Type 1 vs. Type 2 diabetes: What’s the difference?

Type 1 vs. Type 2 diabetes causes | Prevalence | Symptoms | Diagnosis | Treatments | Risk factors | Prevention | When to see a doctor | FAQs | Resources

Approximately 1 in 10 people have diabetes, according to the CDC. In 2018, there were 34.2 million Americans diagnosed with diabetes, which is 10.5% of the population. There are four types of diabetes: prediabetes, Type 1, Type 2, and gestational diabetes. Those with prediabetes or gestational diabetes (diabetes during pregnancy) are at risk for developing Type 2 diabetes. Type 2 diabetes is much more common than Type 1, but it’s important to know the difference if you’re at a higher risk of developing any type of diabetes. In this article, we will discuss the difference and similarities between Type 1 vs. Type 2 diabetes.

Causes

Type 1 diabetes

The human body requires insulin, which is made in the pancreas. Insulin helps the cells receive blood sugar and use it for energy. When there is no insulin, the blood sugar stays in the bloodstream rather than going into the cells, leading to high blood sugar levels and causing serious health complications and damage to the body.

“Type 1 diabetes occurs when people don’t produce enough insulin; it occurs due to the destruction of the insulin-producing pancreatic beta-cell,” explained Sunitha Posina, MD, an NYC-based board-certified internist. “Most of the cases are autoimmune, which means your body attacks and destroys the pancreatic cells that produce insulin and therefore you won’t make as much insulin.”

Why does the body attack its own cells? Researchers still aren’t quite sure at this time. A trigger, such as exposure to a virus, could cause the attack on the body’s cells, which then leads to the development of Type 1 diabetes. 

Type 2 diabetes

Insulin is also the culprit in the case of Type 2 diabetes. However, in Type 2 diabetes, cells don’t respond correctly to insulin, which causes insulin resistance. The pancreas will still produce insulin, however, it will not make enough insulin or the body will not use it effectively. Therefore, blood glucose levels rise. The early stages of insulin resistance are called prediabetes and can eventually turn into Type 2 diabetes.

High blood sugar is a very serious problem. It damages the body and can create other health issues, including heart disease, kidney disease, or vision loss. 

It is unclear when some people have insulin resistance, but researchers believe that genetic factors, environmental factors, and lifestyle factors (including excess weight and little exercise) can contribute.

Type 2 diabetes is most common in adults, so much so that it was once called adult-onset diabetes. However, now Type 2 diabetes is diagnosed in some children. It has also been called “non-insulin-dependent diabetes,” which is also inaccurate as some patients may require insulin at some point for the management of their diabetes. 

Prevalence

Type 1 diabetes

Out of the 34 million adults with diabetes, only 5%-10% of these people have Type 1 diabetes, making it less common than Type 2 diabetes. An estimated 187,000 children and adolescents younger than 20 years of age were living with Type 1 diabetes in 2015.

Type 2 diabetes

The most common form of diabetes is Type 2 diabetes, with 90% to 95% of the 34 million adults having Type 2 diabetes. The prevalence of diabetes increases with age. Men and women have approximately the same prevalence rate, but the incidence is higher in American Indians and Alaskan Natives. Black and Hispanic populations also have a higher prevalence of diabetes than non-Hispanic whites.

RELATED: Diabetes statistics

Symptoms

Some symptoms overlap between Type 1 and Type 2 diabetes. These symptoms include: 

• Frequent urination, especially at night
• Extreme thirst or hunger
• Unexplained weight loss
• Blurry vision
• Fatigue
• Dry skin
• Slow-healing wounds
• More frequent infections due to a lowered immune system 

Type 1 diabetes

Type 1 diabetes symptoms often take a few weeks or months to show and can start at any age. Type 1 diabetes has the symptoms listed above in addition to stomach pains, nausea, or vomiting. Symptoms can be severe even during the early stages. If you notice symptoms, seek medical advice right away as these health problems can be fatal.

Type 2 diabetes

The symptoms of Type 2 diabetes include all those listed above as well as tingling or numbness in hands or feet. These symptoms develop over time, so it may take a longer time to notice them. Other times, symptoms may go unnoticed. Due to this, it is vital to regularly get your blood sugar tested if you have any of the risk factors: overweight, family members with Type 2 diabetes, older than 45 years of age, or inactiveness. 

Diagnosis

Type 1 diabetes

There are different tests that healthcare providers will perform if Type 1 diabetes is suspected. One will test for autoantibodies, which indicates if the body is attacking itself. These autoantibodies are present in Type 1 diabetes but not Type 2. Ketones in your urine will also be tested.

Type 2 diabetes

There are four possible tests your doctor may perform to check your blood sugar levels. They include the following:

• A1C test: This test measures the average of your blood sugar for the past two to three months. Tests under 5.7% are normal, 5.7%-6.4% is an indicator of prediabetes, and 6.5% or higher indicates diabetes.
• Fasting blood sugar test: For this blood test, you will fast (not eat) starting the night before. For those without diabetes, a normal blood sugar level will be 99 mg/dL or lower. A range of 100 to 125 mg/dL is standard in those with prediabetes, and high blood glucose levels of 126 mg/dL or more indicate a diagnosis of diabetes. 
• Glucose tolerance test: For the glucose tolerance test, you also fast by not eating the night before. You will then have your blood drawn to see the rate of your fasting blood sugar. Next, you will drink a sugary glucose liquid, and your blood sugar levels will be checked every hour for up to three hours. At two hours, normal blood sugar is 140 mg/dL or lower, 140 to 199 mg/dL indicates prediabetes, and a higher level will indicate diabetes. 
• Random blood sugar test: A random blood sugar test can be taken at any time and does not require fasting. If your blood sugar levels are higher than 200 mg/dL, this indicates diabetes.

“We most commonly use the A1C these days or fasting blood sugar test to diagnose diabetes,” Dr. Posina says.

Treatments

Type 1 diabetes

Those with Type 1 diabetes do not produce any insulin, so they require insulin injections or an insulin pump that manages their blood sugar levels every day. A healthcare provider will guide you to determine the correct levels of insulin you need. Insulin therapy helps maintain a normal blood sugar level around 80-130 mg/dL unless you’ve been eating, and then normal levels can be up to 180 mg/dL for up to two hours after.

In addition to using insulin to regulate blood sugar, those with Type 1 diabetes will need to have a healthy diet and monitor the carbohydrate, fat, and protein intake. Maintaining a healthy weight and exercising will also help improve the outcomes of those with Type 1 diabetes. 

A promising device for those managing Type 1 diabetes is the artificial pancreas. Approved by the Food and Drug Administration (FDA) in September 2016, this device automatically checks blood sugar levels frequently and delivers insulin as needed. 

Type 2 diabetes

The most significant part of Type 2 diabetes treatment is making healthy lifestyle changes. Changes include weight loss, eating a healthy diet, and exercising regularly. Weight loss of 5% to 10% of a person’s body weight can lower blood sugar levels. A healthy diet with plenty of vegetables, fruits, and fiber with fewer foods high in carbs and saturated fats can also help regulate blood sugar levels. Frequent exercise will also be vital as it naturally lowers blood sugar. Other lifestyle changes may include managing stress and getting enough sleep.

Blood sugar monitoring and medications are other critical components of Type 2 diabetes management. The frequency of blood sugar monitoring varies by person and depends on their treatment plan. If a person with Type 2 diabetes is insulin-dependent, they will need to check their blood sugar multiple times a day. While some people can manage diabetes with diet and exercise alone, others may require medication and insulin therapy. 

Medications may include:

• The American Diabetes Association recommends metformin as the preferred therapy for the treatment of Type 2 diabetes. Metformin is a generic drug used together with diet and exercise to improve blood sugar control in adults with Type 2 diabetes mellitus. It goes by the brand names Glucophage, Riomet, Glumetza, and Fortamet. It works by lowering glucose production in the liver and improving the body’s ability to use insulin. 
• DPP-4 inhibitors, including Tradjenta (linagliptin) or Januvia (sitagliptin), work by lowering blood sugar levels. 
• GLP-1 receptor agonists are typically used for patients that are unable to tolerate or use metformin. They are injectable medicines that help decrease blood sugar levels. GLP-1 receptor agonists include Victoza (liraglutide) and Ozempic (semaglutide).
• Meglitinides reduce the number of simple sugars (glucose) in the bloodstream by increasing insulin production by the pancreas.  Some common medications in this category include repaglinide and Starlix (nateglinide).
• SGLT2 inhibitors lower the blood sugar by using the kidneys to remove sugar in the body through the urine. Two common SGLT2 inhibitors include Farxiga (dapagliflozin) and Jardiance (empagliflozin).
• Sulfonylureas are a class of drugs that cause your body to secrete more insulin. Examples include Glynase (glyburide) and Glucotrol (glipizide).
• Thiazolidinediones (TZD) also reduce the body’s resistance to insulin. Common medications include  Avandia (rosiglitazone) and Actos (pioglitazone).
• Blood pressure medication is also common in treating diabetes, as 2 in 3 people with diabetes also have high blood pressure.

RELATED: Diabetes medications and treatments

Risk factors

Type 1 diabetes

Risk factors are not as clear cut for Type 1 diabetes. However, there are few known risk factors. 

• Family history: There is a slightly higher risk of developing Type 1 diabetes if your sister, brother, or parents have Type 1 diabetes. 
• Age: Type 1 diabetes can happen at any age, but it is most commonly diagnosed in children and young adults. Due to this, it has previously been called juvenile diabetes or juvenile-onset diabetes. 
• Race: White people have Type 1 diabetes more commonly than Black Americans and Latino Americans. 

Type 2 diabetes

Individuals who have the highest risk for Type 2 diabetes include:

• Prediabetes: Those diagnosed with prediabetes have a higher likelihood of developing diabetes. 
• Weight: Those who are overweight have a higher risk than those with a healthy BMI.
• Age: Individuals 45 years and older are more commonly diagnosed with Type 2 diabetes.
• Family history: There is a higher risk of developing Type 2 diabetes if your sister, brother, or parents have Type 2 diabetes. 
• Inactivity: Exercising less than three times a week is a known factor.
• Gestational diabetes: There is a higher risk of developing Type 2 diabetes if a woman has gestational diabetes or has a baby who weighed nine or more pounds at birth.
• Race: Certain races are at higher risk, including Black Americans, Hispanic/Latino Americans, American Indians, and Alaska Natives

Prevention

Type 1 diabetes 

Unfortunately, there is no known prevention for Type 1 diabetes at this time. 

Type 2 diabetes

Making healthy lifestyle changes can delay the onset of Type 2 diabetes, prevent it, or even reverse it in some cases. Prevention includes losing weight if you’re overweight, exercising regularly, and adopting a healthy eating pattern. 

When to see a doctor for Type 1 or Type 2 diabetes

If you have any symptoms of diabetes, you should visit a healthcare provider immediately as symptoms can be severe and life-threatening. You should also have regular check-ups with your healthcare provider to monitor the progress of your diabetes care.

Frequently asked questions about diabetes

Which is worse: Type 1 or Type 2 diabetes?

Type 1 and Type 2 diabetes can have serious health consequences if not properly managed. Each person is different and unique, so it is impossible to say which one is worse.

RELATED: Diabetes survey shows symptoms lower quality of life in 1 in 5 patients

Can Type 2 diabetes become Type 1?

No, Type 1 and Type 2 diabetes have different causes. However, because they share similar symptoms, misdiagnosis is possible.

Does Type 1 or Type 2 diabetes need insulin?

People with Type 1 diabetes are considered to have insulin-dependent diabetes as they will always require insulin to manage their blood sugar levels. Some people with Type 2 diabetes are dependent on insulin, but others manage it by following a healthy lifestyle and using medication without insulin. 

Can Type 1 diabetes be reversed?

Since those with Type 1 diabetes cannot produce insulin, there is currently no way to reverse it. 

What foods are bad for people with diabetes?

Sugars and carbohydrates, which break down into sugars, should be avoided and eaten in moderation as it could cause spikes in blood sugar. These spikes can lead to health complications.

Resources

• Artificial pancreas improves Type 1 diabetes management, National Institutes of Health

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