Type 2 Diabetes

Type 2 diabetes happens when your body can’t use insulin properly. Without treatment, Type 2 diabetes can cause various health problems, like heart disease, kidney disease and stroke. You can manage this disease by making lifestyle changes, taking medications and seeing your healthcare provider for regular check-ins.


What is Type 2 diabetes?

Type 2 diabetes (T2D) is a chronic condition that happens when you have persistently high blood sugar levels (hyperglycemia).

Healthy blood sugar (glucose) levels are 70 to 99 milligrams per deciliter (mg/dL). If you have undiagnosed Type 2 diabetes, your levels are typically 126 mg/dL or higher.

T2D happens because your pancreas doesn’t make enough insulin (a hormone), your body doesn’t use insulin properly, or both. This is different from Type 1 diabetes, which happens when an autoimmune attack on your pancreas results in a total lack of insulin production.

How common is Type 2 diabetes?

Type 2 diabetes is very common. More than 37 million people in the U.S. have diabetes (about 1 in 10 people), and about 90% to 95% of them have T2D.

Researchers estimate that T2D affects about 6.3% of the world’s population. T2D most commonly affects adults over 45, but people younger than 45 can have it as well, including children.


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Symptoms and Causes

Symptoms include increased thirst, frequent urination, fatigue, increased hunger, slow healing and more.
Symptoms of Type 2 diabetes tend to develop slowly over time. It’s important to see a healthcare provider if you have them.

What are the symptoms of Type 2 diabetes?

Symptoms of Type 2 diabetes tend to develop slowly over time. They can include:

People assigned female at birth (AFAB) may experience frequent vaginal yeast infections and/or urinary tract infections (UTIs).

If you have these symptoms, it’s important to see your healthcare provider. Simple blood tests can diagnose T2D.

What causes Type 2 diabetes?

The main cause of Type 2 diabetes is insulin resistance.

Insulin resistance happens when cells in your muscles, fat and liver don’t respond as they should to insulin. Insulin is a hormone your pancreas makes that’s essential for life and regulating blood sugar levels.

If your body isn’t responding to insulin properly, your pancreas has to make more insulin to try to overcome your increasing blood glucose levels (hyperinsulinemia). If your cells become too resistant to insulin and your pancreas can’t make enough insulin to overcome it, it leads to Type 2 diabetes.

Several factors can contribute to insulin resistance, including:

Is Type 2 diabetes genetic?

The cause of T2D is complex, but researchers know that genetics play a strong role. Your lifetime risk of developing T2D is 40% if you have one biological parent with T2D and 70% if both of your biological parents have it.

Researchers have identified at least 150 DNA variations linked to the risk of developing T2D — some increase your risk and others decrease it. Some of these variations may directly play a role in insulin resistance and insulin production. Others may increase your risk of T2D by increasing your tendency to have overweight or obesity.

These genetic variations likely act together with health and lifestyle factors to influence your overall risk of T2D.

What are the risk factors for Type 2 diabetes?

You’re more likely to develop Type 2 diabetes if you:

As T2D symptoms typically come on slowly, it’s important to see your primary care provider regularly if you’re at risk for the condition. This way, they can do screenings, like a basic metabolic panel (BMP), to check on your blood sugar levels. It’s better to catch T2D earlier rather than later.


Diagnosis and Tests

How is Type 2 diabetes diagnosed?

The following blood tests help your healthcare provider diagnose Type 2 diabetes:

  • Fasting plasma glucose test: This lab test checks your blood sugar level. You typically need to get this test in the morning after an eight-hour fast (nothing to eat or drink except water). A result of 126 mg/dL or higher means you have diabetes.
  • Random plasma glucose test: This lab test also checks your blood sugar, but you can get it at any time without fasting. A result of 200 mg/dL or higher means you have diabetes.
  • A1C test: This lab test measures your average blood sugar levels over the past two to three months. A result of 6.5% or higher means you have diabetes.

In some cases, your provider may order an autoantibody blood test to see if you have Type 1 Diabetes instead of T2D.

Management and Treatment

What is the treatment for Type 2 diabetes?

Unlike many health conditions, you mainly manage T2D on your own with medical guidance and support from your healthcare team. This could include your:

Your team should also include family members and other important people in your life. Managing T2D can be challenging — you have to make several decisions every day for it. But everything you do to improve your health is worth it.

The core features of Type 2 diabetes management include:

  • Lifestyle changes, like more exercise and eating adjustments.
  • Blood sugar monitoring.
  • Medication.

Exercise for Type 2 diabetes

Regular activity is important for everyone. It’s even more important if you have diabetes. Exercise is good for your health because it:

  • Lowers your blood sugar level without medication in the short term and long term.
  • Burns calories and may help with weight loss.
  • Improves blood flow and blood pressure.
  • Increases your energy level and boosts your mood.
  • Helps with stress management.

Talk to your provider before starting any exercise program. You may need to take special steps before, during and after physical activity, especially if you take insulin. The general goal is to get at least 150 minutes per week of moderate-intensity physical activity.

Type 2 diabetes diet

Ask your healthcare provider or registered dietitian to recommend a meal plan that’s right for you. What you eat, how much you eat, and when you eat are all important in keeping your blood sugar levels in the range that your healthcare team recommends.

The key to eating with Type 2 diabetes is to eat a variety of nutritious foods from all food groups, in the amounts your meal plan outlines. In general, these types of foods can help support healthy blood sugar levels:

  • Lean proteins, like chicken, eggs, fish and turkey.
  • Non-starchy vegetables, like broccoli, green beans, salad greens and cucumbers.
  • Healthy fats, like avocados, nuts, natural peanut butter and olive oil.
  • Complex carbohydrates, like beans, berries, sweet potatoes and whole-wheat bread.

Blood sugar monitoring

Monitoring your blood sugar is essential to finding out how well your current treatment plan is working. It gives you information on how to manage diabetes on a daily — and sometimes even hourly — basis. The results of blood sugar monitoring can help you make decisions about food, physical activity and dosing insulin.

Several things can affect your blood sugar. You can learn to predict some of these impacts with time and practice, while others are very difficult or impossible to predict. That’s why it’s important to check your blood sugar regularly if your healthcare provider recommends doing so.

There are two main ways you can monitor your blood sugar at home if you have diabetes:

You may choose either or both methods for a variety of reasons, such as:

  • Your access to the technology, which can vary due to cost and medical insurance coverage.
  • How often your healthcare provider recommends checking your blood sugar.
  • The medications you’re taking.
  • Your overall health.

Type 2 diabetes medications

Your healthcare provider may recommend taking medication, in addition to lifestyle changes, to manage Type 2 diabetes. These include:

  • Oral diabetes medications: These are medications that you take by mouth to help manage blood sugar levels in people who have T2D but still produce some insulin. There are several types. The most commonly prescribed one is metformin. Your provider may prescribe more than one oral diabetes medication at a time to achieve the best blood glucose management.
  • GLP-1 and dual GLP-1/GIP agonists: These are injectable medications that mainly help manage blood sugar levels in people with T2D. Some GLP-1 agonists can also help treat obesity.
  • Insulin: Synthetic insulin directly lowers blood sugar levels. There are several types of insulin, like long-acting and short-acting types. You may inject it with syringes or pens, use inhaled insulin, or use an insulin pump.
  • Other medications: You may take other medications to manage coexisting conditions, like high blood pressure and high cholesterol.


Can Type 2 diabetes be reversed?

Type 2 diabetes is a chronic (long-term) disease, which means you must manage it for the rest of your life. There’s no cure for T2D. But you can manage it — with lifestyle changes, medication and blood sugar monitoring — in a way that keeps your blood sugar levels in a healthy range. If you stop managing it or undermanage it, your blood sugar levels will go back up.


Can I prevent Type 2 diabetes?

Certain strategies can help lower your risk of developing Type 2 diabetes or delay its onset, including:

  • Exercising regularly (at least 150 minutes a week).
  • Maintaining a weight that’s healthy for you.
  • Eating nutritious food.
  • Not smoking.

Unfortunately, some people have such strong genetic risk factors that even lifestyle changes aren’t enough to prevent developing T2D.

Outlook / Prognosis

What is the outlook for Type 2 diabetes?

If you have Type 2 diabetes, your outlook depends on several factors, like:

  • Your age at diagnosis.
  • How often and how well you’re able to keep your blood sugar levels in range.
  • If you have other conditions, like high blood pressure or high cholesterol.
  • Your access to healthcare, diabetes management tools and medication, nutritious foods and support from loved ones.

Untreated or undermanaged T2D can lead to a range of health conditions.

What are the complications of Type 2 diabetes?

As your blood touches virtually every part of your body, having undermanaged Type 2 diabetes that results in continuous high blood sugar over a long period of time can damage several areas of your body.

Potential complications of Type 2 diabetes include:

Cardiovascular disease, including:

Eye conditions, including:

Additional complications include:

Short-term complications of T2D

Hyperosmolar hyperglycemic state (HHS) is a life-threatening complication of Type 2 diabetes. HHS happens when your blood sugar levels are too high for a long period, leading to severe dehydration and confusion.

Symptoms of HHS usually come on slowly and can take days or weeks to develop. Symptoms include:

  • Very high blood sugar level (over 600 mg/dL).
  • Mental changes, such as confusion, delirium or experiencing hallucinations.
  • Loss of consciousness.
  • Dry mouth and extreme thirst.
  • Frequent urination.
  • Blurred vision or loss of vision.
  • Weakness or paralysis that may be worse on one side of your body.

HHS is life-threatening and requires immediate medical treatment. If you experience these symptoms, call 911 or your local emergency services number.

Living With

How do I take care of myself if I have Type 2 diabetes?

Type 2 diabetes is a complex condition that requires daily management, effort and planning. Some tips that can help you manage T2D include:

  • Try to stick to healthy lifestyle changes: Regular exercise and healthy eating plans are core parts of T2D management. Set small goals and make one change at a time to prevent becoming overwhelmed.
  • Check your blood sugar regularly Checking your blood sugar with a fingerstick and meter and/or using a continuous glucose monitor (CGM) is crucial to managing diabetes and preventing complications. Follow your provider’s guidance for how often you should be checking it.
  • Take your medication regularly: Follow your healthcare provider’s instructions for taking your medications (if applicable).
  • See your diabetes provider regularly: It’s important to see the provider who helps you manage T2D regularly to be sure that your management plan is working. Don’t be afraid to ask them specific questions.
  • See your other providers regularly, especially your eye doctor: Type 2 diabetes can cause complications in various areas of your body, but especially your eyes. It’s important to see your eye doctor (ophthalmologist) at least yearly so that they can check the health of your eyes.
  • Have a sick day plan: Talk with your diabetes provider about how to take care of yourself and manage T2D when you’re sick. Illness can make it more difficult to manage blood sugar levels and can trigger HHS.
  • Stay educated: Don’t be afraid to ask your provider questions about T2D. The more you know about T2D and your management, the more likely you’ll be able to live healthily and prevent complications.
  • Find community: Connecting with other people who have T2D — whether in-person or online — can help you feel less alone.
  • Take care of your mental health: People with diabetes are two to three times more likely to have depression and are 20% more likely to be diagnosed with anxiety than those without diabetes. Living with a chronic condition that requires constant care can be overwhelming. It’s important to talk to a mental health professional if you’re experiencing signs of depression and/or anxiety.

When should I see my healthcare provider if I have Type 2 diabetes?

You’ll need to have regular appointments with your healthcare team to be sure you’re on track with your T2D management plan. As your body, life and routines change, your management will need to, as well. Your healthcare team can provide new strategies that are unique to your needs.

If you develop symptoms of any diabetes complications, be sure to see your provider as soon as possible.

A note from Cleveland Clinic

Type 2 diabetes involves constant day-to-day care and management. While it’ll likely be very overwhelming at first, over time you’ll get a better grasp on how to manage the condition and how to be in tune with your body.

Be sure to see your healthcare team regularly. Managing Type 2 diabetes involves a team effort — you’ll want both medical professionals and friends and family on your side. Don’t hesitate to reach out to them if you need help.

Medically Reviewed

Last reviewed on 11/08/2023.

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