Insulin resistance is emerging as a key player in cardiovascular disease. What can you do about it?
For decades, cholesterol has been vilified as the key factor driving heart attacks and strokes. While new drugs can drastically reduce LDL (bad) cholesterol, studies suggest that lives are not being saved by this approach. A paradigm shift is underway, and refined carbohydrates, sugar, and insulin resistance are emerging as key threats to heart health.
The role of insulin
Insulin is an essential hormone that escorts glucose (blood sugar) molecules from our circulation into body cells. Insulin-resistant cells can’t respond to the knock of this hormonal chaperone on their walls. In a futile attempt to knock more loudly, the pancreas produces more insulin, but the signal is not received. Blood glucose levels continue to rise, progressing over time to type 2 diabetes.
While serious, diabetes is not the only consequence of insulin resistance. Infertility, metabolic syndrome, polycystic ovarian syndrome, liver disease, and some cancers are all linked with disturbed insulin function. So is cardiovascular disease: People with diabetes are three times more likely to die of cardiovascular disease, and insulin resistance alone will double one’s risk.
Insulin resistance: three strikes to the heart
If insulin helps our bodies to function, why is too much of this hormone so harmful? High insulin levels deal three strikes to our bodies by
- causing direct cellular damage to the cardiovascular system
- prompting changes to blood vessels, which encourages plaque formation
- fueling cholesterol production and increasing blood pressure
What causes insulin resistance?
Insulin resistance is linked to obesity and a sedentary lifestyle. Sugar is also a suspect, but weight gain caused by high-sugar diets may be the true culprit. Men are at slightly higher risk owing to their tendency to deposit extra weight around their abdominal organs. Other contributors are sleep apnea, poor sleep quality, psychological stress, environmental pollutants, and possibly even artificial sweeteners. Inflammation may add fuel to the fire.
Cardiovascular disease is the leading cause of death in America and worldwide.
How is it targeted?
Simply addressing that list of factors will improve your body’s response to insulin (also called “insulin sensitivity”). In people who are obese or overweight, weight loss sensitizes tissues to the message of insulin, lowering blood sugar and insulin levels. If you have been prescribed a CPAP (continuous positive airway pressure) machine, wearing it nightly may improve your insulin response.
Effects of exercise
Studies continue to investigate the most insulin-sensitizing forms of exercise, but while the scientists sort it out, get moving in any way you like. Higher-intensity exercise is likely most beneficial, but simply breaking up inactive periods with intermittent movement will help.
Following a Mediterranean-style diet seems to improve insulin sensitivity while protecting the heart through lowering cholesterol, blood pressure, weight, and systemic inflammation. While questions remain about the benefits or risks of alcohol, dairy, and grains on this plan, a plant-heavy diet packed with fiber, nuts, and antioxidant-rich foods should support proper insulin function. Legumes like peas, lentils, and chickpeas are also important for your heart.
What about supplements?
Key supplements could be considered in combination with a targeted diet and exercise plan and with the guidance of a qualified health care practitioner.
Vitamin D insufficiency has been implicated in insulin resistance. A 2019 meta-analysis found that vitamin D and calcium improved insulin levels when taken in combination.
Berberine, a bright yellow compound found in plants like goldenseal, barberry, and Oregon grape, is another promising agent. In research involving people with metabolic syndrome, berberine improved insulin levels while reducing blood pressure, waist measurements, and triglycerides. In a study of people with diabetes, berberine increased insulin receptor expression, possibly explaining how it improves insulin sensitivity.
Another plant extract, curcumin, may act on inflammatory molecules to reduce insulin resistance.
Zinc may also lower insulin and blood sugar levels. People with prediabetes who took just 20 mg of zinc per day improved insulin measurements and cholesterol levels and were less likely to progress to diabetes. Ongoing research into myo-inositol and magnesium may reveal additional options for improving insulin management.
Supplements to consider
Doses may vary depending on the advice of your health care practitioner.
- Vitamin D and calcium – 2,000 IU and 1,000 mg per day, respectively
- Berberine – 500 mg, three times per day before meals
- Curcumin – 180 mg per day
- Zinc – 20 mg per day
- Myo-inositol – 4 g per day (in women with polycystic ovary syndrome)
- Magnesium – 250 mg per day