Key takeaways

  • Consistently high blood sugar levels, a hallmark of type 2 diabetes, can inflict significant damage on blood vessels throughout the body, raising the risk of heart disease and stroke.
  • Type 2 diabetes can lead to several eye conditions, including diabetic retinopathy, which can cause vision loss if blood vessels in the eyes experience damage over time due to high blood sugar.
  • People with type 2 diabetes are more susceptible to infections and other oral health issues, such as periodontal disease, because high blood sugar levels can reduce saliva production and harm gums and tissues in the mouth.

The pancreas produces the hormone insulin, which helps cells utilize glucose, the body’s main energy source. Type 2 diabetes occurs when the body cannot respond to insulin correctly. Usually, over many years, insulin production decreases.

As a result, glucose may accumulate in the blood and cause people to experience high blood sugar levels. This can lead to several acute or chronic health complications. Acute problems, such as hyperglycemia (hypers) or hypoglycemia (hypos), occur quickly and can happen anytime.

However, chronic complications are long-term issues that develop gradually, which can range from heart and kidney disease to vision loss and nerve damage.

Infographic body map highlighting diabetes complicationsShare on Pinterest

The Centers for Disease Control and Prevention (CDC) notes that heart disease is common in the United States. People with diabetes might be twice as likely to develop heart disease or stroke as those without diabetes. They may also be more likely to develop heart disease at a younger age, and their risk increases the longer they have diabetes.

High blood sugar levels can damage the nerves and blood vessels that control the heart. This damage can lead to heart disease. People with diabetes are also more likely to have other risk factors for heart disease. These can include:

Coronary artery disease (CAD) is the most common form of heart disease. It results from an accumulation of cholesterol in blood vessels that supply oxygen and blood to the heart. This buildup of plaque can increase the risk of heart attacks and strokes.

These conditions can be symptomless, but a doctor can check blood pressure and perform a blood test to measure cholesterol and triglyceride levels. Managing blood sugar levels, along with blood pressure and cholesterol, through diet and exercise, can help reduce the risk of heart disease for people with diabetes.

Most eye conditions in people with diabetes are due to high blood sugar levels, which gradually damage blood vessels in the eyes.

In the short term, someone with diabetes may experience temporary vision loss due to high blood sugar levels affecting fluid levels or causing swelling in the tissues of the eyes. Vision will usually return if the person is able to manage their blood sugar levels. In the long term, damage to blood vessels may result in bleeding, scarring, or dangerously high pressure.

Conditions that can lead to long-term vision loss or blindness include:

Diabetic retinopathy is the most common eye disease in people with diabetes. This results from damage to blood vessels in the retina, the light-sensitive layer of tissue in the back of the eye. High blood sugar levels lead to blockages in these blood vessels, causing them to leak fluid or bleed. To compensate, the eyes grow new blood vessels that do not work well and are prone to leaking and bleeding.

Many diabetes-related eye conditions may not have any initial symptoms. Managing diabetes and having regular eye checkups can help prevent or delay vision issues from developing. If someone with diabetes experiences vision loss, they should receive urgent medical attention.

People living with diabetes are also at a higher risk of developing oral health complications. Untreated diabetes can affect the mouth in many ways, such as:

  • producing less saliva, causing the mouth to feel dry, and increasing the risk of cavities
  • inflamed and bleeding gums
  • higher susceptibility to infections inside the mouth
  • slower wound healing

Periodontal disease is common in people with diabetes. This serious infection can damage the gums, tissues holding the teeth, and bones. It can lead to pain, bad breath, chewing difficulties, and even tooth loss. Issues with blood sugar regulation/management can increase the risk of gum problems, and the infection itself can also cause blood sugar levels to rise, making it more difficult to manage.

Other oral problems can include dry mouth and thrush. Dry mouth occurs due to a lack of saliva and can cause soreness, ulcers, infections, and tooth decay. Diabetes can also increase glucose levels in the saliva, creating a suitable environment for pathogens and resulting in fungal infections, such as thrush.

Alongside diabetes management, people should maintain oral hygiene and regularly check their mouths to help avoid these complications. If they notice any discomfort or unusual symptoms, they should visit their dentist.

People living with type 2 diabetes are at a higher risk of developing kidney disease. Evidence suggests that roughly one in three adults with diabetes has chronic kidney disease (CKD), which causes a slow and progressive loss of kidney function.

Type 2 diabetes is a leading cause of kidney failure. It occurs when high blood sugar levels damage blood vessels in the kidneys and the tiny filters, known as nephrons. Many people with diabetes may also develop high blood pressure, which can further damage the kidneys.

Kidney disease can develop slowly with few symptoms, so many people may not be aware until the condition advances. However, doctors check a person’s urine for microalbumin every 12 months. This test for small amounts of protein in the urine is usually the first sign that diabetes is affecting the kidneys. Additionally, people can take steps to manage their blood sugar, blood pressure, and cholesterol levels to improve kidney health.

Neuropathy refers to nerve damage, and diabetic neuropathy describes nerve damage that occurs due to diabetes. Over time, high levels of sugar or fats in the blood damage the nerves in the body.

There are different types of diabetic neuropathies, which include:

  • Peripheral neuropathy: Peripheral neuropathy is the most common form of diabetic neuropathy. It affects the nerves in the hands, feet, legs, and arms.
  • Autonomic neuropathy: This affects the autonomic nerves, which control involuntary functions of the body, such as digestion, urination, or heart rate.
  • Thoracic/lumbar radiculopathy: Radiculopathy damages nerves present in the torso and typically affects a band of the chest or abdominal wall.
  • Mononeuropathies: This describes damage to any individual nerve.

To help prevent neuropathy, people should aim to control their diabetes by managing their blood sugar, blood pressure, and cholesterol levels. Additionally, they should regularly check parts of their body, such as the feet, and take good care of them. It is advisable for people to visit a doctor for a neurological exam at least once a year.

Skin complications can be one of the first visible signs of diabetes. High blood sugar levels can result in dehydration, inflammation, and issues with circulation, which can all impact the skin.

Skin conditions that may occur in people living with type 2 diabetes can include:

  • Necrobiosis lipoidica: Necrobiosis lipoidica causes small, solid bumps that progress to patches of swollen, hard skin that may look like scars.
  • Acanthosis nigricans: Acanthosis nigricans causes a darker patch of skin to appear, typically around the neck, armpits, and groin.
  • Digital sclerosis: People may develop tight, thick, waxy skin on the backs of their hands.
  • Blisters: Also known as bullosis diabeticorum, some people may erupt in blisters.
  • Skin infections: People with diabetes are more likely to develop skin infections, which may cause hot, swollen, or painful skin.
  • Diabetic ulcers: Due to slower wound healing, people with diabetes are prone to open wounds known as ulcers.
  • Diabetic dermopathy: Diabetic dermopathy is a harmless condition that causes spots or lines to form on the skin.
  • Eruptive xanthomatosis: Eruptive xanthomatosis results in bumps that look similar to pimples.
  • Granuloma annulare: Granuloma annulare causes a rash with defined ring or arc-shaped raised areas on the skin.
  • Xanthelasma: Xanthelasma causes a person to develop scaly patches around the eyes.
  • Dry, itchy skin: Other conditions or issues with circulation can cause dry and itchy skin.

It is advisable for individuals with diabetes to be aware of potential skin complications and learn how to check for skin problems themselves. If a person notices any symptoms, they should contact their doctor.

There are many strategies people can apply to help prevent their risk of diabetic complications.

For example, individuals can follow the diabetes ABCs to help manage their condition:

  • A — getting regular A1C tests: These tests show a person’s average blood sugar levels over the past 3 months.
  • B — regulating blood pressure: High blood pressure can cause further damage to blood vessels.
  • C — managing cholesterol levels: Too much “bad” cholesterol can increase the risk of heart attack or stroke.
  • S — stopping smoking: Smoking can also damage blood vessels and negatively impact blood pressure and cholesterol.

People can also make the following lifestyle changes to help manage their diabetes:

A diabetes healthcare team can also provide advice to help someone manage their diabetes, such as scheduling regular checkups and tests alongside diet and lifestyle advice.

Visit our diabetes hub for more on type 2 diabetes, including treatments and ways to manage the condition.

The most life-threatening complications of diabetes are heart disease and stroke.

The potential health complications of type 2 diabetes are broad and can systematically affect the body in many ways. If left untreated, these complications can be severe and even life threatening.

Taking steps to control blood sugar levels and following a healthy lifestyle is an effective way to help prevent or delay health issues that may result from diabetes.

People can also work closely with their diabetes healthcare team to help manage the condition. If they have any health questions about diabetes, they can discuss these with their doctor.