue or
- Liver
In general, insulin resistance does not only affect the body’s own insulin.
Even externally substituted insulin preparations can hardly have any effect. Insulin resistance was defined as a condition in which the beta cells of the pancreas would have to produce and excrete approximately 200 I.U. per day to maintain the regulatory functions of the hormone.
However, these quantities could not be synthesized even by a healthy pancreas. As a result, the affected persons have an elevated blood sugar level (blood glucose level). The occurrence of insulin resistance is primarily typical for type 2 diabetes mellitus.
Insulin resistance can also be detected in some preliminary stages of this disease, which increases over the course of the disease and gradually reduces the responsiveness of the insulin receptors. So far, it has not yet been possible to conclusively prove which mechanisms are responsible for insulin resistance. 1. overweightAlthough both diabetes type 2 and its precursors are closely related to obesity (overweight), slim people can also develop this type of diabetes.
Nevertheless, overweight is probably the most important risk factor in connection with the development of insulin resistance. 2. hereditary dispositionIn addition, it has been assumed for some time that hereditary components are also involved in the development of insulin resistance. It has been proven that children with one parent suffering from type 2 diabetes have a 50% risk of becoming diabetic themselves.
In those cases where both parents are affected, this probability rises to 80%. 3. nutrition/exerciseA further cause for the development of insulin resistance is the disproportion between carbohydrate (or calorie) intake and physical activity. Too many calories and too little exercise increase the amount of free fatty acids in the blood.
This in turn reduces the utilization of sugar in muscle and fat cells. In the long term, this results in a reduction in the responsiveness of muscle and fat cells to insulin (insulin resistance). The organism then stimulates the B cells of the pancreas, resulting in increased insulin secretion.
The increased insulin supply then provokes a downregulation of the insulin receptors on the cells, and insulin resistance increases steadily. 4 DrugsThe development of insulin resistance can also be attributed to the intake of various drugs. In particular, the use of cortisol, the antagonist of insulin, can lead to a reduction in insulin action.
Since an increased release of cortisol occurs in various infectious diseases, infections are also considered a possible cause of insulin resistance. Other reasons for the occurrence of insulin resistance:
- Metabolic disorders with high fat content in the blood
- Diseases that lead to an increase in the production of contrainsulinic hormones (for example: acromegaly)
- Polycystic ovarian syndrome (PCOS)
- Long lasting malnutrition
Many people affected by insulin resistance have an increased body weight. Abdominal fat plays a particularly important role here.
The abdominal girth can be determined as a measure of the amount of abdominal fat. The so-called body mass index (short: BMI) is also often used to determine the nutritional status. In addition, if insulin resistance is suspected, the amount of triglycerides (blood fats) dissolved in the blood should be determined.
Values higher than 2.44 mmol/liter (215 mg/dl) should be followed up urgently by further diagnostics. Furthermore, a reduced production of the hormone adiponectin, which is produced by fat cells, is an important indication of insulin resistance. Further resistance tests are the so-called sugar stress test (oral glucose tolerance test, or oGTT for short) and the measurement of fasting insulin levels.
A suitable and comprehensive therapy for insulin resistance consists of several components.In classic type 2 diabetics, a calorie-reduced diet (so-called hypocaloric diet) should be followed. This means that the daily calorie intake in women should not exceed 1400 kilocalories. Male type 2 diabetics may consume approximately 1800 kilocalories per day.
In addition to following a diet, increasing the physical activity of affected patients plays a major role in insulin resistance therapy. Furthermore, the temporary increase of insulin intake to very high doses in short intervals is considered a possibility to break through insulin resistance. Insulin administration can be subcutaneous (under the skin) or intravenous (into the vein).
For this form of insulin resistance therapy, normal and/or analogue insulins are suitable preparations. It has been proven that after the initially high doses, a reduction in the amount of insulin applied is possible after only a few days. Furthermore, there are various drugs that are used specifically for the treatment of insulin resistance.
Among the best known drugs are All of these drugs belong to the group of so-called oral antidiabetics. One of the most important side effects is the risk of developing hypoglycemia, which makes regular blood sugar control necessary while taking most oral antidiabetics. It is precisely this fact that is the great advantage of metformin, which is probably the most commonly used.
Because of its mechanism of action, metformin does not carry the risk of hypoglycemia and thus causes metabolic disorders much less frequently.
- The biguanide metformin
- The alpha-glucosidase inhibitor acarbose or
- The insulin sensitizer Pioglitazone.
Insulin resistance usually develops over a long period of time and depends on genetic factors, diet and physical activity. Too many calories and too little physical activity lead to an ever-increasing insulin resistance over time, so that the chances of a cure are reduced.
With an incipient insulin resistance, on the other hand, insulin sensitivity can often be increased again through a conscious and healthy diet and physical activity, so that there is a chance of a cure through these measures. The taking of tablets or even the injection of insulin can thus be avoided in many cases. The lifestyle change measures mentioned above are in any case useful to counteract at least a further advance of insulin resistance.
In the development of insulin resistance, a vicious circle of a diet too rich in calories and insufficient exercise plays an important role. A disproportion between the calories ingested and the energy consumption of the body leads to an increase in blood fat and blood sugar levels. The body tries to counteract this by an increased release of insulin.
This in turn results in an increased storage of excess calories in the fat cells. As a result, the human body continues to gain weight, which also limits physical activity and performance. For overweight people with insulin resistance it is therefore particularly important to lose weight.
This can often break the vicious circle. The blood sugar and blood fat levels drop. In addition, insulin sensitivity rises again.
However, the pathological changes in insulin resistance are only reversible to a certain extent. At least, weight loss can counteract an increase in insulin resistance. Insulin resistance is an essential component in the development of polycystic ovarian syndrome (PCO).
This disease is a metabolic disorder in women which, in addition to insulin resistance and obesity, is often accompanied by masculinization due to an excess of male sex hormones. The absence of ovulation and cysts in the ovaries can also be part of the disease. It has not yet been possible to determine with certainty the exact relationship between insulin resistance and other possible symptoms of PCO.
However, affected women have an increased risk of developing diabetes or cardiovascular disease. For women with PCO and overweight, weight reduction should be primarily aimed at through healthy nutrition and sufficient physical activity.These measures can often lead to an improvement in the symptoms, including insulin resistance. If the symptoms of PCOs cannot be alleviated by natural measures, often only hormone treatment remains as a therapeutic option.
Insulin resistance must often also be treated with medication in the case of increased sugar levels. An overview of all topics of internal medicine can be found under Internal Medicine A-Z.
- Diabetes mellitus
- Blood sugar
- Sugar stress test – That’s what it’s for!