Insulin resistance is a complex condition in which your body does not respond as it should to insulin, a hormone your pancreas makes that’s essential for regulating blood sugar levels. Several genetic and lifestyle factors can contribute to insulin resistance.
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Insulin resistance, also known as impaired insulin sensitivity, happens when cells in your muscles, fat and liver don’t respond as they should to insulin, a hormone your pancreas makes that’s essential for life and regulating blood glucose (sugar) levels. Insulin resistance can be temporary or chronic and is treatable in some cases.
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Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
Under normal circumstances, insulin functions in the following steps:
For several reasons, your muscle, fat and liver cells can respond inappropriately to insulin, which means they can’t efficiently take up glucose from your blood or store it. This is insulin resistance. As a result, your pancreas makes more insulin to try to overcome your increasing blood glucose levels. This is called hyperinsulinemia.
As long as your pancreas can make enough insulin to overcome your cells’ weak response to insulin, your blood sugar levels will stay in a healthy range. If your cells become too resistant to insulin, it leads to elevated blood glucose levels (hyperglycemia), which, over time, leads to prediabetes and Type 2 diabetes.
In addition to Type 2 diabetes, insulin resistance is associated with several other conditions, including:
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Anyone can develop insulin resistance — temporarily or chronically. Over time, chronic insulin resistance can lead to prediabetes and then Type 2 diabetes if it’s not treated or able to be treated.
Prediabetes happens when your blood glucose levels are higher than normal, but not high enough to be diagnosed as diabetes. Prediabetes usually occurs in people who already have some insulin resistance.
Prediabetes can lead to Type 2 diabetes (T2D), the most common type of diabetes. T2D happens when your pancreas doesn’t make enough insulin or your body doesn’t use insulin well (insulin resistance), resulting in high blood glucose levels.
Type 1 diabetes (T1D) happens when your body’s immune system attacks and destroys the insulin-producing cells in your pancreas for an unknown reason. T1D is an autoimmune and chronic disease, and people with T1D have to inject synthetic insulin to live and be healthy. While T1D is not caused by insulin resistance, people with T1D can experience levels of insulin resistance in which their cells don’t respond well to the insulin they inject.
Gestational diabetes is a temporary form of diabetes that can happen during pregnancy. It’s caused by insulin resistance that’s due to the hormones the placenta makes. Gestational diabetes goes away once you deliver your baby. Approximately 3% to 8% of all people who are pregnant people in the United States are diagnosed with gestational diabetes.
Healthcare providers often use a blood test called glycated hemoglobin (A1c) to diagnose diabetes. It shows your average blood sugar level for the past three months. In general:
People with Type 1 diabetes usually have a very high A1C and very high blood glucose levels upon diagnosis because their pancreas is producing very little or no insulin.
Insulin resistance can affect anyone — you don’t have to have diabetes — and it can be temporary (for example, using steroid medication for a brief period causes insulin resistance) or chronic. The two main factors that seem to contribute to insulin resistance are excess body fat, especially around your belly, and a lack of physical activity.
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People who have prediabetes and Type 2 diabetes usually have some level of insulin resistance. People with Type 1 diabetes can also experience insulin resistance.
Since there aren’t any common tests to check for insulin resistance and there aren’t any symptoms until it turns into prediabetes or Type 2 diabetes, the best way to measure the prevalence of insulin resistance is through the number of prediabetes cases. More than 84 million adults in the United States have prediabetes. That’s about 1 out of every 3 adults.
The development of insulin resistance typically increases insulin production (hyperinsulinemia) so your body can maintain healthy blood sugar levels. Elevated levels of insulin can result in weight gain, which, in turn, makes insulin resistance worse.
Hyperinsulinemia is also associated with the following conditions:
Insulin resistance is also the main feature of metabolic syndrome, which is a set of features that link excess fat around the waist and insulin resistance to increased risk of cardiovascular disease, stroke and Type 2 diabetes.
Features of metabolic syndrome include:
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You don’t have to have all four of these features to have metabolic syndrome.
If you have insulin resistance, but your pancreas can increase insulin production to keep your blood sugar levels in range, you won’t have any symptoms.
However, over time, insulin resistance can get worse, and the cells in your pancreas that make insulin can wear out. Eventually, your pancreas is no longer able to produce enough insulin to overcome the resistance, leading to elevated blood sugar (hyperglycemia), which does cause symptoms.
Symptoms of high blood sugar include:
Many people have no symptoms of prediabetes, often for years. Prediabetes may be invisible until it develops into Type 2 diabetes. Some people with prediabetes may experience the following symptoms:
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If you’re experiencing any of these symptoms, it’s important to see your healthcare provider.
Scientists still have a lot to discover about how exactly insulin resistance develops. So far, they’ve identified several genes that make a person more or less likely to develop insulin resistance. In addition, older people are more prone to insulin resistance.
Several factors and conditions can cause varying degrees of insulin resistance. Scientists believe that excess body fat, especially around your belly, and physical inactivity are the two main contributing factors to insulin resistance.
Acquired causes, meaning you’re not born with the cause, of insulin resistance include:
Your body makes hundreds of hormones, which are chemicals that coordinate different functions in your body by carrying messages through your blood to your organs, muscles and other tissues. These signals tell your body what to do and when to do it.
Issues with certain hormones can affect how well your body uses insulin. Hormonal disorders that can cause insulin resistance include:
Certain inherited genetic conditions (conditions you’re born with) can cause insulin resistance for various reasons.
There’s a group of rare related conditions described as inherited severe insulin resistance syndromes that are considered part of a spectrum. Listed from most mild to most severe, these syndromes include:
Other inherited conditions that cause insulin resistance include:
Insulin resistance is difficult to diagnose because there isn’t routine testing for it, and as long as your pancreas is producing enough insulin to overcome the resistance, you won’t have any symptoms.
As there’s no single test that can directly diagnose insulin resistance, your healthcare provider will consider several factors when assessing insulin resistance, including your:
Your healthcare provider may order the following blood tests to diagnose insulin resistance and/or prediabetes or diabetes:
Your healthcare provider may also order tests that can help diagnose other conditions that are associated with insulin resistance, such as metabolic syndrome, cardiovascular disease and polycystic ovary syndrome (PCOS).
Since not all factors that contribute to insulin resistance can be treated, such as genetic factors and age, lifestyle modifications are the primary treatment for insulin resistance. Lifestyle modifications include:
Over time, these lifestyle modifications can:
You may work with other healthcare providers, such as a nutritionist and endocrinologist, in addition to your regular doctor to come up with an individualized treatment plan that works best for you.
While there are currently no medications that treat insulin resistance specifically, your healthcare provider may prescribe medications to treat coexisting conditions. Some examples include:
Insulin resistance has several causes and contributing factors. While lifestyle changes, such as eating a healthy diet, exercising regularly and losing excess weight, can increase insulin sensitivity and decrease insulin resistance, not all causes are reversible.
Talk you your healthcare provider about what you can do to best manage insulin resistance.
Your diet has a big impact on your blood sugar and insulin levels. Highly processed, high-carbohydrate and high-fat foods require more insulin.
In general, eating foods that have a low to medium glycemic index and limiting foods that have a high glycemic index can help you reverse and/or manage insulin resistance. Eating foods with fiber also helps regulate blood sugar levels because it takes your body longer to digest fiber, meaning your blood sugar levels don’t spike as much.
The glycemic index (GI) is a measurement that ranks foods containing carbohydrates according to how much they affect your blood sugar levels. The Glycemic Index Foundation (GIF) classifies the GI of foods as either low, medium or high, with pure glucose generally as a reference at 100:
High-GI foods generally have a lot of carbohydrates and/or sugar and low to no fiber content. Low-GI foods generally have low amounts of carbohydrates and higher amounts of fiber.
Examples of foods with a high GI include:
Examples of foods with a low GI include:
Always talk to your healthcare provider before making extreme changes to your diet.
Certain genetic and lifestyle risk factors make it more likely that you’ll develop insulin resistance or prediabetes. Risk factors include:
People of the following racial or ethnic backgrounds are also at a higher risk of having insulin resistance or prediabetes:
Although you can’t change certain risk factors for insulin resistance, such as family history or age, you can try lowering your chances of developing it by maintaining a healthy weight, eating a healthy diet and exercising regularly.
The prognosis (outlook) of insulin resistance depends on several factors, including:
People can have mild insulin resistance that never turns into prediabetes or Type 2 diabetes. People can also have insulin resistance that’s reversible or very manageable with lifestyle changes. For some people who have inherited conditions that cause severe insulin resistance, it can be life-threatening or lead to death.
If you have insulin resistance, ask your healthcare provider about what you can expect and how best to manage it.
The majority of the complications that can result from insulin resistance are related to the development of vascular (blood vessel) complications due to elevated blood sugar levels and elevated insulin levels (hyperinsulinemia).
Not everyone who has insulin resistance will have complications. If you’ve been diagnosed with insulin resistance, Type 2 diabetes or metabolic syndrome, it’s important to see your healthcare provider regularly and follow your treatment plan to try to prevent these complications.
If you’ve been diagnosed with insulin resistance or conditions related to insulin resistance, it’s important to see your healthcare provider regularly to make sure your blood sugar levels are in a healthy range and that your treatment is working.
If you’re experiencing symptoms of high blood sugar or prediabetes, contact your healthcare provider. They can run simple tests to check your blood sugar levels.
If you have a family history of diabetes or conditions that can cause insulin resistance, talk to your healthcare provider about your risk of developing insulin resistance.
If you’ve been diagnosed with insulin resistance, it may be helpful to ask your healthcare provider the following questions:
A note from Cleveland Clinic
Insulin resistance is a complex condition that can affect your health in several ways. Since it doesn’t have any symptoms until it turns into prediabetes or Type 2 diabetes, the best thing you can do is try to prevent and reverse insulin resistance by maintaining a healthy weight, exercising regularly and eating a healthy diet. Unfortunately, though, not all causes of insulin resistance can be prevented or treated. If you have any questions about your risk of developing insulin resistance or conditions associated with it, talk you your healthcare provider. They’re there to help you.
Last reviewed on 12/16/2021.
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