What is Insulin Resistance?


Insulin Resistance, also known as Metabolic Syndrome, is a condition in which chronically high levels of blood sugar and insulin have caused the body’s mechanism for regulating insulin and blood glucose (sugar) to fail. Because there is so much insulin circulating in the body, the cells become less responsive to it.

How does insulin become chronically high? When we eat, our body breaks down the carbohydrates in our food into glucose. Insulin, the hormone which helps the body store glucose, is secreted in response to any meal which contains carbohydrates or excess protein. The more carbohydrate one eats, the more insulin will be secreted. And the more insulin in the blood, the less likely that the body will be able to burn any fat stored for fuel. Insulin keeps fat locked in the fat cells when carbohydrates (glucose) are available for fuel instead.

If a person eats large amounts of carbohydrates on a daily basis (as Americans have been doing since the USDA published the Food Pyramid), blood sugar and insulin levels become high and never return to a normal to low baseline.

Over time, the cells of the body become resistant or "numb" to the high amount of insulin which is always circulating. More and more insulin is required to push blood glucose into the cells, and more and more fat gets permanently locked into the fat cells.

As the condition of resistance progresses, pre diabetes symptoms develop, and eventually if left untreated, the pancreas becomes damaged and is unable to produce enough insulin to counteract the high level of blood sugar. The blood sugar levels then climb very high, and the person is diagnosed with Type 2 diabetes at that point.

So the process of developing type 2 diabetes can be recognized as a linear one over time:

  1. Insulin sensitivity is damaged first: Over time, a high carb diet causes the cells of the liver and muscles to become resistant to insulin's message to store sugar. This is especially true of refined carbs such as sugar and white flour. A lack of exercise can also have an effect because high intensity exercise can have the effect of making muscles more insulin sensitive. This may explain why athletes can handle a higher carb diet.
  2. Pre diabetes then develops: This resistance to insulin worsens over more time until pre diabetic symptoms develop and blood sugar and insulin are chronically high.
  3. Pre diabetes finally worsens into diabetes: If left untreated, the pre diabetes worsens, more and more insulin is needed to control blood sugar, the pancreatic ability to function becomes damaged, and eventually full blown diabetes develops.

Over the past 45 years or so, as Americans have been advise to follow a low fat, high carb diet, more people are suffering from chronically high blood sugar and insulin levels. In turn, the number of people diagnosed with diabetes has increased dramatically in the US, and indeed all over the world, as other countries adopt the standard low fat, high carb American diet.

Insulin resistance is associated with other health problems, such as high cholesterol, high blood triglycerides, high blood pressure and coronary heart disease. The combination of these conditions is called Metabolic Syndrome. In my mind, Metabolic Syndrome is really just a label for the symptoms of severe insulin resistance, and treatment should start there.

Check out my advice on how to reverse insulin resistance symptoms and avoid a worsening of insulin sensitivity in the future.


Resources for Further Reading



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