What is diabetes? Types, causes and how it is managed

Diabetes is one of the most common long-term health conditions in the world. It is also one of the most misunderstood. This article explains in plain words what diabetes is, the different types, who is more likely to get it, and what managing it involves.

What is diabetes?

Your body turns much of the food you eat into glucose, which is also called blood sugar. Glucose is the main fuel for your cells. A hormone called insulin, made by an organ called the pancreas, moves glucose out of the blood and into the cells.

According to the US National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), diabetes is a disease in which blood glucose is too high. This happens when the body makes too little insulin, makes none, or does not use insulin properly. Over time, high blood sugar can damage the eyes, kidneys, nerves and heart. The WHO describes diabetes as a chronic condition, meaning it is long-lasting.

The main types of diabetes

• Type 1 diabetes: The immune system destroys the cells in the pancreas that make insulin, so the body makes little or none. People with type 1 diabetes need insulin every day. It is usually found in children and young adults, but it can appear at any age.
• Type 2 diabetes: The body does not use insulin well, and the pancreas may not make enough to keep blood sugar normal. This is the most common type. The NIDDK, citing the US Centers for Disease Control and Prevention (CDC), says it makes up about 90% to 95% of cases. The WHO says it accounts for more than 95% of cases worldwide and is often preventable.
• Gestational diabetes: This starts during pregnancy. It usually goes away after the baby is born, but it raises the later risk of type 2 diabetes for the mother.
• Prediabetes: Blood sugar is higher than normal but not high enough to be called diabetes. It raises the risk of type 2 diabetes and heart disease.
• Other types: Some rare forms come from a change in a single gene. Others follow pancreas surgery or damage to the pancreas from other conditions.

Who is more likely to get diabetes?

The risk factors depend on the type. For type 2 diabetes, the NIDDK lists being overweight or having obesity, and having a family history of the disease. The NIDDK also says that for type 1 diabetes, having a parent or sibling with it raises the risk. Pregnancy brings the chance of gestational diabetes.

Many people have diabetes without knowing it. The NIDDK, citing CDC figures from the United States, reports that nearly 1 in 4 adults with diabetes did not know they had it. According to the WHO, 830 million people were living with diabetes in 2022, up from 200 million in 1990.

Why does high blood sugar matter?

Blood sugar that stays high for years can harm blood vessels and nerves. The WHO lists heart attack, stroke, kidney failure, vision loss and nerve damage in the feet as possible results. These problems are not certain for everyone, and good care can lower the risk. The NIDDK says that managing blood glucose, blood pressure and cholesterol can help prevent future health problems.

How is diabetes managed?

Management depends on the type. A doctor decides the right plan for each person.

• People with type 1 diabetes need daily insulin, according to the NIDDK.
• For type 2 diabetes, the NIDDK describes lifestyle changes such as losing weight or preventing weight gain. The CDC lists healthy eating, physical activity, prescribed medicine, diabetes education and keeping medical appointments as helpful parts of care.
• The CDC notes that there is no cure for diabetes yet, which is why steady, long-term care matters.

When to see a doctor

Diabetes is found with blood tests. The CDC says that type 2 diabetes may cause no noticeable symptoms, so testing matters for people at risk. If you are worried about your risk, or you notice signs such as unusual thirst, passing urine more often, constant tiredness or weight loss you cannot explain, talk with a doctor and ask whether you should be tested.

Sudden severe symptoms need urgent care. These include trouble breathing, fruity-smelling breath, fainting, or stomach pain with vomiting in someone who has diabetes, which can be signs of a dangerous condition called diabetic ketoacidosis. In an emergency, call your local emergency number (112 in India, 911 in the United States).

This article is for education only. It does not diagnose any condition or replace advice from your own doctor.