How Does Diabetes Affect the Heart and Cardiovascular System

Dr Jedha, Host

Hello wonderful people and welcome back to Type 2 Diabetes Talk. Today, we’re talking about an important and often overlooked connection: diabetes and heart health.

01:16

As a person living with type 2 diabetes or prediabetes, you’ve probably heard that you’re at greater risk of heart disease. And it certainly is true, people with diabetes are 2 to 4 times more likely to develop cardiovascular disease. When we think about that, it’s a staggering statistic, and it highlights what we talked about in episode 60 on why blood sugar is so important. And one of those primary reasons is that keeping blood sugar in a healthy range, is about protecting your heart and your whole body.

Before we dive in, I have something to share with our members, a fantastic new resource available to you now inside the members site under guides or from your Dash, and that is a brand-new Healthmap on Lowering Cholesterol. This Lowering Cholesterol Healthmap gives you a step-by-step action plan on tackling cholesterol, with checklists, food lists, and essentially what to do and what to focus on each step of the way to achieve balanced cholesterol levels. So head to the members site and check out that new Healthmap on Lowering Cholesterol.

Right, back to the topic of today: diabetes and heart health.

Let’s start by zooming out a little. Diabetes doesn’t just affect blood sugar—it’s a systemic condition that affects your entire body. One of the most vulnerable systems is your cardiovascular system: your heart and blood vessels, because as we know, blood travels throughout our body, pumped by our heart throughout the bodies blood vessels and arteries.

When blood sugar levels stay high over time, it can cause damage to the delicate lining of your blood vessels. This damage sets the stage for a range of complications, like hardened arteries, high blood pressure, and poor circulation. That’s why people with diabetes are at a higher risk for heart attacks, strokes, and other cardiovascular issues.

It’s important to remember that the heart and blood vessels work as a team. When one part of the system is affected, the rest can’t function at its best. So, keeping your heart healthy isn’t just a good idea—it’s a key part of looking after your diabetes and taking care of yourself.

For you, understanding the biological connection between diabetes and cardiovascular disease is very important because it lays the foundation for why managing your blood sugar is about so much more than just numbers, emphasizing what we covered in episode 60.

04:12

Essentially, it is high blood sugar that causes complications like heart disease and issues with the cardiovascular system. Over time, this excess sugar damages the lining of your blood vessels, setting the stage for complications like hardened arteries and decreased blood flow.

This damage, known as endothelial dysfunction, makes it easier for fatty plaques to form in your arteries, which can eventually lead to heart attacks, strokes, or poor circulation. While blood sugar is a key focus in diabetes management, its ripple effects on your cardiovascular system are just as critical to understand, especially if your levels are higher than they should be. Remember, it’s the high blood sugar levels or high A1c levels that causes damage to the vessels.

High blood sugar doesn’t just damage blood vessels directly, it also creates a cascade of inflammation throughout your body. Chronic inflammation is like having a fire smoldering in the background, quietly causing damage through your system over time. It plays a key role in the development of atherosclerosis, or the hardening of the arteries, which is a major driver of cardiovascular disease.

Another factor is oxidative stress, which occurs when your body has more harmful free radicals than it can neutralize. This imbalance can accelerate the damage to your blood vessels and contribute to the formation of dangerous clots. Think of it like rust forming on a car—it weakens the structure over time.

Diabetes rarely travels alone. It often brings along high blood pressure and abnormal cholesterol levels, creating a trilogy of issues. High blood pressure forces your heart to work harder, and this strain can weaken the heart muscle over time. Cholesterol imbalances, like high levels of LDL cholesterol and low levels of HDL cholesterol can lead to more plaque buildup in your arteries. Triglycerides, another type of blood fat, are also worth mentioning. People with diabetes often have elevated triglyceride levels, which can worsen the risk of cardiovascular disease. In fact, high triglyceride levels are highly associated with heart disease, not just high cholesterol or even high LDL cholesterol, as we covered about in episode 42.

07:44

So in the body, we’ve got several processes occurring that lead to increased risk of cardiovascular disease, and they all begin with higher than normal blood glucose levels. But there’s also another silent player here and that’s high insulin levels or hyperinsulinemia and insulin resistance, which is central to the development of pre and T2Diabetes, and many health conditions.

Insulin resistance doesn’t just affect blood sugar—it plays a central role in the development of cardiovascular disease. In fact, some researchers now suggest that heart disease itself could be viewed as insulin resistance of the heart and blood vessels. Here’s why this connection is so important.

Insulin resistance largely contributes to that state of chronic low-grade inflammation that occurs throughout the body. When insulin resistance is present, the body struggles to process fats effectively. This is what drives elevated triglycerides, low HDL (‘good cholesterol’), and an increase in small, dense LDL particles—the altered cholesterol we commonly see in diabetes. These lipid changes accelerate the buildup of plaque in arteries.

Insulin resistance is linked to high blood pressure. It increases sodium retention and activates the sympathetic nervous system, both of which raise blood pressure. Over time, the combination of stiff arteries and high pressure places additional strain on the heart.

The heart itself can become resistant to insulin, which affects its ability to efficiently use glucose for energy. This can lead to conditions like heart failure, where the heart struggles to pump blood effectively. Researchers are exploring how this ‘cardiac insulin resistance’ may be a critical factor in the progression of cardiovascular disease in people with diabetes.

On the continuum toward the development of heart disease lies the central issues of high blood sugar levels, high insulin levels and insulin resistance. The combination of these factors leads to increased inflammation in the body, oxidative stress, advanced glycation end products, affects nitric oxide bioavailability, mitrochondrial function, the sympathetic nervous system, and so many other intricate processes, none of which we can see of course and that’s all very technical. But the point is, it truly is amazing how everything is connected and while we cannot see inside our bodies, there is always a lot going on.

By understanding these biological processes or at least having some knowledge about them and considering them, well, you can see why keeping blood sugar levels in check is so vital—for avoiding diabetes complications and for protecting your heart and all those amazingly intricate processed occurring throughout the cells of the body.

11:16

In terms of the specific cardiovascular complications that are more common in people with diabetes, these include coronary artery disease, which occurs when the arteries supplying blood to your heart become narrowed or blocked due to plaque buildup. Heart failure, where the heart can’t pump blood as effectively as it should. Diabetes can contribute to this condition by damaging the heart muscle, a condition known as diabetic cardiomyopathy. High blood sugar levels in diabetes doesn’t just affect the arteries near your heart, it impacts blood flow throughout your body. This is known as peripheral artery disease, when blood flow to your limbs is reduced, often causing pain or cramping in the legs during walking, or loss of sensation. Then there’s stroke, which occurs when blood flow to the brain is interrupted.

These complications might sound daunting, but the good news is they’re not inevitable. You can dramatically lower your chances of developing these issues by being proactive, lowering blood sugar levels into the healthy range and taking good care of your health.

12:55

Now that we’ve explored how diabetes impacts the cardiovascular system, let’s shift our focus to what you can do to protect your heart.

If high blood sugar levels is the leading cause of these spiraling effects, then it make sense that blood sugar managagement is fundamental. Managing blood sugar is the foundation for protecting your heart. High blood sugar levels directly damage blood vessels, as we’ve discussed, but they also drive insulin resistance, inflammation, and a cascade of metabolic imbalances that affect your cardiovascular system.

Keeping your blood sugar and A1c levels in the healthy range, or as close to the normal healthy range as possible, is very important. It reduces stress on your blood vessels and prevents long-term complications.

One of the most effective ways to lower blood sugar and reduce cardiovascular risk is through your diet and nutrition. Focusing on lower carb, nutrient-dense foods can help reduce blood sugar spikes, improve insulin sensitivity, and lower triglycerides. Opt for non-starchy vegetables, healthy fats, and protein as your meal staples. Cut back on ultra-processed foods, added sugars, and refined grains, which contribute to inflammation and high triglycerides. I would highly recommend going back to listen to episode 6 on how to eat to treat diabetes, and also episode 41 on how to eat to beat inflammation. Both of these episodes will help you set some solid foundations, and in particular, episode 41 covers anti-inflammatory foods and anti-inflammatory supplements like Magnesium and turmeric. In fact, episode 48 on magnesium is a good one to listen to as well, since magnesium is an essential mineral for heart health and diabetes and people with pre and T2diabetes are often deficient or insufficient. Certainly, your diet and nutrition are key tools in taking care of your diabetes and your heart health.

Regular physical activity is another powerful tool for heart health and blood sugar management. Aim for at least 150 minutes of moderate exercise per week, like brisk walking, swimming, or cycling. Resistance training a couple of times a week helps build muscle, which improves your body’s ability to use insulin efficiently. Physical activity also lowers blood pressure and raises HDL cholesterol (the ‘good’ cholesterol), giving your heart extra protection.

Stress and poor sleep are often overlooked contributors to cardiovascular disease. Chronic stress raises cortisol levels, which can worsen blood sugar control and increase blood pressure. Similarly, poor-quality sleep can lead to higher insulin resistance and inflammation. In fact, we don’t realize just how much these factors influence not just our cardiovascular health, but many aspects of our health. According to research, 65% of people don’t get enough sleep, so try prioritizing 7-9 hours of quality sleep each night to help your body recover and regulate blood sugar levels. If you’re getting less than 7 hours, you’ve got room for improvement. And being proactive to incorporate stress-reducing activities like deep breathing, yoga, or simply taking time to unwind, this is really important to do on a regular basis.

Most of this just comes down to the basics of what we need to do to take care of ourselves and when we do these things consistently, we make a lot of progress in optimizing our health, feeling our best and taking care of our heart health.

17:15

Three other important aspects to consider are blood pressure, cholesterol, and weight and the insulin resistance connection. We explored the insulin resistance diabetes connection in detail in episode 26. The sheer fact is that the presence of insulin resistance drives a change in these aspects of health. That’s why many people with pre or T2diabetes also struggle with high blood pressure, abnormal cholesterol levels, and excess weight, all of which are major contributors to cardiovascular disease. While these are often treated as separate issues, they are deeply tied to insulin resistance and an altered metabolism, which is essentially what’s occurring in both pre and T2diabetes.

But here’s the thing: focus on improving your blood sugar and A1c levels and following a quality nutrition plan such as we recommend and this usually addresses this trilogy of issues.

High blood sugar and insulin levels and insulin resistance lead to sodium retention in the kidneys, causing high blood pressure. Of course, high blood sugar is not good as it can lead to stiffness in blood vessels and increased pressure that harms vessels. As you improve your blood sugar control, most people see improvements in blood pressure without needing additional interventions.

Insulin resistance drives an imbalance in lipids, leading to high triglycerides and low HDL cholesterol. Reducing blood sugar and insulin levels can help bring these markers back into a healthier range.

Excess weight, especially around the abdomen, is often a result of insulin resistance – the combination of high blood sugar and high insulin levels. When you lower blood sugar and improve insulin sensitivity, weight loss frequently follows, reducing strain on your heart.

The key takeaway here is that by focusing on managing your blood sugar first, you can bring these related factors into balance naturally. It’s a holistic approach that benefits not just your heart, but your entire metabolic health.

19:51

As we wrap up today, I hope you’re feeling more equipped to understand and address the connection between diabetes and your heart health. What we’ve covered shows how interconnected everything in your body truly is, your blood sugar, your insulin levels, your blood pressure, cholesterol, and even the strength of your heart.

The most empowering part of this conversation is that so much is within your control. By focusing on managing your blood sugar, you’re not just protecting yourself from the complications of diabetes, you’re taking care of your heart, your metabolism, and your overall health. Small, consistent actions you take every day, like choosing nourishing foods, staying active, and prioritizing rest, can create powerful ripple effects throughout your entire life.

Before closing, just to mention again for our members, the new Healthmap on Lowering Cholesterol, which is now available for you inside the members site under guides or from your dash. Whether you’re dealing with high LDL, low HDL, or elevated triglycerides, this guide walks you through practical strategies that tie directly into what we’ve discussed today and is designed to help you easily navigate the process to rebalancing your cholesterol levels, naturally. So after the episode, don’t forget to login to the members site to explore this invaluable Healthmap. If you’re not a member yet and want access to tools like this, please head over to our website and join us.

Well, that’s all from me today. Thanks for joining and see you next week.

Dr Jedha, over and out.