Insulin Resistance: The Key To Chronic Disease
Why insulin resistance may the key risk factor for the diseases most likely to kill you
You are going to die from something.
The key to living longer is to delay the onset of the disease that is likely to kill you.
The leading causes of death worldwide are cardiovascular disease and cancer. They are the leading causes by a very large margin.
The priority then is to delay the ONSET of cardiovascular disease or cancer to later in life.
This is done by preventing or managing the risk factors that lead to these diseases.
The leading risk factors for adults over 50 years of age are clear.
High blood pressure
Smoking is an obvious risk factor for cardiovascular disease and cancer that requires no further explanation.
But let’s look at the other three factors.
Does this cluster of risk factors remind you of anything?
Answer: Metabolic Syndrome.
(Tweet Thread below on metabolic syndrome if you need a refresher)
Having metabolic syndrome significantly increases your risk of heart disease and certain cancers. This is why this cluster of risk factors is the leading set of risk factors for early death.
But what causes metabolic syndrome?
In short, insulin resistance.
So what is insulin resistance?
Insulin is a hormone released from your pancreas to move glucose from your bloodstream into your liver, muscle and fat cells to store it as glycogen.
Insulin resistance is when you need more insulin than normal to do the above task.
The end result is higher levels of circulating insulin.
For the most part, high insulin levels do not cause any symptoms and are usually elevated for years, possibly decades, before the appearance of any medical conditions or blood tests that are usually done.
Insulin resistance is present for 10 to 15 years before the appearance of type 2 diabetes.
This bears emphasising:
For these 10 to 15 years, a person’s glucose will be entirely normal.
There will be NO signs of any issue on traditional blood glucose or HBA1c blood tests.
Of all the silent killers.
This is the one to pay the most attention to.
Insulin levels can be measured with a simple blood test. The challenge is it is rarely done.
High cholesterol causes coronary artery disease.
But if cholesterol is the fire that causes coronary artery disease, insulin resistance is the equivalent of throwing gasoline on that fire.
Compared to those with low insulin levels (No insulin resistance) and low cholesterol levels as measured by APOB (The best measure of cholesterol), those with both high insulin and high cholesterol/APOB had a risk of heart disease that was 11 times higher.
High Cholesterol + High Insulin = Very Bad News
But to dispel any doubt, if you had normal insulin levels and high cholesterol, your risk was still 80% higher than if you had both normal insulin and cholesterol.
Cholesterol in the presence of high insulin levels leads to the formation of small dense cholesterol particles that are more likely to cross the artery wall and cause atherosclerosis to form.
Remember, type 2 diabetes is a state of very high insulin levels, which is why it is a risk factor for coronary artery disease, with the risk being ten times that of someone without diabetes.
Diseases Of Ageing
Conditions such as cancer, high blood pressure, diabetes and heart disease are often thought of as predictable ‘diseases of ageing’.
But maybe they are simply diseases of insulin resistance?
Worsening insulin resistance is associated with a higher risk of cancer, heart disease, high blood pressure and stroke.
Studies have shown that in healthy non-obese individuals followed from age 50, those with high insulin levels at baseline were most likely to be diagnosed with any of the above conditions mentioned.
Interestingly, the individuals with low insulin levels at baseline were not diagnosed with any of the above conditions over the approximately ten years of observation.
To be clear. Normal insulin levels are likely to be very protective against the premature onset of these conditions, but in isolation is not going to provide complete immunity from them.
Reversing Insulin Resistance
While the outlook for those with insulin resistance appears bleak, the amazing news is that high insulin levels and insulin resistance can be reversed.
You guessed it.
There are specific types of exercise that are likely to be far more effective at addressing insulin resistance, but even a single bout of exercise can improve insulin sensitivity by up to 40%.
This is likely why regular exercise is associated with a reduced likelihood of prematurely dying from ANY cause.
Reversing insulin resistance is also associated with weight loss, and the optimal approach is to combine the two strategies.
When it comes to delaying the onset of the chronic diseases that are most likely to kill you, insulin resistance is likely underlying most of them.
To be 100% clear, insulin resistance is likely not the CAUSAL factor for all of the conditions mentioned, but it is very likely to be a major accelerant.
If extending your life is a priority, then understanding if you have insulin resistance is a must.
If you have insulin resistance, and even if you don’t, exercise has to be a daily part of your life.
Measuring blood insulin levels can be a challenge but ask yourself if, from what you have read above whether overcoming that challenge is worth it.
I think it is.
The data makes it 100% clear that it is.
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