What Happens to Your Body When You Have Insulin Resistance

There’s not a lot of good news when it comes to insulin resistance. After all, the condition can raise your risk for high blood pressure and cholesterol, increased inflammation, fatty liver disease and prediabetes and type 2 diabetes. And that’s why it’s important to prevent insulin resistance—or reverse it if you have it.

Understanding what happens to your body when you have insulin resistance can be helpful if you’re one of the estimated 8.5 million Americans with undiagnosed diabetes, 37.3 million with diabetes or 96 million with prediabetes, per the Centers for Disease Control and Prevention.

In this article, learn about what insulin resistance is, its role in the body, the connection to diabetes, how to recognize symptoms, when to get screened and more.

Related: 7-Day Meal Plan for Insulin Resistance

What Is Insulin Resistance?

When you eat food that contains carbohydrates, your body metabolizes those carbs into glucose (sugar), its preferred source of energy. In response, your pancreas releases a hormone called insulin. Insulin helps move glucose from your bloodstream into cells where it can be used for energy. The hormone will also package extra glucose to be stored in the liver when needed. If your cells don’t respond properly to insulin, however, you can develop insulin resistance, according to the National Institute of Diabetes, Digestive and Kidney Diseases.

Why does it happen? “If we eat too much food, our cells get tired of seeing too much glucose and resist opening up to insulin,” says Michael Henderson, M.D., who specializes in diabetes and practices in Wichita Falls, Texas. As a result, glucose remains in the blood and the pancreas responds by making more insulin to compensate. Overtime if your pancreas can't keep up with this demand, your blood sugars will rise.

When glucose levels remain high despite a high production of insulin, you can develop prediabetes or type 2 diabetes, says Lauren Plunkett, RDN, a certified diabetes care and education specialist and person living with type 1 diabetes based in the Minneapolis-St. Paul-area. “Insulin resistance may also be present in type 1 diabetes, a condition in which the pancreas is no longer producing insulin,” she says. 

What Happens to Your Body When You Have Insulin Resistance

Most of the time, insulin resistance occurs without any symptoms, says the NIDDK, which is why regular checkups with your doctor are so important.

While you can have insulin resistance without having diabetes, having symptoms—like those below—can be a warning sign that you’re at risk of developing type 2 diabetes or already have it. Here’s what you need to know.

You May Have No Symptoms 

Some people with insulin resistance don’t know they have it until they have bloodwork done, and blood sugar levels come back abnormally high. The good news is that detecting insulin resistance early can help you hop on a treatment plan. “It's possible to reverse insulin resistance, and the best time to do it is as soon as possible,” Henderson says.

You May Feel Tired and Hungry

Glucose is needed for energy, but when cells are resistant to insulin, glucose remains in the bloodstream, and you can feel fatigued and hungrier than usual.

You May Notice Darkened Skin  

Having dark, velvety areas on your skin are a key indicator of insulin resistance. This is called acanthosis nigricans. “These patches may also appear on skin folds and other areas such as the armpits, groin, elbows, face, knees, knuckles, soles of feet and underneath breasts,” says Maria Elena Fraga, RD, CDCES, program director of the Diabetes Alliance Program at the Mount Sinai Health System in New York City.

You May Have More Skin Tags 

Skin tags are harmless skin growths, but if you have a lot of them they could be a sign of too much insulin in your body or type 2 diabetes, according to the American Academy of Dermatology Association. These may appear in the same places as acanthosis nigricans, notes the NIDDK.

You May Gain Weight 

As insulin levels increase, sugar is packaged and stored in the liver and muscles. But there is only so much storage. “Extra insulin can make us gain weight,” says Henderson. When the liver and muscles fill up, the extra sugar is sent to fat cells to be stored as body fat. This weight gain can also make insulin resistance worse.

Risk Factors and Causes

There are many risk factors that can make you more likely to develop insulin resistance, according to the American Diabetes Association. Some include:

• Having overweight or obesity
• Being sedentary
• Having a first-degree relative (parent or sibling) with type 2 diabetes
• Being African American, Hispanic/Latino, American Indian, Asian American or Pacific Islander
• Having polycystic ovary syndrome (PCOS)
• Having had gestational diabetes (diabetes during pregnancy)
• Being over age 45

Your diet also matters when it comes to insulin resistance. “Eating more food than our body needs is the main cause of insulin resistance. Foods that can make insulin resistance worse are those high in animal fat and simple sugars (like soda, candy and pastries),” Henderson says. 

How to Diagnose Insulin Resistance

Your doctor will assess if screening for prediabetes or diabetes is necessary depending on your health and risk factors. Several blood tests can be used to check your blood sugar levels, including fasting plasma glucose and A1C tests.

Some physician’s offices offer a point-of-care hemoglobin A1C test, which is a non-fasting finger prick blood test. “The results are provided within minutes and can allow for an initial conversation with your provider on how to modify your lifestyle,” says Fraga. However, not all offices have this test available, so if your physician does not have one, they can perform a standard blood draw instead.

How to Treat and Prevent Insulin Resistance

The best treatment and prevention strategies for insulin resistance focus on lifestyle changes. Here are the top five things to do.

Eat More Plants

While there is no one-size-fits-all eating plan for insulin resistance, 2019 research in JAMA Internal Medicine shows that a plant-based diet—emphasizing whole grains, legumes, nuts, fruits and vegetables and minimal refined and processed foods—is associated with lower risk of type 2 diabetes. “Reducing the amount of refined simple sugars such as white-flour foods, sweets, cakes and cookies, juice and soda, can improve your body’s ability to regulate your blood sugar and require less insulin,” Fraga adds. Try this Quinoa-Black Bean Salad. It’s one of our top picks for lunch for people who have insulin resistance.

Exercise 

Aim for 150 minutes per week. When you’re active, muscles gobble up glucose in your blood, helping lower blood sugar, something that improves insulin sensitivity for 24 hours after activity, says the ADA. Don’t know where to start? “Low-impact movement is one of the most powerful actions a person can take to improve their health,” says Plunkett. That can include walking, swimming, biking or yoga. Focus on finding an activity you love, and aim to do it daily. Start with 10 minutes and build up from there.

Reach a Healthy Weight

Losing 5% to 7% of your body weight has been shown to treat insulin resistance and prevent diabetes, says the NIDDK. Not sure where to start? Connecting with a registered dietitian can help you develop an individualized meal plan that works for your lifestyle. Also check out these Diabetes-Friendly Weight-Loss Recipes.

Maintain a Healthy Lifestyle

Stress, sleep and smoking can worsen insulin resistance. “Take a wellness inventory of what you want to change for the better,” Plunkett recommends. For example, if you know you’re not getting the sleep you need (something that can lead to insulin resistance, says the CDC), work with your health care providers to develop a better sleep routine and implement sleep hygiene habits, such as maintaining a regular sleep schedule and limiting screen time before bed.

Related: The Best and Worst Foods for Better Sleep, According to a Doctor

Frequently Asked Questions 

Is insulin resistance the same as diabetes?

No, it’s not the same. Insulin resistance can lead to the development of diabetes. With lifestyle changes, such as improving your diet and increasing physical activity, you can reverse insulin resistance.

What are the signs of insulin resistance?

Insulin resistance usually does not have symptoms. However some possible symptoms include thick patches of dark skin in skin folds like the neck, skin tags, weight gain, fatigue and hunger.  

What’s the main cause of insulin resistance?

Insulin resistance develops due to genetics, diet and lifestyle. One of the main causes of insulin resistance is excessive calorie intake. People with insulin resistance may also have high triglycerides (a type of fat in the blood), low “good” HDL cholesterol, high blood pressure, excess abdominal fat and elevated blood sugar. 

Do foods cause insulin resistance?

A specific food will not directly cause insulin resistance, but certain foods can make insulin resistance worse. And regularly eating more calories than your body needs can cause weight gain, a main contributor to insulin resistance. Reducing intake of sweets such as soda and candy, as well as processed meat, fried foods and high-fat meat, can reduce your overall calorie intake to help you maintain a healthy weight.

How can you fix insulin resistance?

You can prevent, treat and potentially reverse insulin resistance by adopting lifestyle behaviors that will contribute to your overall health and well-being. Key factors include eating more fiber-rich foods (fruits, vegetables, whole grains, nuts and seeds), moving more and sitting less, reducing stress and getting adequate sleep. 

The Bottom Line

Insulin resistance develops slowly over time and can increase the risk of prediabetes and diabetes. The earlier you address insulin resistance the better. Lifestyle modifications, such as eating more plants, exercising more, weight loss, managing stress and improving sleep can prevent, treat and reverse insulin resistance.