What Is Insulin Resistance?
Insulin resistance is a condition in which the cells in your muscles, fat and liver don't respond to insulin the way they should, so your body needs more insulin to keep blood sugar (glucose) in a healthy range. Insulin, a hormone made by the pancreas, acts like a key that lets blood sugar into your cells for energy.
At first, the pancreas makes extra insulin to compensate, so blood sugar stays in a healthy range and there are no symptoms. Over time, the pancreas may not keep up, and blood sugar rises to prediabetes and, for some people, type 2 diabetes.
Insulin Resistance at a Glance
| Also called | Impaired insulin sensitivity |
|---|---|
| Cause | Not fully understood. Genes, older age, excess weight and inactivity all play a role. |
| Who gets it | Adults and children. Risk rises with age and excess weight. |
| Is it serious? | It can be. It sets the stage for prediabetes and type 2 diabetes. Some research links it to heart disease. |
| Symptoms | Usually none |
| Diagnosis | No routine test. Clinicians check blood sugar (A1C or fasting glucose) and cholesterol and triglyceride levels. |
| Treatment | Physical activity, weight loss if needed, healthy eating, enough sleep and stress management. Sometimes metformin. |
| ICD-10 code | E88.819 (insulin resistance, unspecified) |
What Are the Symptoms of Insulin Resistance?
Insulin resistance usually causes no symptoms, and you can't tell whether someone has it by looking at them. One visible sign in some people is acanthosis nigricans: darker, thick, velvety skin in the armpits, groin and neck folds. It often fades when the underlying cause is treated.
What Causes Insulin Resistance?
The cause of insulin resistance isn't fully understood, but genes, aging and lifestyle all contribute. Some researchers think extra fat tissue may cause inflammation or other cell changes that lead to it. You don't have to have overweight to have insulin resistance.
Your risk is higher if you:
- Have overweight, obesity or a large waist size
- Are 35 or older (children and teens can also develop it)
- Have a family history of diabetes
- Are African American, American Indian, Asian American, Hispanic, Latino or Pacific Islander
- Aren't physically active, or smoke
- Had gestational diabetes or gave birth to a baby weighing 9 pounds or more
- Have polycystic ovary syndrome (PCOS) or sleep apnea
- Take certain medicines long term, such as glucocorticoids
What Health Problems Can Insulin Resistance Cause?
Insulin resistance can lead to prediabetes and type 2 diabetes. It is also linked to high blood pressure, unhealthy cholesterol and triglyceride levels, metabolic syndrome and fatty liver disease (MASLD). Some research links insulin resistance to heart disease even without diabetes. People with prediabetes have a high chance of developing type 2 diabetes within 5 to 10 years.
How Is Insulin Resistance Diagnosed?
Insulin resistance usually isn't tested for directly; instead, clinicians check for its effects on blood sugar. The direct test is used mainly in research. Your clinician may order:
- A1C test: average blood sugar over the past 3 months
- Fasting plasma glucose test: blood sugar after at least 8 hours without food
- Cholesterol and triglyceride tests: blood fats may rise with insulin resistance
Testing is suggested for adults 35 and older, and for people with overweight or obesity plus other risk factors. With prediabetes, testing for type 2 diabetes every year is recommended.
How Is Insulin Resistance Treated?
Insulin resistance is treated mainly with lifestyle changes that make cells more sensitive to insulin. No medicine is approved specifically for it.
- Physical activity: probably the best way to combat insulin resistance. For adults with overweight or obesity at high risk of type 2 diabetes, the American Diabetes Association's 2026 Standards of Care set a goal of at least 150 minutes a week of moderate-intensity activity, such as brisk walking.
- Weight loss: at least 5% to 7% of starting weight if you have overweight or obesity, about 10 to 14 pounds for a 200-pound person
- Healthy eating: for prediabetes, the Standards of Care name Mediterranean and low-carbohydrate eating patterns as evidence-based options
- Medicines: metformin and thiazolidinediones (TZDs) lower blood sugar partly by reducing insulin resistance. Weight-loss medicines or bariatric surgery can help in some cases.
Can You Prevent Insulin Resistance?
You may be able to prevent insulin resistance by reaching and keeping a healthy weight and staying active. Stopping smoking also removes one risk factor. If you already have prediabetes, the CDC-led National Diabetes Prevention Program can lower your risk of type 2 diabetes by 58% (71% if you're over 60).
When Should You See a Clinician About Insulin Resistance?
See a clinician about insulin resistance if you have signs or risk factors, because it usually causes no symptoms. Make an appointment if you:
- Notice thick, dark, velvety skin on your neck, armpits or groin
- Have risk factors, such as PCOS or past gestational diabetes, and haven't had your blood sugar tested
- Were told you have prediabetes or high triglycerides
Insulin Resistance vs. Prediabetes, Type 2 Diabetes and Metabolic Syndrome
Insulin resistance is the underlying problem; prediabetes and type 2 diabetes are later stages in which blood sugar rises, and metabolic syndrome is a cluster of conditions also called insulin resistance syndrome.
| Condition | What it is | How it's identified |
|---|---|---|
| Insulin resistance | Cells respond poorly to insulin; blood sugar may be normal | No routine clinical test |
| Prediabetes | Blood sugar higher than normal but not high enough for diabetes | A1C 5.7% to 6.4%, or fasting glucose 100 to 125 mg/dL |
| Type 2 diabetes | The pancreas can no longer overcome the resistance | A1C 6.5% or above, or fasting glucose 126 mg/dL or above |
| Metabolic syndrome | A group of conditions that raise heart disease, diabetes and stroke risk. Also called insulin resistance syndrome. | Three or more of: large waistline, high blood pressure, high blood sugar, high triglycerides, low HDL cholesterol |
Insulin Resistance Evaluation at GENEVA
At GENEVA Primary Care & Med Spa in Alpharetta, GA, a GENEVA provider evaluates concerns about insulin resistance, including your risk factors and blood sugar. Based on that evaluation, your provider recommends treatment at GENEVA or a referral to a specialist.
Learn more about chronic disease management and physical exams at GENEVA. GENEVA serves patients from Alpharetta, Johns Creek, Milton, Roswell and Cumming.
Related Terms
- HbA1c test
- Diabetes screening
- Blood sugar monitoring
- Triglycerides
- HDL cholesterol
- Chronic disease management
Insulin Resistance FAQs
Is insulin resistance serious?
Insulin resistance can be serious because it sets the stage for prediabetes and type 2 diabetes, even though it usually causes no symptoms. It is also linked to high blood pressure, unhealthy cholesterol and triglyceride levels and fatty liver disease, and some research links it to heart disease even without diabetes. People with prediabetes have a high chance of developing type 2 diabetes within 5 to 10 years. If you have risk factors, ask a clinician about blood sugar testing.
Can insulin resistance be reversed?
Yes, insulin resistance can often be reversed by making your cells more sensitive to insulin, mainly through physical activity and weight loss. For people with prediabetes, the CDC recommends at least 150 minutes a week of brisk walking or similar activity and, if you have overweight, losing 5% to 7% of your body weight. Eating more non-starchy vegetables, fruits, whole grains and lean proteins, getting enough sleep and managing stress also help. The American Diabetes Association notes it may not be possible to defeat insulin resistance entirely. Ask a clinician which changes fit your health.
What causes insulin resistance?
The exact cause of insulin resistance isn't fully understood, but genes, older age, excess weight and physical inactivity all raise the risk. Some researchers think extra fat tissue may cause inflammation that contributes. Other risk factors include a family history of diabetes, smoking, past gestational diabetes, PCOS, sleep apnea and long-term use of certain medicines, such as glucocorticoids. You don't have to have overweight to develop insulin resistance. Talk with a clinician if you have several risk factors.
Is insulin resistance the same as prediabetes?
No, insulin resistance and prediabetes are related but not the same. Insulin resistance means your cells don't respond well to insulin, and blood sugar may still be normal. Prediabetes means blood sugar is already higher than normal but not high enough for diabetes: an A1C of 5.7% to 6.4% or a fasting glucose of 100 to 125 mg/dL. Insulin resistance often comes first and can lead to prediabetes. People with prediabetes should be tested for type 2 diabetes every year.
Is there a blood test for insulin resistance?
No standard blood test for insulin resistance is used in routine care. The reference test, called the hyperinsulinemic-euglycemic clamp, is used mainly in research. Lab-based estimates, such as HOMA-IR and the triglyceride-glucose (TyG) index, exist. However, a 2020 systematic review of the TyG index found that cutoff values varied between studies and noted the lack of a standardized definition of insulin resistance. Instead, clinicians usually order an A1C or fasting glucose test plus cholesterol and triglyceride tests. Ask your clinician which tests fit your risk.
Can a primary care provider diagnose and treat insulin resistance?
Yes, a primary care provider can usually evaluate insulin resistance and order the blood tests used to find prediabetes and type 2 diabetes. At GENEVA in Alpharetta, a provider reviews your risk factors and lab results, then recommends treatment at GENEVA or a referral to a specialist. Testing is suggested for adults 35 and older and for people with overweight or obesity plus other risk factors. Treatment usually starts with physical activity and weight loss, and some people may also be prescribed metformin.