Insulin resistance may not be a term with which you are familiar, but it is important to know what it is and how it may affect you. Insulin resistance (IR) precedes Type 2 diabetes. It is asymptomatic, meaning there may not be any signs that it is happening. It is mainly caused by obesity, especially by something called “visceral fat.” Visceral fat surrounds the organs of the abdomen. It is the hardest fat to combat. Visceral fat causes a myriad of problems which will be discussed below.
More than 84 million people in the US over the age of 18 have prediabetes. There are approximately 329.5 million people in the United States, so that statistic means approximately 1 in 3 people have prediabetes.  Prediabetes means your blood glucose levels are elevated, but not to the degree to be diagnosed as diabetic.
The major contributing factor to the development of insulin resistance is poor lifestyle behavior, insufficient physical activity, and improper nutrition leading to being overweight or obese. Some people are genetically predisposed to have an increased risk for insulin resistance. For example, having a first-degree relative (parents and siblings) with diabetes or women with polycystic ovary disease. [1, 2]
RISK FACTORS INCLUDE
- Being overweight or obese
- Sedentary lifestyle
- Members of the BIPOC community (African American, Native American, Pacific Islander, Latinx, Native Alaskan)
- A history of diabetes during pregnancy
- A history of cardiovascular disease (including heart attack or stroke), high blood pressure, and elevated cholesterol. [3, 4]
WHAT IS THE PATHOPHYSIOLOGY (THE PHYSIOLOGIC PROCESS THAT LEADS TO THE DISEASE)?
- Insulin is the most well-known hormone in the body.
- It is made and secreted by the pancreas in response to elevated blood glucose levels (hyperglycemia = high blood sugar levels).
- Insulin moves glucose out of the blood and into the cells (liver, fat, and muscle) for storage.
- Cells can become insulin resistant if there is chronic stimulation of the pancreas, which causes an excessive release of insulin. Cells can gradually become less sensitive to insulin over time. This means the insulin becomes less effective at doing its job.
- Insulin resistance leads to more frequent elevations of blood sugar levels, followed by prediabetes and finally overt diabetes. This happens due to constant pressure on the pancreas and the eventual depletion of the insulin-producing cells within it. 
- Chronically elevated blood sugar can damage nerves and organs and lead to cardiovascular disease, chronic inflammation, kidney disease, eye disease (retinopathy and blindness), neuropathy, skin changes, high blood pressure, elevated lipids, and fatty liver disease. 
- Insulin resistance can also be found in the brain, which is called Insulin Resistance in the Brain. It can appear in the brain and not the rest of the body. In fact, this is an early sign of Alzheimer’s Disease. Alzheimer’s is often referred to as “Type 3 diabetes of the brain”. 
HERE ARE SOME DIABETES AND PREDIABETES STATISTICS ACCORDING TO THE CENTER FOR DISEASE CONTROL:
- 37.3 million people in the USA have diabetes (11.3% of the population).
- 28.7 million people have been diagnosed.
- 8.5 million people are undiagnosed (23.0% of adults). 
- 96 million people in the USA 18 years or older have prediabetes (38.0% of the adult population).
- 26.4 million people aged 65 years or older (48.8%) have prediabetes. 
WHAT CAN YOU DO ABOUT IT?
- Aerobic and resistance exercise is very important in combating IR. It helps the glucose move into the cells of the muscles. One small study that tested healthy individuals found that exercise can cause an immediate increase in insulin sensitivity which can last up to 48 hours. This can occur in healthy people as well as people with insulin resistance. The study concluded, “physical training can be considered to play an important, if not essential role in the treatment and prevention of insulin insensitivity”. 
- Inadequate sleep has been shown to affect insulin resistance. A small study examined 24-hr sleep deprivation in healthy individuals. It found that healthy people have decreased insulin sensitivity when they are sleep deprived. There are many studies that show evidence of the link between insufficient sleep quality and duration to an increased risk of obesity, insulin resistance, and type 2 diabetes. [10, 11, 12]
- Nutritional changes include eating more soluble fiber, vegetables, and fruits, and consuming less processed foods and added sugar. There are lots of hidden sugars in processed foods, sodas, and juices. You can also decrease the intake of high glycemic index carbs (including foods high in saturated and trans fats). They are the most important factor in increasing insulin blood levels.
- Obtain and maintain a healthy weight. Being overweight or obese leads to decreases in insulin sensitivity and increases the risk of type 2 diabetes.
- Visceral fat is especially important. It is that midsection weight gain we experience as we age. Visceral fat is “hormonally active fat,” meaning it secretes substances that cause or worsen inflammation throughout the body. This action (among others) increases the risk of insulin resistance, cardiovascular disease, hypertension, and cancers including breast, prostate, and colon. 
- Your sex hormones can help!
OTHER HIGHLIGHTS FROM VARIOUS STUDIES ARE REFERENCED BELOW:
- Menopausal hormone therapy reduced Alzheimer’s and neurodegenerative disease risk.
- Risk reduction was greater for formulations containing natural steroids (bioidentical hormone therapy).
- A longer duration of hormone therapy was associated with greater risk reduction.
- Risk reduction became apparent in women 65+.
- Precision medicine can be advanced by optimizing the type, route, and duration of therapy. [14, 15]
- MHT (menopausal hormone therapy) is associated with significantly decreased visceral abdominal fat and body mass index. Testosterone therapy does the same in men. [16, 17]
- Lifelong maintenance of physiologic hormone levels is necessary for good health and well-being. [16, 17]
- An estimate claimed there were 18,000 to 91,000 excess deaths in the United States in women aged 50 to 59 years from 2004 to 2009 because these women did not do MHT. Researchers proposed that these women suffered fatal metabolic consequences due to inadequate estrogen receptor function in the presence of low hormone levels. [18, 19]
- Sex hormones are anti-inflammatory for the body. They support the immune system and brain function. 
For more on hormone therapy, visit the link below.
- National Institute of Diabetes and Digestive and Kidney Diseases (2018). Insulin Resistance & Prediabetes. Accessed on October 15, 2022.
- Gambineri, A., & Pelusi, C. (2019). Sex hormones, obesity and type 2 diabetes: is there a link?. Endocrine connections, 8(1), R1-R9.
- Eckel, R. H., Alberti, K. G., Grundy, S. M., & Zimmet, P. Z. (2010). The metabolic syndrome. The lancet, 375(9710), 181-183.
- Myers, J., Kokkinos, P., & Nyelin, E. (2019). Physical activity, cardiorespiratory fitness, and the metabolic syndrome. Nutrients, 11(7), 1652.
- Konar, H. (2016). DC Dutta’s textbook of gynecology. JP Medical Ltd.
- Samuel, V. T., & Shulman, G. I. (2016). The pathogenesis of insulin resistance: integrating signaling pathways and substrate flux. The Journal of clinical investigation, 126(1), 12-22.
- Suzanne, M. (2014). Type 3 diabetes is sporadic Alzheimer׳ s disease: mini-review. European Neuropsychopharmacology, 24(12), 1954-1960.
- Centers for Disease Control and Prevention. (2022) National Diabetes Statistics Report. Accessed on October 16, 2022.
- Borghouts, L. B., & Keizer, H. A. (2000). Exercise and insulin sensitivity: a review. International journal of sports medicine, 21(01), 1-12.
- Koren, D., & Taveras, E. M. (2018). Association of sleep disturbances with obesity, insulin resistance and the metabolic syndrome. Metabolism, 84, 67-75.
- Reutrakul, S., & Van Cauter, E. (2018). Sleep influences on obesity, insulin resistance, and risk of type 2 diabetes. Metabolism, 84, 56-66.
- Gonzalez-Ortiz, M., Martinez-Abundis, E., Balcazar-Munoz, B. R., & Pascoe-Gonzalez, S. (2000). Effect of sleep deprivation on insulin sensitivity and cortisol concentration in healthy subjects. Diabetes, nutrition & metabolism, 13(2), 80-83.
- Shuster, A., Patlas, M., Pinthus, J. H., & Mourtzakis, M. (2012). The clinical importance of visceral adiposity: a critical review of methods for visceral adipose tissue analysis. The British journal of radiology, 85(1009), 1-10.
- Kim, Y. J., Soto, M., Branigan, G. L., Rodgers, K., & Brinton, R. D. (2021). Association between menopausal hormone therapy and risk of neurodegenerative diseases: Implications for precision hormone therapy. Alzheimer’s & Dementia: Translational Research & Clinical Interventions, 7(1), e12174.
- University of Arizona Health Sciences. (2021). A step toward advancing precision hormone therapies to reduce Alzheimer’s risk. ScienceDaily. Accessed on October 15, 2022.
- Papadakis, G. E., Hans, D., Rodriguez, E. G., Vollenweider, P., Waeber, G., Marques-Vidal, P., & Lamy, O. (2018). Menopausal hormone therapy is associated with reduced total and visceral adiposity: the OsteoLaus Cohort. The Journal of Clinical Endocrinology & Metabolism, 103(5), 1948-1957.
- Turner, R. J., & Kerber, I. J. (2017). A theory of eu-estrogenemia: a unifying concept. Menopause (New York, Ny), 24(9), 1086.
- Sarrel, P. M., Njike, V. Y., Vinante, V., & Katz, D. L. (2013). The mortality toll of estrogen avoidance: an analysis of excess deaths among hysterectomized women aged 50 to 59 years. American journal of public health, 103(9), 1583-1588..
- Turner, R. J., & Kerber, I. J. (2016). eu-estrogenemia, hormone therapy cessation, and early mortality. The Journal of Clinical Endocrinology & Metabolism, 101(4), L50-L51.
- Wilson-King, Genester. (2022). Dr. Wilson-King’s Hormone Guide. Victory Rejuvenation Center. Accessed on October 15, 2002.