How many types of diabetes are there?

These different types all require prompt diagnosis

By Jennifer Larson | Nov. 1, 2021 Medically reviewed by Lindsey Hudson, APRN, NP-C, CDCES

Diabetes, or diabetes mellitus, is a chronic health condition that affects how your body uses food for energy. Your body isn’t able to move sugar, or glucose, from your bloodstream into your cells, so you end up with a surplus in your bloodstream.

Approximately 34.2 million people in the United States are living with diabetes, according to the Centers for Disease Control and Prevention’s 2020 National Diabetes Statistics Report. That represents 10.5% of the population. But not everyone has the same type of diabetes, which is why it’s important to know the different types.

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4 types of diabetes

There are four main types of diabetes: Type 1 diabetes, Type 2 diabetes, gestational diabetes, and a condition known as prediabetes, in which you have higher-than-normal blood glucose levels but not quite high enough (yet) to qualify as Type 2 diabetes.

With all four, prompt diagnosis is critical—and so is compliance with your diabetes treatment. Over time, high blood sugar levels can damage your blood vessels and raise your risk of developing certain health problems (some life-threatening), so it’s important to begin treatment—and stick with it faithfully—as soon as you get diagnosed.

But don’t despair. Regardless of what form of diabetes you might have, you can live a very full, healthy life. Adopting and embracing positive behavioral changes can not only lead to effective diabetes management, but it will also help you live a healthier life overall, says Lucille Hughes, DNP, the director of diabetes education for Mount Sinai South Nassau in Oceanside, New York.

Compare common types of diabetes
	Prevalence	Definition	Risk factors	Treatment
Type 1 diabetes	5%-10% of 34.2 million Americans who have diabetes	Pancreas does not make any insulin or not enough insulin to move sugar out of bloodstream and into cells	Having a close relative with Type 1 diabetes	Insulin therapy
Type 2 diabetes	90%-95% of 34.2 million	Having high blood sugar levels that average out to be 6.5% or greater as measured by an A1C test or fasting blood glucose level 126 or greater	Being overweight or having obesity Leading a sedentary lifestyle Being over 45 years of age Having a family history of Type 2 diabetes Having a history of smoking Being in certain racial/ethnic groups Having PCOS Having high cholesterol Having high blood pressure	Lifestyle changes to improve diet and increase exercise Weight loss Insulin therapy Metformin or other medications
Prediabetes	88 million	Having elevated blood sugar levels (A1c between 5.7% and 6.4% or fasting blood glucose level 100-125) that are higher than normal but not quite high enough to be Type 2 diabetes	Same as Type 2 diabetes	Positive lifestyle changes to help you achieve and maintain a healthy weight, such as increased physical activity
Gestational diabetes	5%-10% of pregnancies each year	Elevated blood sugar levels during pregnancy	Having a family history of prediabetes or Type 2 diabetes Being 25 or older Being overweight before pregnancy Being certain racial/ethnic groups	Insulin may be necessary for some Healthy diet and exercise

Type 1 diabetes

Formerly known as juvenile diabetes or insulin-dependent diabetes, Type 1 diabetes is much less common than Type 2. The CDC estimates that 5%-10% of people with diabetes have Type 1 diabetes. People with a close family member with Type 1 diabetes are at increased risk.

When you have Type 1 diabetes, your pancreas either doesn’t produce insulin at all or makes only a small amount of this hormone—not enough to help the sugar in your bloodstream enter your cells to be used for energy. As a result, your blood sugar levels are too high.

According to the American Diabetes Association (ADA), the symptoms of Type 1 diabetes can include:

Unusual thirst
Frequent urination or urge to urinate
High levels of fatigue
Unusual level of hunger
Blurry vision
Weight loss
Bruises or cuts that take longer to heal

If you or your child develop any symptoms of high blood sugar, you should seek medical care right away. A healthcare provider can begin the process of diagnosis by testing your blood sugar levels and possibly running a test to detect autoantibodies common in people with Type 1 diabetes.

Once you’re diagnosed, you will need to frequently monitor your blood sugar levels and ketones, and you’ll begin treatment with insulin, either via injection or insulin pump, to keep your blood sugar levels within a healthy range. When your body doesn’t have enough insulin to get sugar from your bloodstream into your cells, a very serious complication called diabetic ketoacidosis can develop. You also have to watch out for signs of low blood sugar, or hypoglycemia.

Over time, you can develop other complications from Type 1 diabetes. These can include diabetic neuropathy, diabetic retinopathy, and nephropathy. However, maintaining good control over your blood sugar levels can help lower the risk.

Type 2 diabetes

The vast majority of diabetes cases are Type 2 cases. About 90%-95% of the 34 million Americans with diabetes have Type 2.

Similar to Type 1 diabetes, with Type 2 diabetes your body still has a problem with moving sugar into your cells—but not because your pancreas stopped producing insulin. Your pancreas continues to make insulin, but your cells aren’t sensitive to it and can’t use the insulin the way they are supposed to.

People who are more susceptible to developing Type 2 diabetes are those who are overweight, lead a sedentary lifestyle, are 45+, have a family history of Type 2, or have a history of smoking. Certain races and ethnic groups are also at higher risk, as are people who have polycystic ovary syndrome, high cholesterol, or high blood pressure.

Type 2 diabetes is typically diagnosed with a glycated hemoglobin blood test or A1C test, which reports your average blood sugar levels as a percentage over the past three months. A normal number would be below 5.7%. To qualify for a Type 2 diabetes diagnosis, the number would be 6.5% or above.

As for symptoms, they’re similar to those of Type 1 diabetes. “The onset of Type 2 diabetes is usually slower, and the symptoms are not as noticeable as those for Type 1 diabetes,” says Aleida Saenz, APRN, FNP-BC, CDCES, the director of patient education at the Diabetes Research Institute (DRI). “For these reasons, many people mistakenly overlook the warning signs. They might also think that the symptoms are the signs of other conditions, like aging, overworking, or hot weather.” Over time, you can develop similar complications from Type 2 diabetes as those of Type 1 diabetes.

Once diagnosed, medication or insulin may be necessary. Metformin is commonly prescribed for people with Type 2; it lowers your liver’s glucose production and improves your body’s sensitivity to insulin, according to the Mayo Clinic. There is a wide array of other oral diabetes medications in a variety of drug classes that you might take, such as sulfonylureas, meglitinides, SGLT2 inhibitors, alpha-glucosidase inhibitors, thiazolidinediones, DPP-4 inhibitors, and others.

Many people with Type 2 diabetes are able to lower their blood sugar levels by making behavioral changes, such as losing some weight and improving their diets.

Gestational diabetes

As you might suspect from the name, gestational diabetes affects pregnant people. It’s a condition that develops in pregnant women when their blood sugar levels are too high. Between 2% and 10% of all pregnancies each year in the U.S. are affected by gestational diabetes, according to the CDC.

A screening test between the 24th and 28th week of pregnancy is routine: A woman will undergo an oral glucose tolerance test to gauge her blood sugar levels.

Many, but not all, pregnant women will need insulin injections during their pregnancy after they’re diagnosed with gestational diabetes. For many, blood sugar levels will drop back down to normal after they deliver their babies. But they will still need some follow-up monitoring in the postpartum period—and they may also need to stay vigilant longer than that as half of all pregnant women with gestational diabetes go on to develop Type 2 diabetes.

Prediabetes

Prediabetes can be a precursor to Type 2. When diagnosed with prediabetes, it means your blood sugar levels are elevated beyond the normal level—but not high enough to qualify as Type 2 diabetes yet. On an A1C test, your levels would hover somewhere between 5.7% and 6.4%.

Approximately 88 million people in the U.S. have prediabetes, according to the CDC’s 2020 National Diabetes Statistics Report. The prevalence is higher among men than women. And unfortunately, you may not even realize that you have prediabetes, as the CDC estimates that as many as 84% of people with prediabetes are unaware. The danger there is you might not take steps to reverse it before it becomes Type 2 diabetes.

“The complications are silent,” says Hughes. “So, the patient is not getting any physical reinforcement to say that their behavior isn’t good.” Since you might not realize you have prediabetes, you might want to talk to your healthcare provider about having your blood sugar levels checked yearly, especially if you have any of the risk factors (which are the same as with Type 2 diabetes).

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How to lower your risk of diabetes

You can control some but not all of the risk factors of the four types of diabetes. However, if you have any of these risk factors, discuss your diabetes risk with your healthcare provider. The earlier you can intervene, the better, explains Nilem Patel, MD, an endocrinologist in Los Angeles, California, who is affiliated with Adventist Health-White Memorial. “In general, you’re trying to fend off the complications of diabetes as long as you can,” she says.

Along with glucose management, these steps can help:

Stick to a healthy meal plan that provides the nutrients you need without sending your blood sugar levels soaring. Often, this means restricting carbohydrates. Consult a registered dietitian to get some help with meal planning.
Maintain a healthy body weight. If you’re overweight, losing just 5%-10% of your total body weight can help you improve your blood sugar levels and decrease insulin resistance.
Reduce your portion sizes. It’s easy to eat too much without even realizing it, so be sure to educate yourself on serving sizes and tricks, such as the recommended 3 oz. serving of meat is about the size of your palm.
Move more throughout the day. Being active will make your body more sensitive to insulin, according to the CDC. So, take the stairs instead of the elevator, or walk around when you’re talking on the phone.
Exercise at least 30 minutes five days per week. This will help you lose a few pounds and maintain a healthy weight once you get there. Exercise also lowers your risk of heart disease and nerve damage, which increase when you have diabetes.

“Today, a wide range of computerized diabetes devices are available to help people better manage their blood sugar levels while research toward a cure for diabetes marches forward,” Saenz says. Advances in technology include continuous glucose monitors, smart insulin pens, combination CGM-insulin pumps, and even mobile apps.

But it’s still important to use the technology correctly and remain compliant with the diabetes care plan that your healthcare team helps you develop. The complications from diabetes are very real, but tight management of your blood sugar levels can help you avoid them longer.