When the body doesn’t respond appropriately to insulin, this is called insulin resistance. It’s estimated that about 40% of American adults without diabetes have insulin resistance (Journal of Clinical Endocrinology & Metabolism).
Insulin resistance is linked closely with prediabetes and type 2 diabetes. If cells become too resistant to insulin, this increases blood sugar levels, and if left untreated or poorly managed, leads to type 2 diabetes.
To truly understand what it means to be insulin resistant and how to identify signs and risk factors, let’s explore insulin and its role in the body. Insulin is a hormone that the pancreas produces, and it holds the critical responsibility of regulating blood sugar 24/7.
Here’s what happens when the body responds appropriately to insulin:
- You eat a meal.
- Your blood sugar rises.
- The pancreas is prompted to release insulin.
- Insulin then carries glucose (blood sugar) to the muscles, fat, and liver cells.
- Your body uses the energy it needs, then insulin helps store the rest for later use.
- Blood sugar levels decrease as insulin transports blood sugar throughout the body.
Now, in someone who is insulin resistant, the body is not properly secreting insulin into the bloodstream; this means the body is unable to properly convert food into energy. As you can imagine, this is a problem!
The body needs energy and it needs blood sugar regulation to prevent severely high or low blood sugar levels – which can lead to hyperglycemia (high blood pressure) and ultimately, type 2 diabetes. (What are the 3 most common symptoms of undiagnosed diabetes?)
Signs and Symptoms of Insulin Resistance
How does a person know if he or she is insulin resistant? Insulin resistance doesn’t always yield recognizable signs or symptoms. Some people who have insulin resistance may experience:
- Acanthosis nigricans: Darkened skin around the armpit area, neck, groin, and other areas where the skin creases
- Skin tags: Small, noncancerous growths that form where the skin creases or rubs against itself
- Still feeling hungry after meals
- Craving sweet, salty foods regularly
- Frequent urination
- Tingling sensations in hands or feet
- Hair loss
- Chronic acne
The signs and symptoms of insulin resistance can be so subtle that they go unnoticed, which is why it’s important for you to get regular blood work done with your primary care provider to monitor blood sugar levels and changes over time.
Causes and Risk Factors of Insulin Resistance
There are a number of potential causes and risk factors behind insulin resistance, including:
- Chronic stress
- Steroid use
- Eating a high calorie, high sugar diet
A person is at a higher risk of developing insulin resistance if they:
- Have a hormonal disorder, like PCOS or Cushing’s disease
- Have sleep apnea
- Smoke cigarettes
- Have a family history of diabetes
- Are over the age of 45
- Have a waist circumference larger than 40 inches (men) or 35 inches (women)
- Have a history of high blood pressure (hypertension)
- Have blood pressure of 130/80 or higher
- Have an HDL cholesterol level under 40 mg/dL in men and 50 mg/dL in women
Conditions Related to Insulin Resistance
Because insulin is an essential hormone in the body, insulin resistance is related to a number of health conditions, including type 1 diabetes, type 2 diabetes, prediabetes and PCOS.
Insulin Resistance, Prediabetes, and Type 2 Diabetes
Untreated insulin resistance can lead to type 2 diabetes. When there’s a lot of glucose in the bloodstream, the pancreas pumps out a bunch of insulin, which rushes into the bloodstream to regulate blood sugar levels and correct the problem.
When a person continues to eat high calorie, high sugar foods, and insulin is constantly being pumped into the bloodstream, the body cells stop responding to insulin – making them insulin resistant.
Blood sugar continues rising, without regulation, which causes blood sugar to be stored in the fat cells as a last resort. This leads to weight gain, and eventually, prediabetes and type 2 diabetes.
Insulin Resistance and Type 1 Diabetes
While insulin resistance isn’t a cause of type 1 diabetes, people with type 1 diabetes may be genetically predisposed to insulin resistance.
People who have type 1 diabetes who are also insulin resistant will require a higher dosage of insulin in order to regulate blood sugar than those who are just insulin resistant. Some research has also indicated that “insulin resistance is a factor in cardiovascular disease, or heart disease, and other complications in people with type 1 diabetes” (American Diabetes Association).
Insulin Resistance and PCOS
PCOS (polycystic ovary syndrome) is a hormone imbalance condition that affects women and is caused by an excess of androgen in the body. Androgen is a group of male sex hormones that women naturally have in small amounts.
When androgen levels are above the healthy range, this can prevent the body from ovulating and cause a number of hormone-related symptoms, including hair thinning on the head, facial hair growth, irregular periods, and weight gain.
While high insulin can be the cause of PCOS, it can also be the symptom. Insulin resistance is present in 70-95% of people with obese PCOS and 30-75% of people with lean PCOS (National Library of Medicine).
Women with insulin resistance are at a higher risk of developing PCOS, and women with PCOS are at a higher risk of developing insulin resistance, as well as type 2 diabetes.
How Insulin Resistance is Diagnosed
Because insulin is a hormonal substance, insulin resistance is diagnosed by an endocrinologist. When you visit one of our experienced endocrinologists in Orlando, he or she will assess your health history, as well as any risk factors you may have.
Your doctor may perform a physical exam and order blood work, based on specific risk factors you may have.
As a part of your physical exam, your endocrinologist may weigh you and check your blood pressure. He or she may assess for common signs or symptoms of insulin resistance, such as obesity, acanthosis nigricans (dark spots in skin creases) and skin tags.
Laboratory tests may include a hemoglobin A1c test, fasting plasma glucose (FPG) test, and/or an oral glucose tolerance test (OGTT).
Hemoglobin A1c Test
A hemoglobin A1C test measures your average blood sugar levels over a span of 2 to 3 months. (Hemoglobin is the protein found in our red blood cells.) When blood sugar builds up in the bloodstream, glucose binds to hemoglobin.
The A1C test measures the amount of hemoglobin in the body, providing a percentage that reflects blood sugar levels. Normal A1C levels are below 5.7%. If the results are over the healthy range, between 5.7 and 6.4%, this is considered prediabetes. Over 6.4% is considered diabetes.
Fasting Plasma Glucose (FPG) Test
The FPG test checks your fasted glucose levels. This test requires a person to fast (not eat or drink anything besides water) for 8 hours prior to the test. After this period, the patient drinks a sugary drink, then has their blood drawn.
Eating food increases blood glucose, which is why it’s important to fast before this test. This way, food won’t affect blood sugar and lab results will show an accurate snapshot of your levels.
- Test results between 70-99 mg/DL (milligrams per deciliter) are considered normal.
- FPG results between 100-125 mg/DL indicate potential for prediabetes.
- FPG results greater than 126 mg/DL indicate diabetes.
Oral Glucose Tolerance Test (OGTT)
The oral glucose tolerance test determines whether the body is able to use glucose properly as their primary source of energy. With this test, the patient will first take an FPG test to measure fasting blood glucose levels.
The patient then drinks a sweet liquid that contains a certain amount of glucose. They will have their blood drawn after drinking the liquid, then have another blood sample taken 1 to 2 hours after the first drink. Some patients may be required to take another blood sample to gain a more accurate picture of their glucose tolerance.
Once all of the necessary samples are taken, the tests are complete. When the results come back, your doctor will compare your pre-test glucose levels to your levels taken during the test. This will determine the body’s ability to convert glucose to energy, and indicate the presence of pre-diabetes or diabetes.
How Insulin Resistance is Treated
If we catch insulin resistance in its early stages, we can develop a lifestyle plan that optimizes your diet and exercise to help reverse insulin resistance and prevent diabetes!
This is why it’s essential that you meet with your primary care provider regularly and get routine blood work done to monitor your blood sugar and insulin. Everyone should visit their primary care provider (at least) once a year for blood work. Depending on any risk factors and/or pre-existing conditions you may have, your doctor may advise that you visit him or her for more frequent tests/assessments.
At UCF Health, our board-certified specialists want what’s best for your health. We always aim for healthy lifestyle changes before medications (depending on the severity of your condition) to create sustainable health solutions that treat the source of the problem.
To prevent insulin resistance, prediabetes and type 2 diabetes, it’s important that you make healthy, permanent lifestyle changes.
- Eat a more nutritious, balanced diet with reduced carbs and sugars.
- Commit to regular exercise. Aim for at least 30 minutes a day of moderate exercise, most days of the week. If you’re currently living a sedentary lifestyle, you can take steps to gradually increase your physical activity. Start with 10 minutes one day, then aim for 15 minutes, then increase to 20 minutes, until you reach 30 minutes a day.
- Stop smoking! Smoking is a non-negotiable factor here. Nicotine actually inhibits your cells from responding to insulin (CDC) – which is a direct path to insulin resistance.
- Manage stress in healthier ways. Chronic stress can lead to a number of challenging health conditions, including insulin resistance and heart disease. When you’re stressed, the body releases hormones (cortisol and adrenaline) – which can overwhelm the body and make it more challenging for the body to respond to insulin (Diabetes UK). Commit to healthy ways of managing stress, and know how to prevent heart disease.
We’ll work with you to create a practical lifestyle plan that improves your diet, gets you active, lowers your weight, minimizes risk factors for heart disease, and helps improve your body’s response to glucose and insulin.
While there are no medications to treat insulin resistance specifically, if lifestyle changes don’t work, your doctor may prescribe a diabetes medication, such as metformin or thiazolidinediones (TZDs), to reduce insulin resistance. Lipid-lowering medication has also proven to help blood sugar control in people with type 2 diabetes by lowering triglycerides and improving insulin sensitivity over time (Penn Medicine).
Schedule an Appointment Today
The best treatment route for you will depend on your health history, lab test results, symptoms, and treatment goals. When you meet with one of our top-rated endocrinologists, he or she will get to know you and your needs, and develop a plan to help you manage, treat, or prevent insulin resistance. We want to help you live your greatest quality of life.