How does diabetes affect the heart? Over time, high blood sugar can damage the blood vessels that supply the heart and the nerves that control it. The CDC says people with diabetes have twice the risk of heart disease, and the American Diabetes Association (ADA) says cardiovascular disease is the number one cause of death in people with diabetes. Managing blood sugar, blood pressure, and cholesterol lowers that risk.
Key takeaways
- High blood sugar can damage the blood vessels and nerves that control the heart, according to NIDDK.
- CDC says people with diabetes have twice the risk of heart disease, and the risk rises the longer someone has diabetes.
- The three main heart problems linked to diabetes are coronary artery disease, heart failure, and heart rhythm or heart-rate problems.
- People with diabetes-related nerve damage may not feel chest pain during a heart attack, NIDDK says.
- Managing the ABCs (A1C, blood pressure, cholesterol) and not smoking is the core of heart protection for people with diabetes.
How Diabetes Affects the Heart: The Short Answer
- Blood vessels: high blood sugar can damage artery walls, which makes it easier for cholesterol plaque to build up and narrow the arteries that feed the heart.
- Heart muscle: diabetes is a risk factor for heart failure, a condition in which the heart cannot pump blood as well as the body needs.
- Heart nerves: nerve damage from diabetes can change how the heart rate responds to activity and position, and can blunt the chest pain that normally warns of a heart attack.
- Risk partners: high blood pressure, high LDL cholesterol, high triglycerides, smoking, and extra belly fat often travel with type 2 diabetes and add to heart risk.
Why Diabetes Raises Heart Risk
NIDDK says high blood glucose from diabetes can damage blood vessels and the nerves that control the heart and blood vessels, and that over time this damage can lead to heart disease. NIDDK also says people with diabetes tend to develop heart disease at a younger age, and that adults with diabetes are nearly twice as likely to have heart disease or stroke as adults without diabetes.
According to the CDC's "Diabetes and Your Heart" page, people with diabetes have twice the risk for heart disease, and the longer you have diabetes, the higher that risk. The ADA's Standards of Care in Diabetes—2026 say atherosclerotic cardiovascular disease is the leading cause of illness and death in people with diabetes, and that diabetes itself adds risk independent of other factors.
Blood sugar is only part of the picture. The American Heart Association (AHA) says diabetes greatly increases heart disease and stroke risk even when glucose levels are under control, because people with type 2 diabetes often also have high blood pressure, unhealthy cholesterol levels, obesity, and low physical activity. That is why heart protection with diabetes covers more than one number.
The Main Heart Problems Linked to Diabetes
| Heart problem | What happens | Common signs | Where to read more |
|---|---|---|---|
| Coronary artery disease | Plaque narrows the arteries that feed the heart | Chest pressure, shortness of breath, or no symptoms at all | This guide |
| Heart attack | A blocked artery cuts off blood to part of the heart muscle | Chest discomfort, arm, jaw, or back pain, sweating, nausea, unusual tiredness | Silent heart attacks and diabetes |
| Heart failure | The heart cannot pump enough blood for the body's needs | Shortness of breath, swelling in feet and legs, fatigue | Diabetes and heart failure |
| Heart rate and rhythm problems | Nerve damage or heart changes affect heart rate and rhythm | Fast resting heart rate, light-headedness when standing | Diabetes and high heart rate |
| Stroke and peripheral artery disease | The same plaque process affects the brain and leg arteries | Sudden one-sided weakness, or leg pain when walking | Diabetes and stroke |
Coronary artery disease
The CDC says the most common type of heart disease is coronary artery disease, caused by plaque building up in the blood vessels that supply the heart. Plaque narrows the arteries and decreases blood flow. Reduced blood flow to the heart can cause a heart attack. The CDC adds that hardening of the arteries can happen in the legs and feet too (peripheral arterial disease, or PAD), and that PAD is often the first sign that a person with diabetes has cardiovascular disease.
Heart failure
The CDC says people with diabetes are more likely to have heart failure, which means the heart cannot pump blood well. The ADA's 2026 Standards say heart failure is at least twofold more common in people with diabetes. Our guide to whether diabetes causes heart failure explains the warning signs and the blood test ADA suggests doctors consider.
Heart nerves
Autonomic neuropathy is damage to the nerves that control internal organs. NIDDK says damage to the nerves that control heart rate and blood pressure can make them respond more slowly to changes in position, stress, activity, sleep, and breathing. You may feel light-headed when you stand up, or have a rapid heart rate. NIDDK says this nerve damage can also prevent you from feeling chest pain when your heart is not getting enough oxygen or when you are having a heart attack. See our guide to diabetic neuropathy for the other types.
What Adds to Heart Risk With Diabetes
NIDDK and CDC list factors that raise the chance of heart disease or stroke in people with diabetes:
- High blood pressure — makes the heart work harder and can damage artery walls. See whether diabetes causes high blood pressure.
- Abnormal cholesterol and triglycerides — high LDL cholesterol can form plaque on damaged artery walls. See how diabetes affects cholesterol.
- Smoking — NIDDK says both smoking and diabetes narrow blood vessels. See how smoking affects blood sugar.
- Extra belly fat — NIDDK says a waist over 40 inches for men or over 35 inches for women raises the chance of heart disease, even if you are not overweight.
- Chronic kidney disease — NIDDK says heart disease is closely linked with kidney disease, which affects about 40% of people with diabetes. See how diabetes affects the kidneys.
- Family history — NIDDK says that if one or more family members had a heart attack before age 50, your chance of heart disease is doubled.
- Low activity, a diet high in saturated fat, trans fat, and salt, and drinking too much alcohol — the CDC lists these as added risk factors.
How Doctors Check Your Heart
The CDC says your blood pressure, cholesterol levels, and weight help your doctor understand your overall heart risk. NIDDK says the tests used to monitor diabetes (A1C, blood pressure, and cholesterol) help your doctor decide whether more heart tests or a cardiologist referral are needed.
Tests the CDC names include:
- Electrocardiogram (ECG or EKG) — measures the heart's electrical activity.
- Echocardiogram (echo) — shows how thick the heart muscle is and how well the heart pumps.
- Exercise stress test — shows how the heart works when it is working hard.
The ADA's 2026 Standards say routine screening for coronary artery disease is not recommended for people without symptoms, as long as heart risk factors are being treated. The Standards say doctors should consider testing when there are signs or symptoms of heart or blood vessel disease, or an abnormal ECG. The same section suggests doctors consider a blood test called a natriuretic peptide (BNP or NT-proBNP) to look for early heart failure risk. Which tests fit you is a decision for your care team.
What Lowers Heart Risk With Diabetes
NIDDK says you can substantially lower your chances of a heart attack or stroke by managing your diabetes ABCs and not smoking:
- A — A1C: NIDDK says the A1C goal for many people with diabetes is below 7%, but your goal may differ.
- B — Blood pressure: the ADA's 2026 Standards set an on-treatment goal of below 130/80 mm Hg if it can be safely reached. NIDDK and CDC pages still list below 140/90. Ask your care team which goal applies to you; our guide to blood pressure targets for diabetics explains the difference.
- C — Cholesterol: ask what your numbers should be. See cholesterol targets for diabetics.
- S — Stop smoking: NIDDK says e-cigarettes are not a safe option either.
The CDC adds daily habits that support heart health: eating more vegetables, fruit, lean protein, and whole grains; fewer processed foods and sugary drinks; being physically active; aiming for a healthy weight; and managing stress. Our step-by-step guide to lowering heart disease risk with diabetes turns these into a weekly plan.
NIDDK also says medicines may be part of heart protection, including statins and certain diabetes medicines that have been shown to reduce heart risk in some people. Whether you take any of these, and which one, is a decision for your prescriber. Do not start or stop a medicine on your own.
When to Call 911
NIDDK says to call 911 right away for any of these heart attack warning signs:
- pain or pressure in the chest that lasts longer than a few minutes or goes away and comes back
- pain or discomfort in one or both arms or shoulders, or the back, neck, or jaw
- shortness of breath
- sweating or light-headedness
- indigestion or nausea
- feeling very tired
NIDDK says warning signs can differ between people, and that people with diabetes-related nerve damage may not notice any chest pain. If something feels wrong, call. Do not drive yourself.
Frequently Asked Questions
How does diabetes affect the heart?
NIDDK says high blood glucose can damage blood vessels and the nerves that control the heart and blood vessels, and that over time this damage can lead to heart disease. Diabetes also raises the risk of heart failure, and it often comes with high blood pressure and unhealthy cholesterol, which add to heart risk.
Are people with diabetes more likely to have heart disease?
Yes. The CDC says people with diabetes have twice the risk of heart disease, and NIDDK says adults with diabetes are nearly twice as likely to have heart disease or stroke. The ADA says cardiovascular disease is the number one cause of death in people with diabetes.
Can diabetes damage the heart even if blood sugar is controlled?
The American Heart Association says diabetes greatly increases the risk of heart disease and stroke even when glucose levels are under control, because high blood pressure, unhealthy cholesterol, obesity, and inactivity often come with type 2 diabetes. That is why blood pressure, cholesterol, and not smoking matter as much as A1C.
What heart tests do people with diabetes need?
The CDC says blood pressure, cholesterol, and weight help your doctor judge your heart risk, and names the ECG, echocardiogram, and exercise stress test as possible tests. The ADA's 2026 Standards do not recommend routine coronary screening without symptoms when risk factors are treated. Ask your care team which tests fit you.
Can you feel heart problems with diabetes?
Not always. NIDDK says nerve damage from diabetes can prevent you from feeling chest pain when your heart is not getting enough oxygen or during a heart attack. Shortness of breath, unusual tiredness, sweating, or nausea may be the only signs. Call 911 if you think you are having a heart attack.
What is the best way to protect your heart with diabetes?
NIDDK says managing your diabetes ABCs (A1C, blood pressure, and cholesterol) and not smoking can substantially lower your chances of a heart attack or stroke. The CDC adds healthy eating, regular physical activity, a healthy weight, and stress management. Ask your care team about your personal goals.
References
- Centers for Disease Control and Prevention. "Diabetes and Your Heart." Accessed October 2026.
- National Institute of Diabetes and Digestive and Kidney Diseases. "Diabetes, Heart Disease, & Stroke." Accessed October 2026.
- National Institute of Diabetes and Digestive and Kidney Diseases. "Autonomic Neuropathy." Accessed October 2026.
- American Diabetes Association. "Cardiovascular Disease." Accessed October 2026.
- American Diabetes Association Professional Practice Committee for Diabetes. "10. Cardiovascular Disease and Risk Management: Standards of Care in Diabetes—2026." Diabetes Care. 2026;49(Suppl. 1):S216–S245.
- American Heart Association. "Cardiovascular Disease and Diabetes." Accessed October 2026.
Next Steps
Write down your latest A1C, blood pressure, and cholesterol numbers, and ask your care team what your goal is for each. Learn the heart attack warning signs, including the quieter ones.
For adults with type 2 diabetes or prediabetes who want lifestyle education alongside clinical care, the Done With Diabetes™ program, a holistic approach to diabetes type 2, organizes daily learning about meals, movement, sleep, and stress. It does not diagnose or treat heart disease or diabetes, interpret test results, change medicines, or replace your care team.