Is insulin resistance the same as diabetes?

Posted on 9 November 2022

The short answer is yes and no. If left untreated, chronic insulin resistance can lead to prediabetes and then type 2 diabetes over time.

Dr Alkesh Magan, an endocrinologist at Mediclinic Sandton, explains that insulin is a naturally occurring hormone made by your pancreas that helps your body regulate blood sugar (glucose).


In effect, insulin acts as the “key” that opens the “doors” of the cells in your body. Once insulin opens these doors, glucose can move from your bloodstream into your cells to be used for energy. However, if your pancreas doesn’t work as it should, it may not make or release the insulin you need to control your blood sugars, which eventually results in diabetes.


Insulin resistance, which can be a precursor to prediabetes, occurs when cells in your muscles, fat, and liver start ignoring the signals from the insulin hormone to move glucose out of the bloodstream and into your cells.


“This means your body has to produce extra insulin to keep the sugar from the liver stable,” says Dr Magan. “The problem is that when you eat, you add calories to the body and the pancreas must ramp up the amount of insulin it produces even more. The pancreas has a finite lifespan and if you continuously use more insulin than you require, you damage the pancreatic tissue that produces insulin. The net result over a long period of time is that the pancreas wears out and production of insulin starts to drop.” When the pancreas can no longer keep up, blood sugar levels keep rising to the point of being in the diabetic range, which is damaging to the body.


Symptoms of severe insulin resistance include non-specific headaches, weight gain and heightened cravings for refined sugars and refined carbohydrates. So, who is more likely to develop this condition?


“People who have obesity as a co-morbidity are more likely to have problems,” says Dr Magan. “Those with a strong family history of type 2 are more genetically prone to develop insulin resistance, as are those with unusual hormonal problems, such as polycystic ovary syndrome (PCOS), that exacerbate insulin resistance. Individuals with certain conditions who’ve had cortisone injections for a long time are also at risk for insulin resistance, but its most commonly due to inactivity and obesity.”


Dr Magan adds that the relationship between insulin resistance and prediabetes is a spectrum of severity. “Individuals with insulin resistance have normal glucose and abnormally high insulin level in a fasting state; while in patients with prediabetes, blood sugar sits typically at 6.1 and 6.9 and they have a high or normal insulin level. Prediabetes is also defined by a glucose of between 7.8 and 11.1 after a glucose tolerance test. If insulin resistance isn’t actively treated it progresses to prediabetes.”


To determine whether you have an issue, your doctor may perform an oral glucose tolerance test (OGTT). This is a fasting blood sugar test, after which youre given a sugary drink. Blood tests then show how your body copes with the sugar load. The haemoglobin A1C (HbA1C) is another blood test that indicates average blood sugar levels for the past two to three months. Doctors often use this test to assess blood glucose control.


The good news is that patients with decent reserves in the pancreas (and who have normal glucose levels and high insulin levels) can increase their insulin sensitivity to a normal level by modifying their lifestyle, says Dr Magan. This includes meticulous avoidance of refined sugar and processed carbohydrates, adequate hydration and at least 150 minutes of exercise a week.

Published in Diabetes

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