What is insulin resistance? A Mayo Clinic expert explains

Hello. I'm Dr. Eleanna De Filippis, an endocrinologist at Mayo Clinic. In this video, we'll cover the basics of insulin resistance. What is it? Who gets it? The symptoms, diagnosis and treatment. Whether you're looking for answers for yourself or someone you love, we're here to give you the best information available. To understand insulin resistance, often referred to as prediabetes, let's first talk about what insulin does. When you eat food, your body converts that food into dietary sugars. Insulin is a hormone released by the pancreas that tells your cells to open up to that sugar and convert it into energy. With insulin resistance, the cells don't react, and don't open up, resulting in excessive sugar in the blood. Over time, the pancreas keeps trying to regulate the blood sugar, producing more and more insulin until it wears out and can't produce large amounts of insulin anymore. As a result, blood sugar levels increase to the point of being in the diabetic range.

Anyone can become insulin-resistant. In particular, people with excess weight are at a higher risk, compared to the general population. Risk is further increased with a family history of type two diabetes, age over 45, African, Latino or Native American ancestry, smoking, and certain medications, including steroids, anti-psychotics, and HIV medication. There are other medical conditions associated with insulin resistance, like obstructive sleep apnea, fatty liver disease, polycystic ovarian syndrome, also known as PCOS, Cushing's syndrome, and lipodystrophy syndromes. Lipodystrophy syndromes are conditions that cause abnormal fat loss. So carrying either too much or not enough fat tissue in your body can be associated with insulin resistance.

Very often people with insulin resistance don't have any symptoms at all. It is usually picked up by their doctor during an annual health exam or routine blood work. There are some signs of insulin resistance that your doctor may look for. These includes a waistline over 40 inches in men, and a waistline over 35 inches in women. Skin tags or patches of dark velvety skin called acanthosis nigricans. A blood pressure reading of 130 over 80 or higher. A fasting glucose level equal or above 100 milligrams per deciliter. Or a blood sugar level equal or above 140 milligrams per deciliter two hours after a glucose load test. An A1C between 5.7% and 6.3%. A fasting triglycerides level over 150 milligram per deciliter. And an HDL cholesterol level under 40 milligrams per deciliter in men, and an HDL cholesterol level under 50 milligrams per deciliter in women.

If your doctor spots these symptoms, they may follow up with a physical exam and a variety of blood tests that measure the levels of glucose, or sugar, in your blood and/or your tolerance to that glucose. Or more recently, a blood test called hemoglobin glycosylated A1C, often simply referred to as A1C.

Reversing insulin resistance and preventing type two diabetes is possible through lifestyle changes, medication, or sometimes both. Healthy bodies come in different shapes and sizes. Losing weight through drastic means can be dangerous and counterproductive. Instead, get ideas from a doctor or a nutritionist about ways to incorporate healthy foods like fruits, vegetables, nuts, beans, and lean proteins into your meals. Also, consider incorporating exercise and movement into your day-to-day life in ways that make you feel good.

Even though permanently defeating insulin resistance isn't always possible, you can help your body to be more receptive to insulin. Listen to your body, reduce stress, give it the nutrition and activity it desires. If you'd like to learn even more about insulin resistance, watch our other related videos or visit mayoclinic.org. We wish you well.