Hyperinsulinemia refers to an excess of insulin in the blood and is a condition often associated with type 2 diabetes. Hyperinsulinemia leads to problems regulating the amount of glucose circulating in the blood. This means that insulin-producing cells in the pancreas called the islets of Langerhans have to produce increasing amounts of insulin in order to maintain the blood glucose at a normal level. The pancreas continues to do this until eventually it can no longer produce enough insulin to meet the body’s needs, which leads to a rise in the blood sugar level.
Hyperinsulinemia can pose a number of risks, which include the following:
There are often no clear indicators of hyperinsulinemia, although the following symptoms may be present:
The earlier this condition is diagnosed, the more likely it is that the above problems can be prevented or the extent of them reduced.
As hyperinsulinemia is a feature of type 2 diabetes, the approaches to treatment are the same. Experts recommend reducing calorie intake as well as the intake of cholesterol, salt and alcohol. Other recommended lifestyle changes include reducing stress and increasing exercise. At least 30 to 60 minutes of moderate to vigorous exercise three times a week is advised to help individuals lose weight.
Even within just a few days of starting a calorie-restricted diet, insulin sensitivity can improve. A diet consisting of whole fresh foods that are high in fiber and have a low glycemic index are recommended. Examples include vegetables, fruits, wholegrains and beans. Carbohydrate intake should be moderately low, at around 45% to 65% of the total daily calorie intake. Saturated fats should be avoided and healthy monounsaturated and omega-3 fats should make up around 25% to 35% of daily calories. Good sources of monounsaturated fats include nuts, avocados and olive oil, and good examples of omega-3 fats are walnuts and fish. Saturated fats should be limited to less than 7% of the daily calories and trans-fatty acids to below 1%. Protein should make up 12% to 20% of the daily calorie intake, with legumes, fish and chicken being examples of good sources.
Exercise improves how receptive cells are to insulin (insulin sensitivity) and lowers the blood sugar and insulin level. To improve the blood sugar level, 150 minutes of moderate intensity cardiovascular exercise is recommended each week. The exercise should be carried out on at least three days, with no more than two days passing in-between.
Even losing a small amount of weight can improve insulin sensitivity. To maintain a healthy weight in the long term or to achieve a major weight loss, at least seven hours of moderate to vigorous cardiovascular exercise is recommended each week.
Long-term stress can increase the level of sugar and insulin in the blood and people suffering from stress on a regular basis should seek advice to learn ways of alleviating stress.
In cases where hyperinsulinemia is not responsive to lifestyle changes, medication may be prescribed to maintain a normal blood sugar level. Some of the drugs that may be prescribed are described below.
An example of an insulin secretion inhibiting agent is diazoxide, a thiazide drug that opens up the potassium adenosine triphosphate (ATP) channel in the beta cell membrane. This inhibits the release of insulin from the pancreas, as well as stimulating the release of glucose from the liver and catecholamine release, which raises the blood sugar level.
Dextrose or D-glucose is administered intravenously to rapidly elevate blood sugar levels. Glucagon is another substance that can be given intravenously or intramuscularly to raise the blood sugar level. Glucagon stimulates the release of glucose from the liver through hepatic glycogenolysis and gluconeogenesis.
In cases where patients are nonresponsive to these treatments, growth hormone and cortisol have been used to try and inhibit the effects of insulin, although success has been variable. Cortisol can reduce the hypoglycemic effects exerted by insulin and may also promote ketogenesis to provide an alternative source of energy. Hydrocortisone possesses glucocorticoid activity and stimulates gluconeogenesis and long-term use causes the pancreas to release glucagon, which then promotes glycogenolysis.