Diseases Related to Insulin Resistance

Insulin resistance is at the root of many chronic medical conditions and it is completely avoidable. So consider adding avoiding insulin resistance to your health New Year resolutions. Insulin resistance affects every organ-system in the body.

What is Insulin Resistance?

Insulin is a hormone produced in the pancreas and released in response to meals. Its main purpose is to drive blood sugar into the cells so it can be used for energy and also directs fat metabolism. If blood sugar is chronically elevated it takes more insulin to clear sugar (glucose) from the blood and drive it into the cells. If blood sugar and insulin remain chronically elevated the cells eventually become resistant to it and it takes even more insulin to manage glucose levels.

In the presence of elevated insulin levels, it becomes difficult for the body to burn calories from energy stored in fat cells even during exercise. If insulin levels remain high long enough, fat becomes stored in the liver leading to fatty liver disease. See Why High Insulin Levels Are Dangerous.

Diseases Caused by Insulin Resistance

Let’s go through and list the medical conditions caused by insulin resistance by organ-system.

Brain:   Alzheimer’s disease

Heart:  Hypertension, atherosclerosis, and cardiomyopathy

Liver:   Fatty liver disease including steatohepatitis (inflammation of the liver) and cirrhosis

Kidneys:  Chronic kidney disease and glomerular hyperfiltration (diabetic nephropathy)

Muscles:  Sarcopenia and lipotoxicity

Reproductive System:  Polycystic ovary syndrome (PCOS), menstrual irregularities, infertility

Cancer:  Breast, uterine, cervical, colon, esophageal, pancreatic, kidney, and prostate cancers.

Metabolic:  Obesity and diabetes.

Comments on these Diseases

Alzheimer’s disease is now referred to as type 3 diabetes. A study published in Diabetes Care showed a chart showing the effects of insulin resistance on brain aging.  Those who were pre-diabetic had brains that looked a half year older than controls. Those with diabetes and HgA1C under 7.0 had brains that looked 1.7 years older, those with HgA1C between 7.0 and 9.0 had brains that looked 2.5 years older, and those with HgA1C greater than 9.0 had brains that looked 4.2 years older than controls.

High insulin is responsible for perhaps 75-80 percent of all obesity says Robert Lustig, MD in his book, Fat Chance.  Reduce insulin and you reduce obesity. Reduce obesity  you then reduce the risk of many chronic diseases.

Measuring Insulin Resistance

Insulin levels are easily measured in blood with a normal fasting range being 2 to 20 mIU/mL but we consider an optimal range being less than 5 mIU/mL  Fasting levels above 12 mIU/mL should raise concern of insulin resistance. Another simple method to determine insulin resistance is to use the TyG index which is a formula that uses fasting triglyceride and glucose levels. Here is an app you can use to calculated TyG. TyG is a logarithmic equation expressed at TyG = ln [Fasting triglyceride (mg / dl) x Fasting glucose (mg / dl)] / 2.

Reducing Insulin Resistance

You have nearly complete control in avoiding insulin resistance through lifestyle habits.

Insulin resistance can be reduced by any strategy to reduce insulin levels.  This includes eating low glycemic foods, practicing time restricted eating (intermittent fasting), exercise, and weight loss. Low glycemic foods are those that do not lead to a spike in insulin levels.  Time restricted eating gives the pancreas a break and enables insulin levels to drop to optimal levels reducing the risk of insulin tolerance. Exercise mimics insulin in that it stimulates a protein called GLUT-4 that facilitates the transport of sugar from the blood into the cells thus reducing the need for insulin. Also the more muscle you have, the more insulin receptors you have decreasing the need for the pancreas to produce insulin..