If you currently have a health issue that has been bothering you for quite some time, there’s a high chance it is related to insulin resistance. Insulin resistance is a condition that is estimated to affect approximately one third of people in the UK, yet many don’t know they have it. Why is it so common and what can we do it make it more on people’s radar so that we prevent many diseases associated with it.
At the annual meeting of the European Association for the Study of Diabetes (EASD) held in Madrid last fall, insulin resistance was announced to be linked to more than 30 diseases, as well as risk of earlier death in women.
At the annual meeting of the European Association for the Study of Diabetes (EASD) held in Madrid last fall, insulin resistance was announced to be linked to more than 30 diseases, as well as risk of earlier death in women.
What makes insulin resistance so prevalent?
Since about early 2000s public health experts have known that insulin resistance is mainly associated with having a higher risk diabetes type 2 and several cardiovascular diseases, such as hypertension, high cholesterol and heart disease. The metabolic health experts at the EASD conference in Madrid shared their evidence that insulin resistance is linked to more than 31 health conditions and is a cause for a wider range of health issues than previously thought, such as sleep disorders, mood disorders, mental health conditions, Parkinson’s, eczema, gout and many other.
What is insulin resistance?
Insulin resistance is a chronic condition which occurs when the body’s cells do not adequately respond to circulating insulin. Insulin is secreted in response to eating specific foods and is responsible for the uptake of glucose into cells, thus insulin resistance often results in progressively increasing blood glucose levels, which leads to elevated risks of prediabetes and diabetes type 2. Insulin resistance is considered part of the metabolic syndrome diseases, which include obesity, cardiovascular diseases (CVD), hypertension, non-alcoholic fatty liver disease, hypercholesterolemia and polycystic ovary syndrome (PCOS).
All tissues that have insulin receptors can become insulin resistant, however, there are tissues that primarily drive insulin resistance, these are the liver, skeletal muscle, and fat tissue. While insulin resistance inhibits glucose being uptaken into these cells, the results of this is the increase of glucose in the bloodstream and also the production of beta-cells (in the pancreas), which further drives the development of high insulin levels or hyperinsulinemia. Hyperinsulinemia is a condition by which the pancreas makes more insulin in order to overcome the resistance, this leads to having higher levels of insulin in the bloodstream, repeating over and over the vicious cycle.
Before a person is diagnosed with diabetes type 2, it is estimated that he or she would have had insulin resistance for approximately 10 to 15 years prior. Can we spot it and prevent if from aggravating one’s health in advance?
All tissues that have insulin receptors can become insulin resistant, however, there are tissues that primarily drive insulin resistance, these are the liver, skeletal muscle, and fat tissue. While insulin resistance inhibits glucose being uptaken into these cells, the results of this is the increase of glucose in the bloodstream and also the production of beta-cells (in the pancreas), which further drives the development of high insulin levels or hyperinsulinemia. Hyperinsulinemia is a condition by which the pancreas makes more insulin in order to overcome the resistance, this leads to having higher levels of insulin in the bloodstream, repeating over and over the vicious cycle.
Before a person is diagnosed with diabetes type 2, it is estimated that he or she would have had insulin resistance for approximately 10 to 15 years prior. Can we spot it and prevent if from aggravating one’s health in advance?
There are some telltale signs of insulin resistance:
- You often feel fatigued through the day, often for no obvious reason when waking up in the morning
- You crave sweet foods each day, throughout the day
- You may have recurring headaches
- You feel tired and sleepy after eating a carbohydrate-rich meal
- You have night sweats
- You have central belly fat
The new evidence that the scientists at the EASD conference presented to their colleagues was developed from the data of the UK Biobank. UK Biobank. UK Biobank holds genetic, medical and lifestyle information of approximately 500,000 people in the UK. This metabolic conditions study involved 231,033 women and 198,126 men, aged between 40 and 69 years. To measure the presence of insulin resistance and its relation to health outcomes, the researchers used the TyG index.
The TyG index is a metabolic index used more frequently now in the assessment of insulin resistance and presence of metabolic syndrome diseases. In many medical settings the HOMA-IR has been used to-date to detect if insulin resistance is present. HOMA-IR is the Homeostasis Model Assessment of Insulin Resistance looks at how well your body is able to react to insulin. It is calculated by multiplying fasting plasma insulin (FPI) levels by fasting plasma glucose (FPG) levels and then dividing the value by 22.5. But HOMA-IR is mostly able to determine insulin resistance and insulin sensitivity. By contrast, the TyG index is additionally considered to be able to assess the function of the pancreas and presence or absence of insulin resistance in a variety of body tissues. Put it simply, the TyG index is more robust in predicting if you will develop insulin-resistance conditions or not. By looking at the health conditions of the UK Biobank participants for 13 years, the researchers were able to link insulin resistance to the development of more than 31 diseases and warn that in women this condition was also associated with an increased risk of earlier death.
Here are some of the health conditions that we now know are linked with having insulin resistance:
Insulin resistance and sleep disorders
Sleep disorders and insulin resistance have a bidirectional relationship. There is growing evidence from both clinical and epidemiological studies suggesting that people who experience sleep disturbances and obstructive sleep apnea (OSA) tend to show higher incidence of insulin resistance. Disrupted sleep and poor sleep quality is now independently associated with metabolic abnormalities that occur in the metabolic syndrome diseases, including hypertension, high cholesterol and dyslipidemia, and an increased risk of diabetes 2. What it means in real life is that if you have had sleep disorders for a while, you may have developed a metabolic condition or indeed several; and the other way around is true - having sleep apnea puts you at a much higher risk of developing high blood pressure, heart disease and stroke.
How are these two linked? In a number of studies, when healthy adults undergo partial sleep restriction, they demonstrate changes in the glucose metabolism, which include decreased glucose tolerance and insulin sensitivity. These metabolic changes are explained by the neuroendocrine regulation of appetite by the hormones of hunger and satiety (ghrelin and leptin, respectively). During restriction of sleep, the levels of ghrelin - the hormone of hunger - are increased, and the levels of leptin - the hormone of satiety - are decreased, giving the person a double whammy effect of being unusually hungry and unable to stop eating when the hunger has been satisfied. Thus, a growing body of epidemiological research supports the association between shorter sleep, poor quality sleep and the higher risk for weight gain, obesity and diabetes type 2.
As the rates of obesity climbed up since the early 2000s, our sleep habits have changed too. Since the 1960s sleep trends across the adult population have shown a decreasing number of total hours of sleep. There were 22.3% of adults sleeping under 6 hours in 1985; in 1990 this percentage was 24.4; and in 2012 29.2% of adults were sleeping regularly under 6 hours per night (US data).
Obstructive sleep apnea and insulin resistance
Obstructive sleep apnea is another sleep disorder that is highly associated with insulin resistance. Research shows that OSA increases insulin resistance independently of obesity. In patients with obstructive sleep apnea, the HOMA-IR index is higher when compared to those without the sleep condition.
Obstructive sleep apnea is another sleep disorder that is highly associated with insulin resistance. Research shows that OSA increases insulin resistance independently of obesity. In patients with obstructive sleep apnea, the HOMA-IR index is higher when compared to those without the sleep condition.
In the Sleep Heart Health Study, the largest epidemiological study on sleep and metabolic regulation, researchers first assessed the presence of obstructive sleep apnea by a polysomnography test, and then measured glucose and insulin levels. When controlled for body mass index (BMI), waist circumference, ethnicity, sex and smoking habits, people with higher levels of sleep fragmentation episodes had significantly higher blood glucose levels.
Insulin resistance and mental health disorders
A study from Stanford University n 2021 showed that having insulin resistance doubles the risk of developing major depressive disorder. Major depressive disorder affects approximately one in 6 people in the UK, and is a condition characterised by the feelings of despair, apathy, unremitting sadness, lack of interest in food and sleep disruptions. The team of Stanford researchers analysed data from 601 men and women as part of the ongoing longitudinal study on depression in the Netherlands. At the time of their enrolment in the study, people reported as being never affected by depression or anxiety. The researchers used three measures of estimating insulin resistance: fasting blood glucose levels, waist circumference and the ratio of triglycerides to HDL (cholesterol markers). They discovered that a moderate increase in insulin resistance, as measured by the triglyceride-to-HDL ratio, was associated with an 89% increase in the rate of new cases of major depressive disorder. The other two measures also showed a positive association of developing major depressive disorder in the 9-year of tracking the participants’ health.
A study on mice who were fed an obesogenic diet (with 10% of the daily food intake coming from sucrose-sweetened water) showed a link between anxiety and insulin resistance. When the rodents got administered the diet, their glucose sensitivity changed nearly from day one. From the early stages of glucose intolerance animals started having anxiety-like behaviours. The researchers concluded that glucose intolerance alone irrespective of obesity or diabetes 2 can elicit anxiety.
Insulin resistance and neurodegenerative disease
Alzheimer’s is often termed diabetes type 3, and it is an accepted fact that people with diabetes type 2 have a higher risk of developing Alzheimer’s disease. According to Alzheimer’s Disease International, the incidence of dementia is likely to reach 150 million worldwide by year 2050, with Alzheimer’s being in the lead of cases. Alzheimer’s is characterised by the early onset of tau protein accumulation and amyloid-beta plaque formation, both leading to later neuronal dysfunction.
There are several potential explanations how insulin resistance is linked to an increased risk of Alzheimer’s. One reason may be that in diabetes there’s reduced blood flow to the brain due to the damage in the blood vessels. Thus, data shows there is a progressive loss of neurons in the hippocampus resulting in impaired synaptic transmission.
A meta-analysis of 144 prospective studies on the relationship between diabetes type 2 and Alzheimer’s found a nearly 2-fold increased risk of cognitive disorders (such as cognitive impairment and dementia) in people diagnosed with diabetes 2.
Another potential reason for the links between Alzheimer’s and insulin resistance, is that having elevated blood sugar levels for a prolonged period of time one can have damage to various organs, including the brain. Insulin receptors are widely distributed throughout the brain, they are concentrated particularly in the regions crucial for memory, learning, and cognitive functions, such as the hippocampus, cerebral cortex, and hypothalamus. Research has shown that more than a decade before the onset of Alzheimer’s symptoms in patients symptoms, there is a decline in brain glucose metabolism.
Interestingly, metformin, the commonly prescribed medicine for managing diabetes 2, does not produce improvements in the brain functioning or changes in the cognitive abilities of patients.
Are you at risk?
Insulin resistance is a population-wide danger, especially since it goes undiagnosed for a long time. If you think you may have it, first check your HbA1c levels (this is glycated haemoglobin) and also do fasting insulin to be sure.
I have developed a comprehensive diet plan for those wishing to keep their blood sugar levels balanced and for those who may already have insulin resistance. The guide gives you the list of foods that will promote insulin-glucose levels, thus better avoiding, and the foods that are healthy to eat to keep blood sugar regulated. The guide includes recipes for breakfasts, lunches and dinners for a whole week, as well as exercise guide. See my Reverse Insulin Resistance Diet Plan here.
Keeping your blood sugar levels regulated is perhaps the most important thing you could do for your health, as you have seen so many of modern day conditions are linked with having insulin resistance. It is double important to regulate your blood sugar levels if you are age 45, as the risks of having it increase with age.
Let me know if you know about insulin resistance, perhaps you’ve been able to reverse it?
Keep healthy, stay joyful!
Love, Katya
Keep healthy, stay joyful!
Love, Katya