Diabetes makes you more likely to develop serious diseases

If you have diabetes, your body struggles to control blood sugar. Over time, high blood sugar damages blood vessels and nerves throughout your body. That damage opens the door to heart disease, kidney disease, stroke, and eye problems — even if you manage your diabetes well. The longer your blood sugar stays high, and the less controlled it is, the greater your risk.

The good news: you can slow or prevent many of these diseases by keeping your blood sugar as close to normal as possible, staying active, eating well, and taking your medications as prescribed. Catching these conditions early also makes a huge difference in how well you can manage them.

Key Takeaways

  • High blood sugar damages blood vessels and nerves, which is why people with diabetes face higher risk for heart disease, stroke, kidney disease, and eye problems.
  • Heart disease and stroke are the leading causes of death among people with diabetes, so managing blood pressure and cholesterol is as important as managing blood sugar.
  • Kidney disease often has no symptoms in early stages, so people with diabetes should have their kidney function checked at least once a year.
  • Eye damage from diabetes can lead to blindness, but regular eye exams and good blood sugar control can prevent or slow vision loss.
  • Nerve damage can cause pain, numbness, or loss of feeling, especially in the feet, which increases the risk of injury and infection.

Heart disease and stroke: the biggest threat

People with diabetes are two to four times more likely to have a heart attack or stroke than people without diabetes. High blood sugar damages the inner lining of blood vessels, making it easier for plaque to build up. Over time, those vessels narrow and harden, restricting blood flow to your heart and brain.

You can lower your risk by keeping your blood pressure below 130/80 mmHg (or the target your doctor sets), managing your cholesterol, not smoking, staying physically active, and eating a heart-healthy diet. Take any blood pressure or cholesterol medications your doctor prescribes, even if you feel fine — these drugs work silently to protect you.

Warning signs of a heart attack include chest pain or pressure, shortness of breath, nausea, and pain in your arm, jaw, or back. Signs of stroke include sudden weakness on one side of your body, trouble speaking, or vision changes. Call 911 when ready if you notice any of these.

Kidney disease: often silent until it's advanced

High blood sugar damages the tiny blood vessels in your kidneys that filter waste from your blood. Over time, your kidneys lose the ability to do their job, and waste builds up in your body. Early kidney disease usually has no symptoms — you feel fine even as your kidneys are being damaged.

The only way to catch kidney disease early is through blood and urine tests. Your doctor should check your kidney function (through a test called eGFR) and look for protein in your urine at least once a year. If kidney disease is caught early, medications and lifestyle changes can slow it down significantly.

If kidney disease progresses, you may eventually need dialysis (a machine that filters your blood) or a kidney transplant. That is why catching it early and controlling your blood sugar, blood pressure, and cholesterol matters so much.

Eye damage and vision loss

Diabetic retinopathy occurs when high blood sugar damages the blood vessels in the back of your eye. In early stages, you may not notice any symptoms — the damage is happening without you feeling it. As it progresses, you might see floaters, blurry vision, or dark spots. Without treatment, it can lead to blindness.

A dilated eye exam (where your eye doctor puts drops in your eyes to widen your pupils) is the only way to catch diabetic retinopathy early. You should have this exam at least once a year, and more often if your doctor recommends it. If retinopathy is found, laser treatment or injections can often stop it from getting worse.

People with diabetes are also more likely to develop cataracts (clouding of the lens) and glaucoma (increased pressure in the eye). Good blood sugar control and regular eye exams are your best protection against all three.

Nerve damage: pain, numbness, and injury risk

Diabetic neuropathy is nerve damage caused by high blood sugar. It most often affects the feet and legs, but can also affect your hands, arms, and other parts of your body. You might feel tingling, burning, or sharp pain — or you might feel nothing at all, which is actually more dangerous.

Numbness in your feet means you may not notice a blister, cut, or sore. A small injury can become infected without you realizing it, and in severe cases, infection can lead to amputation. Check your feet every day for cuts, blisters, redness, or swelling. Wear comfortable shoes that fit well, and see a doctor right away if you notice any injury.

Some people with neuropathy experience pain that is hard to treat. Your doctor can prescribe medications to ease the pain, and physical therapy or other treatments may help. Keeping your blood sugar controlled is the best way to prevent neuropathy from developing or getting worse.

Gum disease and tooth loss

High blood sugar makes it easier for bacteria to grow in your mouth, which increases your risk for gum disease and tooth decay. Gum disease is also more common and more severe in people with diabetes. Untreated gum disease can lead to tooth loss and can make blood sugar harder to control.

Brush your teeth twice a day with fluoride toothpaste, floss daily, and see a dentist at least twice a year. Tell your dentist that you have diabetes. If you notice red, swollen, or bleeding gums, or if your teeth feel loose, see your dentist right away.

Skin infections and slow healing

High blood sugar weakens your immune system, making it harder for your body to fight off infections. Cuts and sores also heal more slowly when blood sugar is high, because high blood sugar reduces blood flow to the skin. A minor scrape can become a serious infection if you are not careful.

Keep your skin clean and dry, especially between your toes and in skin folds. Treat any cuts or scrapes right away with soap and water, then cover them. If a wound does not start to heal within a few days, or if you see signs of infection (redness, warmth, pus, or swelling), see a doctor.

Frequently Asked Questions

Can I prevent these diseases if I have diabetes?

You cannot eliminate the risk, but you can reduce it significantly. Keeping your blood sugar, blood pressure, and cholesterol as close to target as possible, staying active, eating well, not smoking, and taking your medications as prescribed all lower your risk. Many people with diabetes never develop these complications.

How often should I be screened for these conditions?

Your doctor should check your blood pressure and cholesterol at every visit. You should have a dilated eye exam at least once a year, a kidney function test at least once a year, and a foot exam at least once a year. Ask your doctor what schedule is right for you based on your individual risk.

What if I already have one of these diseases?

Having both diabetes and another disease means you need to manage both carefully. Your doctor may prescribe additional medications and recommend lifestyle changes. The goal is to slow the disease and prevent complications. Regular monitoring and follow-up care are especially important.

Does type 1 diabetes carry the same risks as type 2?

Yes. Both types of diabetes can lead to heart disease, kidney disease, eye problems, and nerve damage if blood sugar is not well controlled. The risk depends more on how well you manage your blood sugar over time than on which type of diabetes you have.

What should I do if I notice symptoms of one of these diseases?

Contact your doctor right away. Do not wait for your next scheduled appointment. Early treatment of heart disease, kidney disease, eye problems, and nerve damage can prevent serious complications. For emergencies like chest pain or sudden vision loss, call 911.