Insulin is a hormone that helps regulate blood sugar. Insulin resistance is when your cells don’t respond to this hormone the way they should.
Insulin helps your cells take up the sugar from your blood. If you have insulin resistance, your body has to work harder and produce more of the hormone to keep your blood sugar levels in check. Over time, this can increase your risk of developing prediabetes and type 2 diabetes.
Both genetic and lifestyle factors can increase your risk of insulin resistance.
These risk factors include overweight and obesity, a family history of diabetes, and a lack of physical activity.
If you do have insulin resistance — or you are worried you might — there are things you can do to help reverse it to reduce your risk of developing prediabetes or type 2 diabetes.
Exercise and weight loss can naturally improve insulin resistance, and a healthy diet may be the most important factor.
You can follow some broad guidelines, such as eating whole foods and lots of non-starchy vegetables. However, experts agree that a personalized approach is more effective than general recommendations.
At ZOE, we run the largest nutrition science study in the world, with over 20,000 participants so far. Our data shows that everyone responds differently to foods. The same food could lead to a high blood sugar spike in one person but a moderate response in another.
The ZOE at-home test analyzes your blood sugar and blood fat responses to food, as well as the unique range of bacteria that live in your gut, to help you understand which foods are best for you.
You can take a free quiz to find out more.
What is insulin resistance?
After you eat, your body breaks down the carbohydrates in your food into sugars. These sugars then enter your bloodstream. As blood sugar levels rise, your pancreas releases insulin.
This hormone helps your cells take in sugar from your blood and use it for energy or store it for later use. As a result, your blood sugar levels go down.
Small rises and falls in blood sugar levels are normal, but when you experience large spikes, your body responds by releasing more insulin.
Insulin resistance happens when your cells don’t respond well to insulin and have difficulty taking up the sugar from your blood.
Causes of insulin resistance
While the direct cause of insulin resistance isn’t clear, the main risk factor is excess weight.
Other genetic and lifestyle factors related to insulin resistance include:
being 45 years or older, although the number of children with insulin resistance is on the rise
having an immediate family member, such as a sibling or parent, with diabetes
having a sedentary lifestyle
having a history of gestational diabetes
having polycystic ovary syndrome, or PCOS
having other health conditions, such as high blood pressure, high blood fat or cholesterol levels, stroke, hormone disorders, or heart disease
In addition, the risk is higher if you are African American, Alaska Native, American Indian, Asian American, Hispanic/Latino, Native Hawaiian, or Pacific Islander American.
Some of the risk factors for insulin resistance require medical tests, so talk with your doctor to discuss your specific risk level.
How do you know if you have insulin resistance?
Some people may experience darkened skin around their armpit or neck if they have prediabetes, but insulin resistance typically doesn’t cause noticeable symptoms.
Doctors don’t usually test for insulin resistance specifically, although it is possible to measure how much insulin someone has in their blood.
Instead, your healthcare professional may use a combination of tests to look for clues. These tests may include a fasting plasma glucose test, HbA1C test, or oral glucose tolerance test.
The fasting plasma glucose test and oral glucose tolerance test measure the amount of sugar in your blood at the specific time of the test. An HbA1C test shows your average blood sugar levels over weeks or months.
How to reverse insulin resistance
While you can’t change your genes, genetics is rarely your destiny. Making lifestyle changes can help reverse insulin resistance and prevent prediabetes and type 2 diabetes, even if you have a family history of these conditions.
One study, which involved more than 3,000 adults, found that people who participated in lifestyle changes, including weight loss and changing their diet, were able to lower their likelihood of developing type 2 diabetes by 58% after 3 years, compared with those who took a placebo pill.
Even 15 years later, those who participated in the program were 27% less likely to develop type 2 diabetes.
Your diet can also play a big part. For example, in one study involving almost 300 adults with type 2 diabetes, those participants who went on a strictly controlled diet plan lost an average of 22 pounds and were 20 times more likely to go into remission from type 2 diabetes within 1 year, compared with people in the control group.
If you think you may be resistant to insulin, you can take these steps to help with blood sugar control.
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1. Move more
Being physically active helps improve insulin sensitivity in the short term and long term. During exercise, your muscles take in up to five times more sugar from your blood for fuel without the need for insulin. This is a temporary effect, but it can help your body become more sensitive to insulin over time.
In the short term, evidence suggests that a single session of moderate-intensity exercise can improve insulin sensitivity by more than 50% for up to 72 hours. In addition, those who regularly participate in moderate-intensity physical activity see anywhere from a 25% to 50% increase in insulin sensitivity in the long term.
Scientists suggest that both aerobic exercises and resistance training are beneficial, and they recommend regularly participating in physical activity for maximum benefit.
2. Consider weight loss
If your weight is above a moderate range for you, weight loss may improve your insulin resistance.
In particular, experts believe that excess belly fat plays a significant role in insulin resistance.
Even if your body mass index (BMI) is within a moderate range, having a waist measurement of more than 35 inches for women and 40 inches for men is linked to insulin resistance.
Losing weight can be very challenging. What is considered an optimal weight range is different for everyone. If you’re considering losing weight, work with your healthcare provider to find out what weight range is best for your health.
3. Eat a healthy diet
While there is no one-size-fits-all diet for improving insulin resistance, the American Diabetes Association (ADA) offer general recommendations to help control blood sugar and manage your weight.
If you have insulin resistance, the ADA advise you to:
choose whole, minimally processed foods without a lot of added sugar, salt, or fat
eat high-quality sources of fiber, such as whole grains, beans, and lentils
fill your plate with non-starchy vegetables like leafy greens, tomatoes, or broccoli
reach for healthy fats commonly found in fish, nuts, seeds, and vegetable oils
The importance of personalized nutrition
While the guidelines mentioned above can be helpful for insulin resistance, experts agree that a personalized approach is more appropriate.
At ZOE, we know that everyone’s responses to food are different. The way your blood sugar responds to foods is unique to you, and a personalized approach to insulin resistance is best.
Your blood sugar — along with your blood fat responses and gut microbiome — influences which foods are best for your health.
In your gut, there are trillions of microorganisms, collectively called your gut microbiome, that are involved in many important bodily functions.
ZOE research has identified 15 “good” gut bugs linked to better health and 15 “bad” bugs linked with poorer health. Many of these bugs are related to how your body produces and responds to insulin.
The ZOE at-home test can give you personalized insights into how certain foods impact your blood sugar, blood fat, and the makeup of your gut microbiome. With the ZOE program, you can learn which foods are best for your unique biology.
Take a free quiz to learn how ZOE can help you.
Insulin helps your cells absorb the sugar in your blood to use as fuel. Insulin resistance is when your cells aren’t as sensitive to insulin as they should be. This can increase your risk of developing prediabetes and type 2 diabetes.
Excess weight is the biggest risk factor for insulin resistance.
Your genes and your ethnicity may also put you at higher risk. These are things you can’t change. But you can make lifestyle changes to your physical activity levels, weight, and diet to help reduce your risk of insulin resistance and reverse it if you have the condition.
Broad nutrition guidelines can be helpful, but experts recommend a personalized approach for the best results.
With ZOE’s at-home test, you can discover your unique blood sugar and blood fat responses to foods, as well as unlock the makeup of your gut microbiome. The ZOE program can help you learn which foods are best for your body and long-term health goals.
You can take a free quiz to see what’s possible with ZOE.
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The essential role of exercise in the management of type 2 diabetes. Cleveland Clinic Journal of Medicine. (2017). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5846677/
Type 2 diabetes. (n.d). https://www.niddk.nih.gov/health-information/diabetes/overview/what-is-diabetes/type-2-diabetes