Insulin Resistance

What Is Insulin Resistance?

Insulin resistance is when cells in your muscles, fat, and liver don’t respond well to insulin and can’t use glucose from your blood for energy. To make up for it, your pancreas makes more insulin. Over time, your blood sugar levels go up.

Insulin resistance syndrome includes a group of problems like obesity, high blood pressure, high cholesterol, and type 2 diabetes. It could affect as many as 1 in 3 Americans. You might also hear it called metabolic syndrome.

Symptoms of Insulin Resistance

You can't tell that you have insulin resistance by how you feel. You'll need to get a blood test that checks your blood sugar levels.

Likewise, you won’t know if you have most of the other conditions that are part of insulin resistance syndrome (high blood pressure, low "good" cholesterol levels, and high triglycerides) without seeing your doctor.

Some signs of insulin resistance include:

• A waistline over 40 inches in men and 35 inches in women
• Blood pressure readings of 130/80 or higher
• A fasting glucose level over 100 mg/dL
• A fasting triglyceride level over 150 mg/dL
• A HDL cholesterol level under 40 mg/dL in men and 50 mg/dL in women
• Skin tags
• Patches of dark, velvety skin called acanthosis nigricans

Risk Factors and Causes of Insulin Resistance

Things that can make this condition more likely include:

• Obesity, especially belly fat
• Inactive lifestyle
• Diet high in carbohydrates
• Gestational diabetes
• Health conditions like nonalcoholic fatty liver disease and polycystic ovary syndrome
• A family history of diabetes
• Smoking
• Ethnicity -- it’s more likely if your ancestry is African, Latino, or Native American
• Age -- it’s more likely after 45
• Hormonal disorders like Cushing’s syndrome and acromegaly
• Medications like steroids, antipsychotics, and HIV medications
• Sleep problems like sleep apnea

Diagnosis and Tests for Insulin Resistance

Your doctor will use these things to diagnose insulin resistance:

• Questions. They’ll want to know about your family's medical history.
• Physical exam. They’ll weigh you and check your blood pressure.
• Blood tests. You might get:
• Fasting plasma glucose test. This test measures your blood sugar after you haven’t eaten for at least 8 hours.
• Oral glucose tolerance test. First, you'll take the fasting glucose test. Then you'll drink a sugary solution. Two hours after that, you'll take another blood test.
• Hemoglobin A1c test. This blood test shows your average blood sugar level for the past 2 to 3 months. Doctors use it to diagnose prediabetes or diabetes. If you have diabetes, it helps show whether it's under control. You may need to take the test again to confirm the results.