Diabetes is a chronic health condition that affects how your body uses blood sugar (glucose). 

There are many types of diabetes, but the most common types are type 1, type 2, and gestational diabetes. Some other, less common, types of diabetes include MODY and LADA. 

Let’s look at each of these.

The word diabetes on a dictionary page

Key Points

  • Almost 12 percent of the U.S. population has diabetes, with more than one million cases diagnosed each year.
  • Type 2 diabetes remains the most common form of diabetes, accounting for more than 90 percent of diabetes cases.
  • People of any age can get type 1 or type 2 diabetes. More and more children and young adults are diagnosed with type 2 diabetes, and more than half the cases of new type 1 diabetes occur in adults.
  • Knowing the risk factors for diabetes, getting tested regularly for diabetes, and seeking prompt medical care for diabetes-related symptoms can help ensure a proper diagnosis and appropriate treatment.
  • Lifestyle measures, including healthy eating, regular physical activity, and glucose monitoring are key parts of all diabetes treatment plans. However, medication may be needed, as well, to help manage diabetes and delay or prevent complications. 

Diabetes basics

Glucose is the body’s main source of energy, and it comes from the foods that you eat. When you eat, the carbohydrate in food gets broken down into glucose, which enters the bloodstream. As glucose levels rise in the blood, the pancreas releases insulin, a hormone that moves glucose from the blood into cells to be used for energy.

If you have diabetes, your body doesn’t make enough (or any) insulin; your body may also not be able to use the insulin it makes properly. 

Without enough insulin, blood glucose levels in the blood stay too high. Over time, high glucose levels can cause serious complications, such as heart disease, kidney disease, neuropathy (nerve damage), and eye problems — even blindness.

Diabetes statistics

According to the American Diabetes Association (ADA), as of 2021, 38.4 million Americans, which is 11.6 percent of the population, had diabetes. 

Of those, two million Americans have type 1 diabetes; this includes about 304,000 children and adolescents. Also as of 2021, 97.6 million Americans age 18 and older had prediabetes, a precursor to type 2 diabetes. 

In 2021, 1.2 million cases of diabetes were diagnosed. What’s concerning is that of the 38.4 million adults with diabetes, 8.7 million are undiagnosed. 

Types of diabetes

Type 1 diabetes

Type 1 diabetes is an autoimmune disorder that develops when the immune system mistakenly attacks and destroys the beta cells in the pancreas (these are the cells that make insulin). 

As a result, the body makes little or no insulin, causing blood glucose levels to rise dangerously high. About 5 to 10 percent of people with diabetes have type 1.

Until somewhat recently, the thought was that type 1 diabetes occurred mostly in children and adolescents, but epidemiological data has shown that more than half of all new cases of type 1 diabetes occur in adults

Type 1 diabetes causes

The causes of type 1 diabetes aren’t completely known; however, scientists believe that genes and environmental factors, such as viruses, can trigger this condition. A major study called TrialNet is looking at what causes type 1 diabetes, as well as ways to prevent or slow this condition. 

Type 1 diabetes risk factors

Risk factors for type 1 diabetes include: 

  • Age: While people of any age can get type 1, children between the ages of 10 and 14 have the highest occurrence of diagnoses.
  • Family history: Having a family member with type 1 diabetes is the biggest risk factor for developing this condition, although the type 1 nonprofit group JDRF states that “nearly 85% of diagnoses occur in people who have no family members with this disease.”

Dietary factors, such as eating too much carbohydrate, or being sedentary don’t cause type 1 diabetes. Also, there is no conclusive evidence that antibiotics, cow’s milk, gluten, or other environmental factors are culprits. Ongoing research continues to investigate the potential role of various environmental triggers. 

Type 1 diabetes symptoms

Symptoms of type 1 diabetes usually start quickly, in a matter of weeks. These may include:

  • Increased thirst 
  • Increased hunger
  • Frequent urination, often at night
  • Fatigue
  • Unexplained weight loss
  • Blurred vision
  • Dry mouth
  • Dry, itchy skin
  • Cuts and sores that are slow to heal
  • Numbness or tingling in the feet or hands

Stomach pain, nausea and vomiting, and sweet-smelling breath are other symptoms that can occur. These symptoms can indicate diabetic ketoacidosis (DKA), a serious and potentially life-threatening condition. 

Type 1 diabetes diagnosis

There are several blood tests that can be used to diagnose both type 1 and type 2 diabetes. The results below indicate a positive diagnosis of diabetes: 

  • A1c test: 6.5 percent or higher 
  • Fasting blood sugar: 126 mg/dL (7.0 mmol/L) or higher
  • Glucose tolerance test: A 2-hour blood sugar of 200 mg/dL (11.1 mmol/L) or higher
  • Random blood sugar: 200 mg/dL (11.1 mmol/L) or higher

You may also be tested for autoantibodies (only in type 1 diabetes), C-peptide (which shows if the body is making insulin), and ketones to help determine the type of diabetes you have. Of note, the presence of DKA is often the first sign of type 1 diabetes in a person not yet diagnosed.

Type 1 diabetes treatment

Type 1 diabetes is treated with insulin, given either as injections or by infusions from an insulin pump. In addition, monitoring blood glucose levels, controlling carbohydrate intake, and staying physically active are also important parts of the treatment plan.

Type 2 diabetes

With type 2 diabetes, cells in the body don’t use insulin properly. Also, the pancreas may not make enough insulin to keep glucose levels in a safe range. Type 2 diabetes is the most common type, accounting for 90 to 95 percent of diagnosed cases.

Type 2 diabetes typically develops in people over the age of 45, although more and more children, teens, and young adults are developing this condition.

Type 2 diabetes causes

Type 2 diabetes results primarily from insulin resistance, which happens when the cells in the muscles, fat, and liver don’t respond well to insulin and take up glucose from the blood. 

The pancreas makes more insulin to help move glucose from the blood into cells; however, over time, the pancreas may be unable to keep up with the increased demand.

Type 2 diabetes risk factors

You are more likely to develop type 2 diabetes if you have any of the following:

  • Prediabetes
  • Overweight or obesity
  • A family history
  • Are 35 years or older
  • Have a parent or sibling with type 2 diabetes
  • Have had gestational diabetes or given birth to a baby weighing over 9 pounds
  • Are an African American, Hispanic or Latino, American Indian, Alaska Native, Asian American, or Pacific Islander

Type 2 diabetes symptoms

Symptoms of type 2 diabetes can be the same as those for type 1 diabetes. But symptoms are much slower to develop in type 2 diabetes, and some people have mild or no noticeable symptoms. A lack of symptoms can delay getting proper treatment.

Type 2 diabetes diagnosis

Blood tests used to diagnose type 2 diabetes are the same as for type 1 diabetes. However, healthcare providers typically don’t order autoantibody or C-peptide tests for someone believed to have type 2 diabetes.

Type 2 diabetes treatment

Many people who have type 2 diabetes are able, at least initially, to manage their diabetes with a combination of weight loss, healthy eating, and regular physical activity.

Diabetes management guidelines often encourage healthcare providers to start diabetes medicine at diagnosis; this may include various types of diabetes pills and/or non-insulin injectable medicines. Over time, it’s not uncommon for people with type 2 diabetes to need insulin to manage their blood sugars

Gestational diabetes

Gestational diabetes is diabetes that occurs during pregnancy. It’s usually diagnosed in the 24th to 28th week of pregnancy. According to the U.S. Centers for Disease Control and Prevention (CDC), 2 percent to 10 percent of pregnancies in the U.S. are affected by gestational diabetes. 

Gestational diabetes causes

Gestational diabetes happens when hormones made by the placenta, along with the mother’s weight gain, cause insulin resistance. Insulin resistance makes it hard for the mother’s body to use insulin.

All pregnant women develop some insulin resistance in pregnancy, but some women don’t make enough insulin to overcome the resistance. This results in gestational diabetes. In most women with gestational diabetes, the condition goes away on its own soon after delivery.

However, women with gestational diabetes have a higher risk of developing type 2 diabetes compared with women who have never had gestational diabetes.

Gestational diabetes risk factors

Risk factors for gestational diabetes are:

  • Overweight or obesity
  • Physical inactivity
  • Having prediabetes
  • Family history of type 2 diabetes
  • Gestational diabetes during a previous pregnancy
  • Having previously given birth to a large baby
  • Polycystic ovary syndrome (PCOS)
  • Being of a certain race or ethnicity

Gestational diabetes symptoms

Many women don’t have gestational diabetes symptoms. If they do, the symptoms can be mild, such as being thirstier than usual or needing to urinate frequently. Some women may notice an increase in yeast infections or urinary tract infections.

Gestational diabetes diagnosis

Gestational diabetes is diagnosed with blood tests. These may include a:

  • Glucose screening test: After drinking a glucose drink, blood is drawn after an hour to check a blood glucose level. You will need to have a glucose tolerance test if the glucose reading is 140 mg/dL (7.8 mmol/L) or higher.
  • Glucose tolerance test: This test measures blood glucose levels before and after drinking a glucose drink. Blood glucose is checked one, two, and maybe three hours after. 

Your healthcare provider will explain what your results mean, depending on the type of testing you have. 

Gestational diabetes treatment

If you are diagnosed with gestational diabetes, you’ll need to follow a healthy eating plan, get regular physical activity, and monitor your blood sugars daily. 

Blood sugar goals are generally stringent during pregnancy. If lifestyle measures alone aren’t helping you to meet your blood sugar goals, your healthcare provider may start you on insulin, as other types of diabetes medicines lack long-term safety data.

Other forms of diabetes

Two less common types of diabetes are maturity-onset diabetes of the young (MODY) and latent autoimmune diabetes of adults (LADA).

Maturity-onset diabetes of the young (MODY)

MODY is a form of diabetes that develops during adolescence or young adulthood and accounts for up to 2 percent of all diabetes cases in the United States for people ages 20 and under.

Gene mutations are believed to cause MODY, affecting the pancreas’ ability to make insulin; this leads to high blood sugars and can ultimately cause diabetes complications.

Treatment may initially include a lower-carbohydrate eating plan. Eventually, though, as glucose levels increase, diabetes medication is needed, including insulin. Research shows that sulfonylureas, a class of diabetes pills, may actually be more effective than insulin in treating MODY.

It’s important to note that the approach to managing MODY must be tailored to the specific genetic mutation and its effect on insulin production and blood sugar regulation. Genetic testing can help determine the most appropriate treatment strategy.

Read more in: MODY Diabetes: Everything You Need to Know

Latent autoimmune diabetes of adults (LADA)

LADA is an autoimmune form of diabetes that starts in adulthood. It accounts for 2 to 12 percent of all cases of diabetes in adults. The criteria for diagnosing this form of diabetes are:

  • Age greater than 35 years
  • Positive autoantibodies to beta cells in the pancreas
  • Insulin independence for at least the initial six months after diagnosis

Unlike type 1 diabetes, the pancreas slowly stops making insulin with LADA. LADA is sometimes called “type 1.5 diabetes,” although some scientists argue that LADA is really a form of type 1 diabetes. 

A person who is diagnosed with type 2 diabetes but who is at a normal (healthy) weight and who is physically active could have LADA and should talk with their healthcare provider to get a proper diagnosis. 

Learn more in: LADA Diabetes (Latent Autoimmune Diabetes in Adults).

Final thoughts

Diabetes affects millions of people worldwide and has become more prevalent in the U.S. Type 2 diabetes accounts for more than 90 percent of diabetes cases and is largely preventable — and manageable — with lifestyle changes.

Other forms of diabetes impact people, as well. Be familiar with risk factors and symptoms of diabetes, and let your healthcare provider know if you have any of the classic symptoms, such as extreme thirst or frequent urination.

Not properly treating diabetes can lead to serious complications. But the good news is that there are more effective ways to monitor and manage diabetes than ever before.