Doctors Reveal a ‘Main Culprit’ for Heart Disease

Looking at the metabolic roots of heart disease reveals why diabetics are at such high risk

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High blood cholesterol has been a central focus in cardiovascular disease for decades. However, doctors are now challenging this emphasis, proposing that it may have caused health practitioners to overlook a critical culprit: insulin resistance.

Insulin Resistance Is Cause for Concern

Dr. Robert DuBroff, a cardiologist and professor from the University of New Mexico, had a patient who suffered multiple cardiovascular events. The patient underwent coronary artery bypass three times and had been treated aggressively with statin medications, although his cardiovascular events continued.

Dr. DuBroff noticed that his patient’s blood sugar was borderline prediabetic and that he was overweight. However, these risk factors weren’t addressed by previous doctors; once they were, the patient stopped having additional problems.

Insulin resistance is the leading cause of Type 2 diabetes and an indicator of metabolic health. One study found that more than 80 percent of Americans were metabolically unhealthy, with nearly half prediabetic.

Type 2 diabetics face at least a twofold risk of developing cardiovascular disease, and most die from cardiovascular events. However, this is often missed in the literature, professor Ian Givens, who specializes in nutrition at the University of Reading, told The Epoch Times.

“The certification of death says cardiovascular disease—doesn’t say diabetes, which is technically true because that is what they’ve eventually died from,” Mr. Givens said. However, this perspective overlooks crucial information: It was diabetes that led the person to die from heart disease.

What Is Insulin Resistance?

Insulin, a hormone released into the bloodstream when blood sugar rises after a meal or other sugar consumption, directs the body’s fat, liver, and muscle cells to absorb the blood sugar for energy metabolism or storage, restoring normal blood sugar levels.

Insulin resistance occurs when the body’s cells no longer respond to insulin and don’t absorb blood sugar. Then, the brain signals pancreatic beta cells to secrete more insulin to help, and over time, the body’s insulin resistance intensifies. Ultimately, the overworked beta cells deteriorate and die off and blood sugar gets out of control.

Insulin Resistance and Heart Disease

In an article published in The Pharmaceutical Journal, the official journal of the Royal Pharmaceutical Society, renowned Drs. Aseem Malhotra and Robert Lustig wrote that insulin resistance is the “main culprit” of heart disease.

Insulin resistance contributes to all of the major heart disease risk factors.

Atherosclerosis

Atherosclerosis involves the development of plaques within blood vessels and eventual cardiovascular events such as heart attacks.

The elevated insulin production that comes with insulin resistance results in chronically elevated insulin levels in the body, which promotes chronic inflammation. This impairs blood vessel linings and fosters atherosclerosis. Additionally, inflammation heightens platelet activation, increasing vulnerability to blood clotting.

High insulin also contributes to dyslipidemia—an imbalance in blood lipids, or fats. Dyslipidemia manifests as high blood triglycerides, low levels of high-density lipoprotein (HDL) cholesterol, and high levels of low-density lipoprotein (LDL) cholesterol, with insulin influencing all three components.

As a storage hormone, insulin tells the liver to package ingested calories into triglycerides, a type of fat, to be distributed across the body for storage, elevating blood triglyceride levels.

Insulin suppresses HDL particle formation, reducing the “good” HDL cholesterol. When insulin levels increase, proteins that break down HDL particles also increase, which can cause an increased clearance of HDL particles from the blood.

“The HDL particle’s job is to bring lipids from the body back to the liver,” where they will “be recycled,” according to Benjamin Bikman, who has a doctorate in bioenergetics and is a cell biology and physiology professor at Brigham Young University specializing in metabolic disease and the pathological effects of insulin.

“But the insulin doesn’t want energy to be returning.”

Hypertension

Insulin increases heart rate and blood pressure. One way it does that is by activating the sympathetic nervous system.

The sympathetic nervous system is responsible for activating the fight-or-flight response, usually during periods of stress. That stress can be psychological or physical. Insulin can trigger a similar reaction. During the fight-or-flight response, adrenaline and cortisol are released into the bloodstream, blood pressure rises, and the heart beats faster.

Apart from acting as a hormone for storage, insulin also promotes growth, which can cause the inner lining of the blood vessels to thicken, increasing blood pressure.

Obesity

Elevated insulin levels lead to the storage of consumed sugar as fat instead of promoting its immediate consumption for energy, according to Dr. Jason Fung, a nephrologist and metabolic expert. This is also why meals high in carbohydrates, triggering insulin spikes, often induce hunger more quickly.

Preventing Insulin Resistance

Reduce Refined and Starchy Carbohydrate Consumption

Insulin is uniquely sensitive to glucose, so cutting down on sugary and starchy foods can prevent spikes in blood glucose and insulin levels. Any food that’s sweet, crunchy, or comes in packaging is usually high in carbohydrates, Mr. Bikman said.

Complex carbohydrates such as vegetables, legumes, and low-glucose fruits primarily consist of dietary fiber and have a minimal effect on blood sugar levels and insulin resistance.

Consuming fat and simple carbohydrates together is worse than consuming only carbohydrates or only fat. Although fat is calorically dense, fat by itself does not trigger insulin. However, in the presence of sugar or starches, insulin levels rise and stay up longer, Mr. Bikman said. Studies show that foods that combine sugar and fat increase cravings, stimulating overeating.

Practice Fasting and Chew Thoroughly

During fasts, no food is ingested, meaning there is no rise in blood sugar or insulin.

Fasting promotes the breakdown of fat in fat cells for energy and improves insulin sensitivity, according to a 2021 review.

According to Mr. Bikman, insulin resistance usually starts in the fat cells.

Fat cells can also expand up to 20 times their original diameter to accommodate more energy. But when fat cells reach maximum size and insulin prompts the cell to continue growing, Mr. Bikman said, they become insulin resistant.

Breaking down fat in these fat stores frees up room, thereby improving insulin sensitivity.

Chewing food thoroughly also helps; eating too quickly can result in swift spikes in blood glucose, triggering a robust insulin response. It is also linked with poorer satiety, making one more likely to snack after a meal.

Sleep and Build Muscle

Adequate sleep prevents stress and inflammation, which contribute to elevated blood glucose levels and insulin resistance.

Muscles are the primary consumers of glucose, using up to 80 percent of ingested glucose daily. If one maintains sugar intake while muscle mass decreases, excess sugar can’t be entirely burned and gets stored as fat.

Resistance training is the most effective exercise for increasing muscle mass, as suggested by David Stensel from Loughborough University, a specialist in exercise metabolism. He also recommends combining aerobic exercises with resistance exercises. Aerobic exercises are continuous, allowing people to engage in them for longer.

Aerobic and resistance training stimulate the release of growth hormones, which promote muscle development and boost metabolic rates.