If you or someone you love has been diagnosed with type 2 diabetes, you’ve probably heard that it puts you at greater risk for heart disease. But new research from The University of Sydney has uncovered something even more concerning: diabetes doesn’t just increase the risk – it changes the heart’s structure and energy systems at a microscopic level.
Let’s break down what this means, why it matters, and how you can protect your heart and boost your energy.
The Study: What Did Researchers Find?
The research team analysed human heart tissue from both transplant recipients and healthy donors. Their study, published in EMBO Molecular Medicine, revealed that type 2 diabetes causes distinct changes to heart cells and the heart muscle itself. These changes are especially pronounced in people with ischaemic cardiomyopathy—the most common cause of heart failure.
The key findings include:
- Diabetes disrupts the way heart cells produce and use energy.
- It alters the protein makeup of the heart muscle, affecting how well it contracts and handles calcium.
- It leads to a build-up of tough, fibrous tissue, making it harder for the heart to pump blood efficiently.
- Diabetes increases stress on mitochondria—the tiny “powerhouses” that provide energy to cells.
The Role of Mitochondria: Why Fatigue Is So Common
Mitochondria are often called the engines of our cells. They are the components of our cells that literally turn food into energy and power everything we do. In diabetes, mitochondrial function is impaired, especially in heart muscle cells. That means less energy is available for your heart to beat effectively, thereby making you more likely to experience fatigue.
This doesn’t just make you feel tired; mitochondrial dysfunction can contribute to muscle weakness, poor exercise tolerance, cognitive impairment and reduced heart function. Over time, if the heart can’t get enough energy, its structure changes, with more fibrous tissue and less of the flexibility it needs to work properly.
Insulin Resistance: The Invisible Culprit
Insulin resistance, a hallmark of type 2 diabetes, means your body’s cells don’t respond as well to insulin. Insulin helps move glucose from the bloodstream into cells. In the heart, less glucose transport into cell means that the heart becomes starved of the energy it needs, and the mitochondria are put under added stress as they try to compensate.
This combination of energy shortage causes mitochondrial stress which together trigger the development of tough, fibrous tissue within the muscle of the heart. This further decreases its ability to function and leads to a gradual decline towards eventual heart failure.
How Can You Protect Your Heart and Mitochondria?
Even though insulin resistance and diabetes can change your heart at a cellular level, there are practical steps you can take to shield your heart and mitochondria from further damage. Here are some key tips:
- Keep Blood Sugar Under Control: Managing your glucose levels helps prevent further insulin resistance and reduces stress on your heart cells. Chat with us about ways to do this.
- Stay Active: Regular exercise boosts mitochondrial function and helps your heart use energy more efficiently. Even brisk walking can make a difference.
- Eat a Heart-Healthy Diet: Focus on vegetables, lean proteins, and healthy fats like olive oil and nuts. Avoid processed foods, starchy carbohydrates and sugar.
- Don’t Ignore Fatigue: If you’re feeling unusually tired, there is usually an underlying reason. Fatigue can be a sign of underlying heart or metabolic problems.
- Monitor Heart Health: Get regular check-ups, including monitoring your blood pressure and ability to breath when exercising, especially if you have diabetes. These may be early symptoms of a decline in heart health and early detection is vital.
- Manage Stress: Chronic stress can worsen insulin resistance and impact heart health. Chat to us about a Heartmath evaluation.
- Stay Engaged with Your Care Team: Work with your doctor, nurse, and diabetes educator to tailor your treatment plan. Don’t be afraid to ask about new therapies or research findings.
Key Points:
This research shows that diabetes actively changes the heart’s structure and energy production at the molecular level. The good news is that this can be avoided by understanding these changes and taking proactive steps to avoid insulin resistance. This is a key factor in improving the long-term health of your entire body, so you age well and have a vibrant life and retirement.
Remember, small changes add up. With the right approach, you can continue to live well and keep your heart strong, even with diabetes.
Here is a link to the study (if you really want to geek out) – EMBO Mol Med (2025).
