Diabetes: What’s Insulin Resistance Got To Do with It?

Invisible changes in the body begin long before a person is diagnosed with type 2 diabetes. That's both bad news (no symptoms mean you won't know you have it) and good news (you can prevent or delay it if you're at risk). One of the most important unseen changes? Insulin resistance.

Insulin in a Nutshell

Insulin is a key player in developing type 2 diabetes. This vital hormone—you can't survive without it—regulates blood sugar (glucose) in the body, a very complicated process. Here are the high points:

• The food you eat is broken down into glucose.
• Glucose enters your bloodstream, which signals the pancreas to release insulin.
• Insulin helps glucose enter the body's cells so it can be used for energy.
• Insulin also signals the liver to store glucose for later use.
• Glucose enters cells, and glucose levels in the bloodstream decrease, signaling insulin to decrease too.
• Lower insulin levels alert the liver to release stored glucose so energy is always available, even if you haven't eaten for a while.

That's when everything works smoothly. But this finely tuned system can quickly get out of whack, as follows:

• A lot of glucose enters the bloodstream.
• The pancreas pumps out more insulin to get glucose into cells.
• Over time, cells stop responding to all that insulin—they've become insulin resistant.
• The pancreas keeps making more insulin to try to make cells respond.
• Eventually, the pancreas can't keep up, and glucose keeps rising.

Now What?

Lots of glucose in the bloodstream is very damaging to the body and needs to be moved into cells as soon as possible. There's lots of insulin, too, telling the liver and muscles to store glucose. When they're full, the liver sends the excess glucose to fat cells to be stored as body fat. Yep, weight gain. And what's more serious, the stage is set for type 2 diabetes.

How do you find out if you're insulin resistant? No one test will tell you, but if you have high glucose levels, high triglycerides (a kind of blood fat), high LDL ("bad") cholesterol, and low HDL ("good") cholesterol, your health care provider may determine you have insulin resistance.

Important note: Type 1 diabetes is different; it's caused by an autoimmune reaction (the body attacks itself by mistake). People with type 1 diabetes don't make enough insulin and need to take it to survive.

Why You?

It isn't clear exactly what causes insulin resistance, but a family history of type 2 diabetes, being overweight (especially around the waist), and being inactive all can raise the risk.

You do not have to be overweight to have insulin resistance. You can't tell if someone has insulin resistance by looking at them.

What You Can Do

If you have insulin resistance, you want to become the opposite—more insulin sensitive (cells are more effective at absorbing blood glucose so less insulin is needed).

Physical activity makes you more sensitive to insulin, one reason why it's a cornerstone of diabetes management (and good health in general!). Don't wait until you're diagnosed with diabetes to start moving more. The earlier you take action (literally), the better off you'll be.

Weight loss is important too, as is avoiding high blood sugar, reducing stress, and getting enough sleep (physical activity can help you get more zzz's too).

These lifestyle changes really work. Talk with your health care provider about how to get started.

Find Out More

CDC's Division of Diabetes Translation
Prediabetes and Insulin Resistance
What is Prediabetes and are You at Risk?
Preventing Diabetes Tips Sheets
Diabetes Features & Spotlights
CDC Diabetes on Facebook
@CDCDiabetes on Twitter