Insulin resistance is the foundation of many chronic health conditions.
Conditions such as diabetes, heart disease, obesity, and metabolic syndrome, are more prevalent than ever these days.
In fact, about 1 in 3 adults in the US has prediabetes, which stems directly from insulin resistance, and puts you at risk of developing diabetes (1).
Let’s take a look at insulin resistance, risk factors and symptoms, and what you can do to prevent/reduce it.
What is Insulin Resistance?
In short, insulin resistance is when your body becomes desensitized to insulin.
Insulin is a hormone secreted by the pancreas. Its function is to help glucose (sugar) enter your liver, fat, and muscle cells, where glucose is broken down for energy.
Glucose is ingested when you eat food containing carbohydrates, and is absorbed into your blood stream, causing your blood glucose (blood sugar) levels to rise. Your pancreas will then release insulin which lowers your blood sugar as the glucose is broken down and used up in the cells.
However, if you are insulin resistant, your cells will not respond well to insulin when it is released, and glucose cannot enter the cells to be used up. Blood glucose levels will remain high, and your pancreas will then produce more insulin in an attempt to regulate your blood sugar.
Your pancreas can increase insulin production to keep your blood sugar in check for a while, but it will reach a point where it can’t keep up any more.
Without intervention, blood sugar levels will continue to rise and you may develop prediabetes and diabetes.
Insulin resistance can contribute to a plethora of health issues including:
- Prediabetes: higher than normal blood glucose levels, but not yet high enough for diabetes.
- Type 2 diabetes: too high blood glucose levels in the body because the body is not making enough insulin, or insulin is not being used properly.
- Cardiovascular disease (heart disease, high blood pressure, stroke, etc.) (2)
- Weight gain, obesity, metabolic syndrome
- Non-alcoholic fatty liver disease (NAFLD) (3)
- Cancer (4)
- Memory decline (5)
Insulin Resistance Symptoms and Signs
Insulin resistance can be caused by a variety of genetic and lifestyle factors.
Risk factors for insulin resistance include:
- Obesity or overweight
- Low physical activity
- High carbohydrate diet
- Age – risk increases with age, 45 and up are at a greater risk
- Ethnicity – African American, Hispanic, Asian American, American Indian, and Pacific Islander are at a greater risk
- Family history of diabetes
- History of gestational diabetes
- Conditions such as high blood pressure, high cholesterol, heart disease, metabolic syndrome
- Certain medications such as glucocorticoids (6)
- Hormonal disorders such as Cushing’s syndrome and acromegaly
- Polycystic ovary syndrome (PCOS) (7)
- Sleep disorders such as sleep apnea (8)
It turns out there are no crystal clear symptoms to tell if you have insulin resistance. Blood glucose levels are not high enough to cause adverse effects such as diabetes symptoms. This makes it easy for insulin resistance and prediabetes to go undetected.
In fact, you could be insulin resistant for years without knowing it.
The best way to watch out for insulin resistance and prediabetes may be to examine the risk factors. If you fall under, or have been struggling with, many of those risk factors, you may have some level of insulin resistance. Talk to your doctor about getting your blood sugar tested.
In particular, signs of metabolic syndrome are the most common clues that you may be insulin resistant and/or prediabetic. Risk factors include a waist measurement of 35 inches or more for women or 40 inches or more for men, plus high triglycerides, low HDLs, high blood pressure, and/or high blood sugar (9).
When insulin resistance develops into prediabetes, one visible symptom experienced by some people is a skin condition called acanthosis nigricans. This appears as darkened skin in certain areas such as the armpit and neck, as well as possibly skin tags in these areas.
Additionally, prediabetes can be diagnosed with a blood test.
Common tests for prediabetes include:
- A1C test: measures your average blood sugar level for the past 2-3 months.
- Fasting plasma glucose test: measures your blood sugar after not eating for at least 8 hours.
- Oral glucose tolerance test: after the fasting glucose test, you drink a sugary solution and take another blood test two hours later.
Once blood sugar levels get high enough to develop into diabetes, symptoms may include:
- Increased hunger/thirst
- Brain fog
- Frequent urination
- Frequent infections
- Tingling in hands and feet
How to Reduce Insulin Resistance
If you think you may be at risk, or are struggling with insulin resistance, the best course of action to reduce insulin resistance and prevent diabetes is to focus on diet and exercise.
Lifestyle changes have been shown to be very effective in the prevention of diabetes development. One study showed that individuals at a high risk of diabetes were able to reduce their risk of developing diabetes by 27% by losing 5-7% of their body weight through dietary and exercise intervention (10)
If you are overweight or obese, weight loss is very important. Even a small reduction in weight can reduce your risk of insulin resistance and diabetes.
Furthermore, another study showed that diet and exercise combined have the greatest effect on improving insulin resistance in obese individuals (11). This study found that diet-induced weight loss (10% of body weight) significantly improved insulin resistance, but diet-and-exercise-induced weight loss had an even greater improvement on insulin resistance. Increased exercise with no weight loss did not have an effect on insulin resistance.
Diet and exercise together are very important for combatting insulin resistance.
Diet may differ between individuals, but generally, a balanced diet of whole foods is best.
Also opt for complex and fibrous carbohydrates as opposed to simple sugars; simple sugars cause blood sugar spikes which takes a toll on insulin and elevates blood sugar levels.
Check out this post on sugar for tips on how to reduce the amount of added sugar you consume.
In terms of exercise, it is generally recommended to get in at least 150 minutes of physical activity a week, or 30 min/day, 5 days/week.
Insulin resistance is a condition where the body does not respond properly to insulin. It can lead to various health issues including diabetes. Certain genetic and lifestyle factors can put you at increased risk of insulin resistance. Diet and exercise are the best tools for managing and preventing insulin resistance and associated complications.
Let me know in the comments if you liked this article on insulin resistance symptoms and prevention, or if you have any questions. I’d love to hear from you!