Insulin Resistance: Causes And Metabolic Implications

Insulin is an anabolic hormone that plays key roles in glucose metabolism. Insulin resistance is a decreased biological response to normal concentration of circulating insulin. In insulin resistance, normal amounts of insulin are inadequate to produce a normal insulin response from fat, muscle and liver cells. Insulin resistance in fat cells results in hydrolysis of stored triglycerides, which elevates free fatty acids in the blood plasma. In muscles, it reduces glucose uptake, whereas in the liver, it reduces glucose storage with both effects serving to elevate blood glucose. High plasma levels of Insulin and glucose due to Insulin resistance often lead to metabolic syndrome and type 2 diabetes mellitus. The cause of the vast majority of cases of insulin resistance remains unknown. However, it is claimed that insulin resistance might be caused by a high carbohydrate diet. Studies have shown that glucosamine (often prescribed for joint problems) may cause Insulin resistance. It is also reported that insulin resistance occurrence in a population increased as sugar consumption and addition of high fructose corn syrup to diets increased. Physical inactivity and obesity have been implicated as factors, which aggravate insulin resistance. The presumption that a defect in specific gene may cause insulin resistance is still under investigation.