Beyond Diabetes: Insulin Resistance a Precursor to Cardiovascular Disease Functional medicine imparts new wisdom into how Insulin resistance affects heart health

Most of what we usually hear regarding insulin deals with medications you can take that lower your risk of developing type 2 diabetes, and less about the deleterious effects of the disease, or what blood sugar really is, and how our bodies use it for fuel. Insulin resistance also has been found to be a “major underlying abnormality driving cardiovascular disease” (National Institutes of Health, August 2000), including heart attack and stroke. Unfortunately, most patients don’t even fully understand the warning signs or the symptoms, as insulin resistance is considered a common health problem in the United States. The predominance of those who have insulin resistance—many times unbeknownst to them—is continually increasing.

What is Insulin Resistance?

Insulin resistance is a metabolic disorder characterized by extreme fatigue after meals, brain fog and similar slowing down of metabolism that leads to weight gain, high blood pressure, and lack of motivation. In a technical sense, the body doesn’t allow insulin into the cell, especially to brain cells, where glucose is the primary fuel. This isn’t something that happens suddenly—it’s a slow process caused by any of the factors listed below (primarily high-sugar and high-carb intake) as more insulin is needed by your body to keep your blood sugar at the right level. That said, it affects children in early, pre-pubescent childhood. Another misconception is that everyone with insulin resistance or elevated blood sugar is heavy or fat.

The inability to regulate blood sugar sets off an inflammatory cascade that leads to cardiovascular disease in a couple of different ways. One way this can happen is when insulin resistance alters a person’s systemic lipid metabolism, which then leads to high levels of triglycerides, small dense low-density lipoproteins, and low levels of high-density lipoprotein; this combination contributes to the formation of plaque in the arteries and vascular damage.

Another contributor to arterial plaque formation caused by insulin resistance is endothelial dysfunction, which is a type of coronary artery disease where the large blood vessels on the surface of the heart narrow instead of opening. Evidence of the fact that insulin resistance can directly lead to the formation of fatty plaque in arteries was borne out in the Insulin Resistance Atherosclerosis Study.

Hyperinsulinemia—when the amount of insulin in the blood is higher than normal—can lead to salt and water retention in the body, which in turn leads to hypertension, a condition that can cause heart failure, coronary artery disease, heart muscle thickening, and other cardiovascular diseases. Insulin resistance can also be at the root of obesity, high blood pressure, and high cholesterol—when all three are present, it’s called metabolic syndrome—which are all known to cause cardiovascular disease. Because insulin resistance can be at the root of these and so many other different types of cardiovascular issues, it’s considered a “multifaceted syndrome that increases significantly the risk for cardiovascular disease” (National Institutes of Health).

Risk Factors for Developing Insulin Resistance

There are a number of factors that can lead to insulin resistance, including:

  • high carbohydrate diet
  • sedentary lifestyle
  • diet high in sugars
  • trans-fats in the diet
  • obesity
  • smoking
  • hormonal disorders
  • poor sleep
  • certain prescription medications
  • out-of-balance gut microbiome
  • diet low in healthy fats
  • chronic stress
  • environmental toxins

These risk factors, among others, cause oxidative stress and damage insulin-making beta cells in the pancreas, as well as triggering insulin resistance. Hyperglycemia occurs when the pancreas can’t manufacture enough insulin, leading to oxidative stress, which then contributes to a number of health issues including vascular damage.

Conventional Approach vs. Functional Medicine Approach

Unfortunately, conventional medicine doesn’t usually monitor insulin resistance or take action until a person’s blood sugar numbers reach dangerous levels or they have a full-blown cardiac or diabetic event. The standard approach is to “watch” rising blood sugar levels, monitoring them periodically through fasting blood tests until a high-risk level is reached. However, insulin levels are not typically taken at all, yet they can rise before blood sugar, serving as an indication to take action. On the other hand, there are cases where blood sugar levels are normal but insulin levels are very high—these risky insulin levels are not usually found by convention medicine because doctors are not testing for them. The resulting cardiac event will then be treated, but attention may not be paid to the underlying cause of insulin resistance.

Standing by and watching a person’s health deteriorate until it reaches a crisis level is not and never has been the approach used in functional medicine. The loss of sensitivity to insulin is progressive and would be spotted by a functional medicine doctor through regular comprehensive lab tests that pick up the problem early in its development. If a patient already has insulin resistance, a case-specific plan can be put in place to pinpoint the areas where corrective action needs to be taken in order to reverse the condition—without dangerous medications.