Illustration of a Diabetes Type 2 finger prick test

What Is Type 2 Diabetes?

Type 2 diabetes is the most common type of diabetes. It occurs when the body resists or doesn't produce enough insulin, leading to higher blood sugar levels.

Type 2 diabetes is a chronic condition that occurs when your body isn't able to properly use insulin, a hormone made by the pancreas. People with type 2 diabetes either can't produce enough insulin, have cells that are resistant to the insulin they make, or have a combination of both. When your body lacks insulin, your blood glucose (or, blood sugar) rises.

The way your body uses insulin can seem complicated. Here's the breakdown: After you eat or drink, your body converts the nutrients from your food into glucose, or sugar. Once the glucose enters your bloodstream, your pancreas is able to release insulin into your bloodstream, which uses the glucose as energy to fuel your body or stores it for later use.

If you have type 2 diabetes, that process doesn't work as it should—either because your cells are resistant to the insulin your pancreas produces, or because your pancreas cannot produce enough insulin. Instead of your body using glucose as energy, the glucose remains in the bloodstream. Over time, high levels of glucose in the blood can affect your organs and tissues.

Getting treatment for type 2 diabetes is important. If left untreated, complications like heart disease, kidney disease, nerve damage, and vision loss can happen. This may sound scary, but type 2 diabetes is a common condition that can be managed with the right treatment and lifestyle changes.

Types of Type 2 Diabetes

Type 2 diabetes is the most common type of diabetes mellitus (diabetes), which accounts for 95% of all diabetes cases. There are four subtypes of type 2 diabetes, which include:

  • Severe insulin-deficient diabetes (SIDD): This subtype represents about 18% of cases. People with SIDD generally are young and have a healthy weight. They produce little insulin and may have a poor metabolism. Common complications of SIDD are blindness and nerve damage. 
  • Severe insulin-resistant diabetes (SIRD): SIRD accounts for about 15% of cases. People with SIRD may have obesity and can have insulin resistance. Kidney and liver issues are common among people with SIRD.
  • Mild obesity-related diabetes (MOD): Representing nearly 22% of cases, MOD usually affects people who have obesity. Unlike SIRD however, people with MOD do not resist insulin. Generally, MOD is a mild form of type 2 diabetes and causes very few complications.
  • Mild age-related diabetes (MARD): This is the most common subtype of type 2 diabetes and represents 39% of cases. People with MARD have some difficulty controlling their blood sugar levels. Generally, they have few complications. The risk of MARD usually increases with age.

Some people, may have a condition called prediabetes, which can occur when your blood sugar is slightly higher than normal, but not yet in the range for type 2 diabetes. Prediabetes affects one in three adults in the United States. You can reverse prediabetes through lifestyle changes, such as managing weight, eating nutritious foods, and getting regular exercise.

Type 2 Diabetes Symptoms

If you have type 2 diabetes, you may experience a wide range of symptoms, which include:

Symptoms can sometimes be so mild that you don't even notice any changes in your health. In the U.S., approximately half of all people with type 2 diabetes are unaware of their condition.

What Causes Type 2 Diabetes?

The primary cause of type 2 diabetes is insulin resistance. Unlike type 1 diabetes—which is not preventable—other factors can also increase your risk of developing type 2 diabetes, such as:

  • Weight: Obesity is associated with type 2 diabetes.
  • Physical activity: A lack of exercise puts you at risk of developing type 2 diabetes. Getting regular exercise can keep your blood sugar low and help your body convert sugar into energy.
  • Family history: If your family members have type 2 diabetes, you are also at a higher risk of developing the condition.
  • Gestational diabetes: This type of diabetes occurs when you have higher blood sugar levels when you are pregnant. Blood sugar levels usually return to normal after giving birth, but this condition may increase your risk of developing type 2 diabetes later in life.
  • Age: Type 2 diabetes affects all ages. However, people older than 45 are more likely to develop the condition.
  • Smoking: People who smoke are 30% to 40% more likely to develop type 2 diabetes than non-smokers.
  • Low HDL cholesterol: Having a low level of HDL ("good") cholesterol can increase your risk.
  • Polycystic ovary syndrome (PCOS): PCOS is a hormonal condition that affects the ovaries. People with PCOS may also have insulin resistance. About half of people with PCOS older than 40 have type 2 diabetes.
  • High blood pressure: Some medications that treat high blood pressure can increase your risk of getting type 2 diabetes.

How is Type 2 Diabetes Diagnosed?

Your healthcare provider can use a few tests that measure your blood sugar levels. They may also repeat their testing measures or order multiple tests to confirm or rule out a type 2 diabetes diagnosis.

It is best to only receive a diagnosis from your provider using one of the following tests. Keep in mind: don't diagnose yourself with type 2 diabetes using over-the-counter (OTC) blood testing equipment, like a blood glucose meter. 

Fasting Plasma Glucose (FPG) Test

Your healthcare provider may ask you to take a FPG test, which requires you to fast for at least eight hours. Usually, it best to schedule this test early in the morning so that you can fast overnight. You will have to skip breakfast, but you are able to sip on water.

During an FPG test, a healthcare provider will draw your blood. They will test your blood sample to check your blood glucose levels. Two FPG tests that show a blood glucose level greater than 126 milligrams of glucose per deciliter of blood indicate diabetes. 

A1C Test

This blood test measures your average blood sugar levels over the last three months from whenever you take the test. In contrast to the FPG test, you do not need to fast before receiving an A1C test.

During an A1C test, you will be asked to give a blood sample, which is usually drawn from a vein in your arm. When you get your test results back, you will receive a percentage which indicates what percentage of your blood proteins are coated with sugar. Normal A1C levels are less than 5.7%, prediabetes is 5.7% to 6.4%, and diabetes is 6.5% or higher.

Random Plasma Glucose (RPG) Test

Sometimes, your healthcare provider may choose to an RPG test to measure blood sugar levels. This test does not require fasting so your provider may ask you to take it at any point in the day.

When you receive your results, your provider can determine an official diabetes diagnosis if you have more than 200 milligrams of glucose per deciliter of blood.

Oral Glucose Tolerance Test (OGTT)

Also called a glucose tolerance test, an OGTT diagnoses prediabetes and diabetes. Similar to an FPG test, this test will also require you to fast overnight before you get your blood drawn.

After your healthcare provider takes a sample of your blood, they will ask you to consume a sugary drink. For the next two to three hours, they will repeatedly draw your blood to measure how your blood sugar levels respond to the sugary drink.

Urine Test

Historically, urine tests were more common to use than blood tests. However, urine test results are now less accurate than blood test results. Even so, your healthcare provider may still use it to measure blood sugar if there is any difficulty drawing your blood or if they're using the urine test as an alternative to a diabetes screening.

Treatments for Type 2 Diabetes

If you receive a diagnosis for type 2 diabetes, the goal of treatment is to bring your blood sugar levels down and keep them in a healthy range. Treatments can vary based on the severity of your condition, your lifestyle, and your overall health.

Some people with type 2 diabetes take oral medications to keep their blood sugar in control. Insulin injections are more common for people with type 1 diabetes, but your healthcare provider offer insulin injections if other treatments aren't working for you.

In most cases, your can manage your blood sugar by making healthy lifestyle changes, such as:

  • Eating a nutritious diet: A heart-healthy diet helps manage diabetes. Focus on fruits, vegetables, whole grains, lean proteins, and non- or low-fat dairy to keep your blood sugar in check. The American Diabetes Association (ADA) recommends following their Diabetes Plate Method, which involves filling half of your plate with non-starchy vegetables, a quarter of your plate with lean proteins (e.g., chicken or fish), and a quarter of your plate with carbohydrate foods, like beans and grains.
  • Getting regular exercise: Staying active can help keep your blood sugar low. Walking, bike riding, and strength training are good options. But, what's most important is finding exercise that is enjoyable and accessible for you.
  • Losing weight, if needed: Because obesity can be associated with higher blood sugar levels, in some cases, your healthcare provider may suggest losing a small amount of weight through a healthy diet and moderate exercise.

The research cited in this article claims that weight loss can prevent or help treat a chronic condition. An individual’s weight is affected by a variety of biological, environmental, and social factors. does not promote or condone weight loss that’s not under the care of a healthcare provider. Please contact your healthcare provider if you’re concerned about losing weight responsibly and healthfully.

How To Prevent Type 2 Diabetes

Nearly 90 million adults in the United States have prediabetes. About 84% of those people have no idea that their blood sugar is higher than average. It's possible to stop prediabetes and prevent it from progressing into type 2 diabetes.

The best way to prevent type 2 diabetes is to shift toward a healthier lifestyle. If you or your healthcare provider think you may be at risk for developing type 2 diabetes, you can try taking some of these steps to lower your risk:

  • Eating a diet low fat diet that is high in fruits, vegetables, whole grains, and lean proteins
  • Exercising regularly
  • Limiting tobacco and alcohol use
  • Keeping track of your health goals
  • Building a support system to hold you accountable to your goals

The National Diabetes Prevention Program offers a Lifestyle Change Program. The program pairs you with a health coach who helps you change your lifestyle. The coaches can counsel you on adopting a heart-healthy diet, fitting daily physical activity into your schedule, and reducing stress. Some programs are free. Other programs may have a feel, but some insurance plans may help you cover the cost.

Co-Occurring Conditions

People with type 2 diabetes may also be at risk for developing other conditions that can also affect their blood sugar levels and overall health. Some of these co-occurring conditions include:

  • Hypertension: Also known as high blood pressure, some evidence suggests that hypertension affects more than 80% of people with type 2 diabetes.
  • Heart disease: Hypertension also increases your risk of heart disease. Heart disease may occur in people with type 2 diabetes, affecting nearly 20% of people with the condition.
  • Obesity: Obesity is a common risk factor a for type 2 diabetes. About 78% of people with type 2 diabetes are overweight or obese. Managing your weight can sometimes help prevent or treat type 2 diabetes.
  • Hyperlipidemia: This condition refers to a high amount of fat in your blood. Hyperlipidemia impacts more than 75% of people with type 2 diabetes. Diabetes may lower your HDL ("good") cholesterol and raise your LDL ("bad") cholesterol and triglycerides. That said, keeping your blood sugar level within a healthy range can help.
  • Chronic kidney disease (CKD): CKD occurs when your kidneys gradually lose function. If untreated, CKD can lead to kidney failure. It affects nearly 25% of people with type 2 diabetes.

Living With Type 2 Diabetes

Type 2 diabetes can impact your your physical and emotional health. If you receive a diagnosis for type 2 diabetes, getting treatment early can help improve your symptoms and your overall quality of life.

When you have a chronic condition, you may experience sadness or frustration from time to time. It's OK to feel this way and it's important for you to know that these feelings are normal. But, you don't have to deal with your condition alone and there are ways to cope with your emotions.

Some ways to manage your overall health include:

  • Cooking healthy meals with your loved ones
  • Finding an exercise buddy to accompany you during your workouts
  • Listening to comforting music while you practice your meditation or deep breathing techniques
  • Staying active by engaging in your favorite hobbies and spending time with family and friends
  • Keeping in contact with your healthcare provider to ensure you are keeping your blood sugar in control
  • Reaching out to a mental health professional if you need additional support

Type 2 diabetes can be a life-changing diagnosis. But, making healthy changes can help you live a fulfilling life.

A Quick Review

People with type 2 diabetes do not produce enough or resist insulin. When your body does not have enough insulin, your blood sugar rises and leaves you at risk for developing serious complications if left untreated.

The good news is that getting a diagnosis and receiving proper treatment can help you manage the condition. While there is no cure for type 2 diabetes, medication and lifestyle changes can help lower your blood sugar.

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