Insulin Resistance

Insulin is a pancreatic hormone that allows the body to lower blood sugar levels (glucose) after eating. People with insulin resistance usually produce more insulin to offset their body’s insufficient response.

Overview

Insulin resistance, or low insulin sensitivity, happens when cells throughout the body don’t respond properly to the hormone insulin, especially cells in:

  • Muscles

  • Fat 

  • The liver

Insulin is a pancreatic hormone that allows the body to lower blood sugar levels (glucose) after eating. People with insulin resistance usually produce more insulin to offset their body’s insufficient response.

Eventually, the body may not produce enough insulin to keep blood sugar in a normal range. Slightly elevated levels are classified as prediabetes, a precursor to type 2 diabetes.

Patients with insulin resistance or prediabetes can often prevent developing type 2 diabetes by making lifestyle changes such as:

  • Increasing physical activity

  • Eating a balanced diet low in sugar

  • Losing weight and abdominal fat

Our comprehensive guide covers everything you need to know about insulin resistance, including what causes it, potential complications, and how to treat it.

What Is Insulin Resistance?

Insulin resistance is when your tissues no longer adequately respond to insulin to lower blood glucose levels. Glucose is the sugar molecule your body uses for energy.

Insulin is produced by beta cells in the pancreas. Blood sugar increases shortly after eating as your body breaks down sugars and starches and they’re absorbed by your gastrointestinal tract and enter your bloodstream.

Insulin lowers blood sugar levels by telling the body to move sugar into tissues throughout the body. If you’re physically inactive, insulin primarily shuttles blood sugar into fat cells or your liver for energy storage.

Insulin resistance often develops over time and can go unnoticed until blood glucose levels are chronically elevated. A combination of genetics and lifestyle habits increases a person’s risk of developing insulin resistance.

Insulin resistance without treatment with lifestyle changes or medications may lead to conditions such as:

Improving your diet and exercise habits can also improve your insulin sensitivity. Also, some causes of insulin resistance, like pregnancy, are temporary.

Symptoms

Many people with insulin resistance don’t have symptoms until the condition progresses.

Symptoms of Insulin Resistance

Insulin resistance often isn’t detectable without expensive lab equipment. Healthcare providers will typically find out a patient has insulin resistance after their condition progresses to prediabetes or type 2 diabetes.

There are some signs of insulin resistance, though, which we’ll cover below.

Prediabetes Symptoms

Like insulin resistance, prediabetes often doesn’t cause any noticeable symptoms. But some people develop prediabetes symptoms such as:

  • Acanthosis nigricans. These are characterized by dark patches within skin folds in locations like the neck, armpits, or groin.

  • Skin tags. These small and soft growths often develop on the neck or underarms.

  • High blood sugar levels. Medical professionals can diagnose high blood sugar with a blood test. Some of the symptoms can include fatigue, frequent urination, and increased thirst.

Diabetes Symptoms

Symptoms of diabetes tend to get worse the more the condition progresses without treatment. Some of the signs and symptoms include:

  • Frequent urination

  • Persistent thirst

  • Feeling very tired

  • Itching around the genitals

  • Repeatedly getting thrush infections

  • Slow wound healing

Chronically high blood sugar levels in patients with advanced diabetes can lead to nerve and blood vessel damage. It could also cause diabetic retinopathy or peripheral neuropathy.

Diabetic Retinopathy Symptoms

People with diabetic retinopathy can develop bleeding in the gel-like fluid inside of their eyes. This can cause symptoms such as blurry vision, floaters in your vision, or even blindness.

Diabetic Peripheral Neuropathy Symptoms

Diabetic peripheral neuropathy is a group of conditions characterized by damage to nerves in the limbs, particularly the legs and feet. It can lead to symptoms such as:

  • Numbness

  • Tingling

  • Burning

  • Weakness in the limbs

  • Unusual pain

  • Increased pain sensitivity

If you notice any of these symptoms, seek medical attention.

Insulin Resistance Symptoms in Females

Women with type 2 diabetes may develop irregular menstrual cycles. Many people assigned female at birth who have type 2 diabetes also have polycystic ovary syndrome (PCOS).

PCOS affects about eight to 13 percent of reproductive-age females. Possible signs and symptoms include:

  • Irregular menstrual cycles

  • Infertility

  • Excessive hair on the face or body

  • Acne or oily skin

  • Hair loss

  • Weight gain, especially around the abdomen

We’ll explore the potential causes of insulin resistance below.

Treatments for Weight Loss

Learn about weight loss

Causes

Insulin resistance can develop due to a combination of lifestyle factors like diet and exercise habits, as well as genetics. Some underlying conditions can also cause insulin resistance.

What Causes Insulin Resistance?

The development of insulin resistance can be attributed to various factors, including:

  • Obesity. Experts believe excess body fat, especially excess visceral fat around the internal organs, is the main cause of insulin resistance.

  • Physical inactivity. A sedentary lifestyle can contribute to excess body weight. But regular physical activity may help prevent diabetes.

  • Family history. People with a family history of diabetes or prediabetes are at an increased risk of developing it too. According to the American Diabetes Association, several genes have been discovered that increase a person’s risk of insulin resistance.

  • Genetic conditions. A number of genetic conditions have been linked to the development of insulin resistance, including myotonic dystrophy, ataxia-telangiectasia, Alstrom syndrome, Rabson-Mendenhall syndrome, Werner syndrome, lipodystrophy, and PCOS.

  • Poor diet. Diets high in processed foods, refined carbohydrates, and sugars can contribute to insulin resistance and associated risk factors like obesity.

  • Hormonal imbalances. Conditions that cause hormonal imbalances can also increase your risk of insulin resistance. Some of these include PCOS, Cushing’s syndrome, and pregnancy, which can lead to gestational diabetes.

Risk Factors

Most cases of insulin resistance are linked to lifestyle habits and other health conditions. These are known as risk factors.

Risk Factors for Insulin Resistance

Prediabetes affects roughly 84 million adults in the United States. This works out to be about one in three people.

Several risk factors increase the likelihood of developing insulin resistance or diabetes, such as:

  • Excess body weight, especially around the waistline

  • Having overweight or obesity

  • Being over 45 years old

  • High blood pressure (hypertension)

  • Elevated blood lipids, including high triglyceride levels, low HDL (high-density lipoprotein) cholesterol, and high (low-density lipoprotein) LDL cholesterol levels

  • A sedentary lifestyle or being physically active less than three times a week

  • African, Asian American, Native American, or Pacific Islander ancestry

  • Having certain health conditions like PCOS or metabolic syndrome

  • Non-alcoholic fatty liver disease

  • History of heart disease or stroke

  • Previously having gestational diabetes

  • Having given birth to a baby over nine pounds

  • Taking certain medications such as glucocorticoids, antipsychotics, and some medicines for HIV

  • Sleep apnea

If you have any of the risk factors for insulin resistance and think you may have the condition, see a healthcare provider for a potential diagnosis.

Diagnosing

The main way healthcare professionals diagnose insulin resistance is with blood tests, but they’ll start with other assessments.

Diagnosing Insulin Resistance

Medical providers will consider many factors when determining if you may be at risk for insulin resistance. Initial tests and assessments usually include a:

  • Review of your family medical history and whether you have a family history of diabetes

  • Physical exam to look for signs of advanced diabetes, such as poor circulation or eye problems

  • Review of your personal medical history and whether you have any risk factors like a high body weight for your height (calculated with BMI, or body mass index)

  • Review of your symptoms, if you have any

If they suspect you may have insulin resistance, your healthcare provider will likely want to order a blood test.

Blood Tests for Insulin Resistance

Directly testing for insulin resistance is difficult and usually reserved for laboratories used for research.

Healthcare professionals often look for prediabetes by running a test, either a fasting plasma glucose test or A1C test. Less commonly, you might get an oral glucose tolerance test.

Fasting Plasma Glucose Test

During a fasting plasma glucose test, you’ll avoid eating for at least eight hours until you have a blood sample taken. This blood sample will be measured to see if your blood sugar levels are elevated.

A1C Test

The A1C test goes by several other names, including:

  • HbA1c test

  • Glycated hemoglobin test

  • Glycohemoglobin test

It provides information about your blood sugar levels over the past three months. You don’t need to fast for this blood test. It examines your blood sugar levels by looking at the amount of blood sugar attached to hemoglobin molecules in your blood.

Glucose Tolerance Test

Less often, healthcare providers administer an oral glucose tolerance test. This one measures blood sugar after fasting and again two hours after you drink a sugary drink.

The fasting plasma glucose and oral glucose tolerance tests are more sensitive than the A1C test. These tests might pick up prediabetes that may be missed by the A1C test.

Who Should Be Tested for Insulin Resistance and Diabetes?

The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) recommends testing for diabetes in people:

  • Who have overweight or obesity and one or more other risk factors for diabetes

  • With a sibling, parent, or children with type 2 diabetes

  • Without risk factors starting from age 45

If your results are normal but you have other risk factors for diabetes, it’s a good idea to get retested at least every three years.

Treatment

Making lifestyle changes can help reverse insulin resistance before it progresses to diabetes or prediabetes. Medications can also help control blood sugar levels.

How to Fix Insulin Resistance

Insulin resistance treatment often involves lifestyle modifications or medications.

Lifestyle Changes

Lifestyle changes you can make to help improve your insulin levels might include dietary changes, regular physical activity, and weight loss.

Dietary Changes

Eating a balanced diet full of whole grains, lean proteins, and healthy fats can improve insulin sensitivity. Your healthcare provider might recommend eating:

  • Plenty of vegetables, fruit, beans, lentils, and nuts

  • Complex carbohydrates like brown rice or quinoa

  • Extra-virgin olive oil

  • Fish, especially fatty fish

  • A moderate amount of dairy

  • Little to no red meat

  • Little to no sweets or sugary drinks

Research consistently suggests that the Mediterranean diet (which includes these food pillars) is beneficial for people with prediabetes or diabetes. 

Regular Physical Activity

Exercise can potentially help you lose weight and fat around your abdomen. It may also improve insulin sensitivity by changing the way your body uses insulin.

The American Diabetes Association recommends aiming for 150 minutes or more minutes of moderate exercise a week. This could be:

  • Brisk walking

  • Doubles tennis

  • Water aerobics

  • Cycling

  • Dancing

  • Pushing a lawn mower

Try a few things to see what you enjoy.

Weight Loss

Reducing your body weight can significantly improve insulin sensitivity if you have overweight or obesity.

Making dietary changes and moving your body more can both support weight loss. But it’s a myth that you can lose weight in a particular area by exercising that part of your body. For example, performing crunches doesn’t help you lose fat specifically from your abdomen.

Diabetes Care Medications

No medication can cure insulin resistance, but some medications might help treat other health problems that often occur with insulin resistance. For instance, many patients take medications for high blood pressure or high cholesterol.

Many medications can help people at risk of diabetes manage their blood sugar. The first-line medication healthcare providers prescribe is often metformin.

Other medications prescribed to help treat type 2 diabetes include:

  • GLP-1 receptor agonists such as semaglutide

  • Insulin

  • Alpha-glucosidase inhibitors

  • Biguanides

  • Dopamine-2 agonists

  • Dipeptidyl peptidase-4 (DPP-4) inhibitors

  • Meglitinides

  • Sodium-glucose transport protein 2 (SGLT2) inhibitors

If you’re interested in compounded semaglutide for weight loss, see if you qualify on our women’s telehealth platform.

Rx Available

Weight loss treatment that puts you first

Prevention

Insulin resistance can often be prevented through lifestyle changes like exercising more and making better food choices.

Insulin Resistance Prevention Tips

Healthy lifestyle choices can help reduce your odds of developing insulin resistance or type 2 diabetes. They may be especially beneficial for folks with a family history of type 2 diabetes. 

In terms of how to reverse insulin resistance, lifestyle changes you can make include:

  • Maintaining a healthy weight

  • Staying physically active with things like walking, cycling, strength training, skating, rock climbing, and running

  • Eating a balanced diet low in sugar and high in nutrient-dense foods, such as fruits, vegetables, whole grains, and lean protein

  • Quitting smoking or avoiding smoking if you don’t currently smoke

  • Receiving regular health screenings to monitor blood sugar levels, lipid levels, and blood pressure

If you think you may have insulin resistance syndrome and want to explore your treatment options, get in touch with a healthcare provider.

This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment. Learn more about our editorial standards here.


16 Sources

  1. Alrashed FA, et al. (2023). Investigating the relationship between lifestyle factors, family history, and diabetes mellitus in non-diabetic visitors to primary care centers. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10472303/
  2. American Diabetes Association. (n.d.). Oral & injectable medications for type 2 diabetes. https://diabetes.org/health-wellness/medication/oral-other-injectable-diabetes-medications
  3. American Diabetes Association. (n.d.). Weekly exercise targets. https://diabetes.org/health-wellness/fitness/weekly-exercise-targets
  4. American Diabetes Association. (n.d.). What is insulin resistance?. https://diabetes.org/health-wellness/insulin-resistance
  5. American Diabetes Association Professional Practice Committee. (2023). Prevention or Delay of Diabetes and Associated Comorbidities: Standards of Care in Diabetes—2024. https://diabetesjournals.org/care/article/47/Supplement_1/S43/153945/3-Prevention-or-Delay-of-Diabetes-and-Associated
  6. Centers for Disease Control and Prevention (CDC). (2024). Diabetes risk factors. https://www.cdc.gov/diabetes/risk-factors/index.html
  7. Centers for Disease Control and Prevention (CDC). (2024). Preventing type 2 diabetes. https://www.cdc.gov/diabetes/prevention-type-2/index.html
  8. Gołąbeka KD, et al. (2019). Dietary support in insulin resistance: an overview of current scientific reports. https://advances.umw.edu.pl/pdf/2019/28/11/1577.pdf
  9. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). (2018). The A1C test & diabetes. https://www.niddk.nih.gov/health-information/diagnostic-tests/a1c-test
  10. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). (2018). Insulin resistance & prediabetes. https://www.niddk.nih.gov/health-information/diabetes/overview/what-is-diabetes/prediabetes-insulin-resistance
  11. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). (2015). Prediabetes screening: how & why. https://www.niddk.nih.gov/health-information/professionals/clinical-tools-patient-management/diabetes/game-plan-preventing-type-2-diabetes/prediabetes-screening-how-why
  12. National Health Service (NHS). (2023). What is type 2 diabetes?. https://www.nhs.uk/conditions/type-2-diabetes/
  13. Office of Disease Prevention and Health Promotion (OASH). (2024). Take steps to prevent type 2 diabetes. https://health.gov/myhealthfinder/health-conditions/diabetes/take-steps-prevent-type-2-diabetes
  14. Richter EA, et al. (2021). Interactions between insulin and exercise. https://portlandpress.com/biochemj/article-abstract/478/21/3827/230182/Interactions-between-insulin-and-exercise?redirectedFrom=fulltext
  15. Riley L, et al. (n.d.). Mean fasting blood glucose. https://www.who.int/data/gho/indicator-metadata-registry/imr-details/2380
  16. World Health Organization (WHO). (2023). Polycystic ovary syndrome. https://www.who.int/news-room/fact-sheets/detail/polycystic-ovary-syndrome