How To Treat Insulin Resistance?

Insulin resistance is considered to be the first step to many chronic diseases such as heart disease, diabetes, cancer and dementia. Unfortunately, it is a condition that many do not know anything about as there are no obvious symptoms initially and is not routinely assessed for by doctors.

This article aims to give you some knowledge and awareness about insulin resistance. More importantly, I hope to give you the tools to recognise and reverse this key metabolic disorder.

By optimising your insulin sensitivity you’ll be able to improve your health, your physical and cognitive performance, and so ensure a longer and higher quality of life that defies your age.

What is insulin resistance?

Insulin resistance is a complex neuroendocrine condition that is still yet to be fully understood. Essentially it is where the action of insulin on your cells is impaired or less effective.

When you eat, the levels of glucose (sugar) in your blood rise. Your body likes to keep blood glucose in a tight range as high levels can be toxic. So to compensate for this rise, your pancreas (a hormone-secreting organ) increases the release of insulin into your blood.

Insulin is a hormone that signals your cells to take in the glucose from the blood. This mainly occurs in your muscles, liver and fat tissue. The glucose is stored as glycogen in your muscles and liver. In your fat tissue, it is stored as fat.

If you have persistently or repeatedly high blood glucose levels then more insulin is needed to bring blood glucose levels back to normal. This leads to chronically raised insulin levels, a condition called hyperinsulinaemia.

It is thought that your cells become resistant to the action of insulin in response to the high insulin levels [1].

There is also an argument for insulin resistance developing first. An increase in insulin levels occurs to overcome this resistance and maintain your normal response at the cellular level.

No matter the mechanism, the development of insulin resistance causes a deterioration in your metabolic health. This could cause you to have a variety of health problems such as:

significantly raised blood glucose (prediabetes)
increased subcutaneous and visceral fat (overweight or obesity)
raised blood pressure (hypertension)
raised cholesterol levels (hyperlipidaemia)

The development of any of these should be viewed as a huge warning sign. Having any combination of these can diagnose you as having metabolic syndrome.

Metabolic syndrome has been associated with and implicated in the development of many chronic diseases. This syndrome puts you at a higher risk for heart disease, dementia, cancer, diabetes, strokes, kidney disease and other health problems.

What are the risk factors for insulin resistance?

The most significant risk factors for developing insulin resistance are related to your lifestyle. Specifically, the quality of your diet, exercise habits, sleep and stress management [2].

Diet

It has been well established that if you consume more calories than you need, and have a sedentary physical activity, this leads to fat accumulation. The accumulation of fat, in particular visceral fat (fat stored around your internal organs), is believed to be a key step in the development of insulin resistance.

If you have a diet high in carbohydrates and fats then you have a higher risk of developing insulin resistance. Unfortunately, a high carbohydrate and fat diet is typical of modern western society’s diet.

Our diet is usually abundant in cheap, high sugar, energy-dense foods and drinks. It is becoming so prevalent and damaging that children and teenagers are now suffering from the consequences of poor metabolic health.

In the USA a child as young as 3 was diagnosed with type 2 diabetes [3] – a condition usually found in the middle-aged!

Exercise

Your level of physical activity is also a key risk factor [4]. Exercise habits such as aerobic exercise and resistance training are known to improve insulin sensitivity. By not including these activities in your life you are putting yourself at risk of developing insulin resistance.

Physical activity is not just limited to exercise, it also includes daily movement such as standing, walking, carrying etc. Nowadays work often involves prolonged sitting at a desk, which is now recognised as a risk factor for poor metabolic health.

If this prolonged sitting is not regularly interrupted with movement then it has been shown that you can increase your insulin resistance. This particular type of inactivity is thought to be so influential that there is doubt that even regular exercise can fully counter the damage!

Sleep

Sleep is vital for your body to recover from the demands of the day and to prepare for the next. Poor sleep duration and quality has been linked to the development of insulin resistance [5].

If you get too little sleep or it is of low quality, then this can limit both physical and cognitive recovery. It is thought that failure to fully recover is pro-inflammatory. Increased levels of inflammation in your body are known to be linked to insulin resistance.

It takes just one night of restricted sleep to trigger insulin resistance, demonstrating how vital getting a good night’s sleep is.

Stress

Another risk factor for you developing insulin resistance is stress [6]. Our ancestors relied on the body’s stress response to deal with threats such as predators. It was a short-lived but powerful fight-or-flight response for survival.

Our modern-day environment can elicit the same response. However, instead of it being a brief short-lived response to a brief short-lived threat, we maintain a prolonged fight or flight response to a never-ending “threat”.

This threat could be having a demanding boss, a bullying colleague, a high workload, financial worries, the commute to work, worry about your children, or the pressure of meeting social expectations as seen on social media platforms.

The list is endless and highly variable, but the result is the same – a chronically activated stress response. This leads to the chronic stimulation of your hypothalamic pituitary adrenal axis (a hormone system) causing you to have high levels of cortisol.

Cortisol is a hormone that directly interferes with the action of insulin, worsening insulin resistance. Without effectively managing the chronic stresses of your life, you risk the consequence of worsening metabolic health.

Other Causes

Other factors have been associated with insulin resistance. These include:

Being overweight/obese
Diets low in omega 3
Diets low in fibre
Vitamin D deficiency
Hormone disorders such as hypothyroidism and hyperthyroidism
Genetics
Increasing age
Medications such as steroids, antipsychotics, and certain blood pressure medications
Smoking

How common is insulin resistance?

The latest figures estimate that up to 46% of the population has insulin resistance [7]. However, getting an accurate number is difficult as it is not routinely assessed by healthcare professionals.

However, insulin resistance can be measured by recognising its metabolic consequences, i.e. metabolic syndrome.

Using this approach it can be seen that around 33% of adults have metabolic syndrome. It has been estimated that almost 90% of adults have some sort of metabolic impairment [8].

What are the features of insulin resistance?

Insulin resistance is often recognised by its metabolic consequences. These are dependent on how long you have had insulin resistance, the severity of your insulin resistance and your genetics.

Symptoms of insulin resistance

Symptoms are features of a health problem you can have that can’t be seen or shown in a medical test. Many symptoms could be linked to insulin resistance.

Physical Symptoms

having difficulty in losing weight
feeling tired all the time
difficulty gaining muscle mass
joint/muscle aches and pains

Cognitive Symptoms

poor concentration
brain fog
poor memory
poor decision making

Emotional Symptoms

anxiety
low mood
feeling hungry a lot of the time
sugar cravings

The signs of insulin resistance

Signs are features of a health problem that can be seen or can be shown in a medical test. There is a wide range of conditions that are directly caused, or very strongly influenced, by insulin resistance. No system in your body escapes its negative influence.

Cardiovascular

Hypertension (high blood pressure)
Heart disease

Neurological

Stroke
Dementia
Peripheral neuropathy (damaged nerves in hands and feet)

Endocrine

Raised body mass index (being overweight or obese)
Prediabetes
Type 2 diabetes

Renal

Kidney disease

Hepatic

Non-alcoholic fatty liver disease

Reproductive

Polycystic Ovarian Syndrome
Infertility
Erectile dysfunction

Dermatological

Acanthosis nigricans (velvety brown patches)
Skin tags

Nutritional

Hyperlipidaemia (high levels of blood lipids)

Cancer

Colorectal cancer [9]
Pancreatic cancer
Endometrial cancer
Breast cancer
Prostate cancer

How do you know if you have insulin resistance?

The gold standard measurement of insulin resistance

In medical science research, the gold standard for measuring insulin resistance is the “hyperinsulinaemic-euglycaemic glucose clamp technique”.

This is where you are infused with constant insulin whilst also being infused with increasing rates of a glucose solution (20% dextrose). The rate at which dextrose is infused to achieve a steady level of blood glucose is used to calculate your exact level of insulin resistance.

Surrogate markers of insulin resistance

Unfortunately, this clamping technique is not clinically practical so a host of surrogate markers for insulin resistance have been developed.

These different markers are calculations that use the results of your blood tests for fasting glucose, fasting insulin and triglycerides. For example, HOMA-IR is a popular method to indirectly measure insulin resistance using fasting glucose and insulin results.

Unfortunately, many healthcare professionals do not routinely measure your fasting insulin levels. This means you would not be able to use the HOMA-IR to determine your level of insulin resistance.

Blood lipids

However, your blood lipid levels are routinely measured. These results can be used to give an indirect measure of insulin resistance instead.

The triglyceride/HDL ratio is correlated with insulin resistance, with a ratio equal to or greater than 2.75 strongly associated with insulin resistance [10].

Continuous Glucose Monitor

A Continuous Glucose Monitor (CGM) is an increasingly accessible tool to detect insulin resistance. A CGM continuously measures blood glucose levels in real time.

If you use one of these devices you can see how your body responds to the ingestion of foods. It provides great insight into your carbohydrate tolerance and shows your level of insulin resistance.

The CGM provides data about your baseline blood glucose level, how high it spikes after eating food, and how long it takes to return to baseline. Using this data you can see the impact of your insulin resistance in real-time.

CGMs are powerful tools to enable behaviour change by encouraging you to modify the volume and the types of food to improve your insulin resistance over time.

Metabolic Syndrome

Another way for you to diagnose insulin resistance is by the presence of certain signs of its metabolic consequences.

Metabolic Syndrome (MetS) is a collection of those signs that are strongly associated with insulin resistance. If you meet three or more of the below criteria then you have metabolic syndrome:

Waist circumference: >40inches (102cm)
Raised triglycerides: >150mg/dl (1.695mmol/L)
Low HDL-C: <40mg/dl (1.04mmol/L)
High blood pressure: >130/85mmHg
High fasting blood glucose: >110mg/dl (6.1mmol/L)

Having MetS almost definitely means that you have insulin resistance. Waiting until you meet the MetS criteria before taking action is not ideal. Having any one of these features should trigger you to take action.

Waist-to-height ratio

A rather simple but powerful way to determine if you’re likely to have insulin resistance or not is a tape measure. Measure your waist circumference and your height to get your waist-to-height ratio. Having a ratio greater than 0.5 indicates that you are more likely to have insulin resistance.

How to treat insulin resistance?

As discussed earlier many different factors are driving the development of insulin resistance, but the main cause is your lifestyle.

To effectively prevent or reverse insulin resistance you will need a personalised strategy that addresses all its causes.

Your plan will need to incorporate nutrition, exercise, sleep, stress management, supplements and medication.

Nutrition

There are a variety of diets that are effective in reversing insulin resistance [11, 12, 13, 14, 15]. Particularly effective interventions are:

calorie restriction – reducing daily maintenance calories by at least 10%
high protein diet – a diet with at least 30% of calories coming from protein
low carbohydrate diet – a diet with about 20% of calories coming from carbohydrates
low glycaemic index diet – a diet with carbohydrates coming from foods that are low (<70) on the Glycaemic Index (a type of rating based on the rise in blood glucose a food causes relative to the rise found when consuming pure sugar)
the ketogenic diet – a diet with less than 55g (<10% of calories) of carbohydrates per day

No matter what approach you use, it is important to consider the quality of the foods you eat. It is best to avoid processed foods as they typically contain highly refined carbohydrates, saturated fats or high amounts of fructose. These are all known to increase insulin resistance.

It is also advantageous to have a diet high in fibre as it aids satiety and blunts the spike in your blood glucose after eating. Both of which can help improve your insulin sensitivity.

Fasting

Another approach is simply not to eat for periods of time. This strategy is called intermittent fasting [16].

There are a variety of different ways you can do intermittent fasting. For example:

the 5:2 diet – eat a normal, healthy diet for 5 days and fast for 2 days.
16:8 time-restricted feeding – eat a normal, healthy diet within the 8-hour window only. Spend 16 hours fasting.
prolonged fasting for up to 7+ days.

The effects you’d get from fasting would be similar to calorie restriction. However, it is also thought that fasting improves fat loss, the clearing of dysfunctional cells and proteins (autophagy), as well as improves insulin sensitivity in different ways than calorie restriction.