Type 1 vs. Type 2 Diabetes: What Are the Differences?

Diabetes is a chronic condition that results in impaired blood glucose (sugar) regulation in the body. This can often bring about high blood glucose levels. However, there is more than one type of diabetes. The most common are type 1 and type 2 diabetes.

Type 1 diabetes is an autoimmune condition in which your immune system attacks and destroys the insulin-producing cells in your pancreas. As a result, your body is no longer able to make insulin.

Insulin is a hormone that helps decrease blood glucose levels. Type 1 diabetes often occurs in childhood or adolescence but can occur at any age. 

Type 2 diabetes is a chronic condition that develops slowly over time. With type 2 diabetes, your body doesn't use insulin properly, often resulting in high blood sugar levels. Over time, people with type 2 diabetes can also develop deficiencies in insulin production and require insulin replacement.

Type 2 diabetes is most commonly diagnosed in adults. However, more and more children are developing type 2 diabetes.

Make sure to see a healthcare provider for a diagnosis so that you can receive the proper treatment. 

Symptoms

The symptoms that occur with type 1 and type 2 diabetes are both due to high blood glucose levels and are very similar. However, a big difference between type 1 and type 2 diabetes symptoms is how quickly they appear.

Type 1 diabetes develops in stages. The first two stages do not have symptoms. In stage 1, the body begins to produce autoantibodies, which are the antibodies that attack the body's insulin-producing cells. In stage 2, the person develops glucose intolerance or dysglycemia. Symptoms don't become apparent until stage 3 and often come on suddenly.

In people with type 2 diabetes, symptoms usually appear much more gradually. Sometimes, people with type 2 diabetes do not notice any signs until blood glucose levels are very high.

Common symptoms of diabetes include:

• Frequent urination (unusual bed wetting in children is common with type 1)
• Feeling very tired
• Increased thirst
• Increased hunger
• Blurred vision
• Cuts, wounds, or bruises that don’t heal or heal slowly
• Unexplained weight loss (more common with type 1)
• Tingling, pain, or numbness in the hands and/or feet (type 2)
  

Causes

Both type 1 and type 2 diabetes are a result of improper blood sugar regulation by the body. However, the causes are very different.

Causes of Type 1 Diabetes

Type 1 diabetes is a chronic autoimmune condition in which the body’s immune system attacks the insulin-producing cells inside the pancreas. As a result, the body is no longer able to make insulin. Insulin is responsible for lowering blood glucose levels when they get too high. 

Researchers haven’t pinpointed an exact cause of type 1 diabetes. However, they have found that someone is more likely to develop type 1 diabetes if they have the following risk factors:

• Have an immediate family member with type 1 diabetes
• Have certain autoantibodies in their blood
• Had certain viral infections
• Had certain environmental triggers

Causes of Type 2 Diabetes

Type 2 diabetes is a chronic medical condition that occurs due to several factors, including certain lifestyle habits and genetics. These include:

• Family history of type 2 diabetes (parent or sibling with type 2 diabetes)
• Have prediabetes
• Had gestational diabetes (diabetes during pregnancy)
• Are 45 years or older
• Do not exercise regularly
• Are overweight or have obesity

In the United States, type 2 diabetes is more often diagnosed in these ethnicities: Black, Latinx, American Indian, Alaska Native, Pacific Islanders, or Asian.

Many people with type 2 diabetes often have insulin resistance (cells in the body don’t respond normally to insulin). Over time, if blood sugar levels in people with type 2 diabetes stay high, insulin-producing cells in the pancreas can become damaged and lose their ability to make and provide insulin for the body.

Diagnosis

The same tests and criteria are used to diagnose both type 1 and type 2 diabetes. The healthcare provider uses their clinical judgment initially to make the classification.

Type 1 diabetes often remains undiagnosed until symptoms appear during the third stage. It is possible to receive an earlier diagnosis, however. People with first- or second-degree relatives with type 1 diabetes may choose to be screened so the condition can be identified before it becomes symptomatic. 

Blood tests, such as autoantibody or genetic tests, can help to determine whether a person has type 1 versus type 2 diabetes if it is unclear or they don't respond well to oral medications to reduce blood sugar. If you don't have symptoms and you test positive for two or more type 1 diabetes autoantibodies, you have abnormal blood glucose levels, and you don't have type 2 diabetes, you will be diagnosed with stage 2 type 1 diabetes.

There are also other types of diabetes like maturity-onset diabetes of the young (MODY) or latent autoimmune diabetes in adults (LADA) as two examples.

Type 1 diabetes, previously known as “juvenile onset” or “insulin dependent” diabetes, is most often diagnosed in children and teens, though adults can also be diagnosed with type 1 diabetes. About 5% to 10% of all diabetes cases are type 1 diabetes.

Type 2 diabetes is most often diagnosed in adults over 45, though more and more children, teens, and young adults are being diagnosed with type 2 diabetes.

Diabetes can be diagnosed by using several different tests that check your blood glucose level:

• Fasting plasma glucose (FPG) test: Checks your blood glucose level when you haven’t eaten or drunk anything besides water for at least eight hours.
• A1C test: A blood test that provides an average of your blood glucose levels over the past two to three months.
• Random plasma glucose test: Measures your blood glucose level when you haven’t been fasting for at least eight hours.
• Oral glucose tolerance test (OGTT): Measures your blood glucose level after you have been fasting for at least eight hours. Then you are given a liquid high in glucose to drink, and your blood glucose levels are checked again two hours later.

Treatment

Because of the different causes and treatments for type 1 and type 2 diabetes, it is critical to receive a proper diagnosis. While the aim for diabetes treatment (to stabilize blood glucose levels) may be similar, the treatments for type 1 versus type 2 diabetes can be very different. 

Treatment for Type 1 Diabetes

If you have stage 2 type 1 diabetes, your healthcare provider may recommend treatment with a recently approved injectible medication called Tzield (teplizumab-mzwv). This medication can help delay the progression to stage 3 type 1 diabetes. It works by binding to the immune cells that attack your body's insulin-producing cells.

Once the body has progressed to stage 3 type 1 diabetes, it can no longer make insulin. People with stage 3 type 1 diabetes require exogenous (from outside the body) insulin to survive. Insulin can be administered via syringe or pen injection, insulin pump, or insulin inhaler. There are also other injectable medications available for people with type 1 diabetes.

People with type 1 diabetes must check their blood glucose levels regularly, usually numerous times a day. This can be done with a blood glucose monitor. However, many people with type 1 diabetes use a wearable continuous glucose monitor (CGM) that automatically and frequently checks their blood glucose levels throughout the day.

An artificial pancreas, or automated insulin-delivery system, is a newer treatment option available for people with type 1 diabetes. An artificial pancreas is a three-part wearable system that works together to mimic how a healthy pancreas controls blood glucose in the body.

As with anyone, a healthy diet and regular exercise are important for people with type 1 diabetes. People with type 1 diabetes often have to count carbohydrates in what they eat and drink to know the correct dosage for their insulin. 

Treatment for Type 2 Diabetes

People with type 2 diabetes often still produce some insulin in their body. Because of this, only some people with type 2 diabetes use insulin as part of their treatment plan. Oral medications (pills) or medication injections are commonly prescribed to people with type 2 diabetes. Currently, only people with type 2 diabetes can use pills to manage their diabetes.

Besides insulin, there are several different classes (types) of medications for type 2 diabetes, which work in different ways to help lower blood glucose levels. These include:

• Alpha-glucosidase inhibitors
• Biguanides
• Bile acid sequestrants
• Dopamine-2 agonists
• DPP-4 inhibitors
• Meglitinides
• SGLT2 inhibitors
• Sulfonylureas
• Thiazolidinediones (TZDs) 
• Oral combination therapy

Aside from medication and blood glucose monitoring, lifestyle habits are a big part of self-management with type 2 diabetes, such as:

• Regular physical activity
• Making healthy food choices
• Managing your blood pressure
• Keeping your cholesterol in normal ranges
• Losing weight, if needed

Despite the differences in treatment between type 1 and type 2 diabetes, a commonality between the two is that a big part of a diabetes care plan is self-management by the individual. Along with self-monitoring of blood glucose levels, regular visits with your healthcare team are important.

Providers on your diabetes healthcare team may include:

• Primary care provider
• Endocrinologist (​​a doctor who has special training on disorders of the endocrine system)
• Podiatrist
• Optometrist
• Dentist
• Pharmacist
• Diabetes educator
• Registered dietitian nutritionist

Prevention

Currently, there is no known way to prevent type 1 diabetes. However, by maintaining healthy blood glucose levels you can prevent or delay diabetes-related complications.

With many risk factors for type 2 diabetes being modifiable, there are ways to help prevent or delay the onset of type 2 diabetes. These include:

• Make healthy food choices
• Exercise regularly
• Lose weight, if needed
• Manage your blood pressure
• Keep your cholesterol in normal ranges
• Medications, if needed

Summary

Type 1 and type 2 diabetes are chronic medical conditions in which people need to self-manage their blood glucose levels. However, type 1 diabetes is an autoimmune condition and type 2 diabetes is largely related to lifestyle habits, as well as family history.

Diagnostic tests used for type 1 and type 2 diabetes are the same. Type 1 diabetes is more commonly diagnosed in children and teens while type 2 diabetes is usually diagnosed in adults—though anyone of any age can be diagnosed with either type of diabetes.

People with type 1 diabetes require insulin as part of their treatment plan, while people with type 2 diabetes might control their diabetes with diet, exercise, and/or medications. There is no known way to prevent type 1 diabetes. Type 2 diabetes may be prevented or delayed with lifestyle modifications and/or medications.

A Word From Verywell

Diabetes is a serious medical condition that requires lifelong management. Getting a proper diagnosis and treatment plan is essential to help you succeed with your diabetes management. Don’t be afraid to advocate for yourself if you have questions or concerns about your treatment plan. 

Make sure you have a support system to help you, including family, friends, and your healthcare team. While life with diabetes might sometimes seem daunting, you can lead a healthy, normal life by monitoring your blood glucose levels and following healthy lifestyle habits.