Type 1 diabetes (T1D) basics

T1D occurs when your immune system attacks and destroys the insulin-producing beta cells of the pancreas. As the body becomes incapable of creating insulin, T1D symptoms start to appear, such as extreme thirst, frequent urination, weight loss, and fatigue.


Learn more about T1D onset factors.

Type 1 diabetes doesn’t discriminate. It affects people of all races, ethnicities, ages, and socioeconomic backgrounds. 

Although the exact causes of T1D are unknown, researchers have discovered possible genetic and environmental factors that may lead to a higher likelihood of developing the condition.
 

Learn more about the biology of T1D. 

A type 1 diabetes diagnosis can happen suddenly and unexpectedly. T1D onset symptoms often include thirst, frequent urination, weight loss, and fatigue. Physicians must be quick to spot the telltale signs and symptoms of T1D. Tools used to determine a positive T1D diagnosis include blood- glucose tests, an HbA1C test, and a ketone test. 

Learn more about how type 1 diabetes is diagnosed.
 

Diabetes is a disease that disrupts the body’s ability to regulate glucose levels. Though they share some similarities, type 1 diabetes and type 2 diabetes have different causes, effects, and treatments. 

Type 1 diabetes (T1D) is an autoimmune condition that is not preventable. In T1D, the body destroys the cells that produce insulin, a hormone that everyone needs to get energy from the food they eat. T1D is the less common form of diabetes. 

Type 2 diabetes is a metabolic disease in which the body makes insulin but does not use it properly. T2D is the most common type of diabetes. 

Learn more about the differences between type 1 diabetes and type 2 diabetes. 

Yes, type 1 diabetes (T1D) is also referred to as type 1 diabetes mellitus, insulin-dependent diabetes mellitus, autoimmune diabetes, and juvenile diabetes. Juvenile diabetes is considered an outdated term as we now know that T1D onset can occur at any age

Insulin is a hormone produced by beta cells in the pancreas that helps regulate blood-sugar levels. 

Your body breaks down the food you eat into glucose and releases it into your bloodstream. Insulin is the “key” that unlocks the cells in your body to allow that glucose to enter and be used for energy. Without insulin, or enough insulin, glucose levels in your blood rise.  

People living with T1D don’t produce insulin. Therefore, they must rely on insulin therapy to manage their blood-glucose levels. 

Learn more about insulin. 

Hypoglycemia is the medical term for low blood sugar (low blood glucose). Your body, especially your brain, depends on glucose to work. Too little sugar in your blood causes problems that can sometimes be serious.
Symptoms of low blood sugar include: 

  • Feeling sweaty, shaky, or hungry 
  • Dizziness 
  • Having trouble seeing clearly 
  • Getting disoriented 

To treat mild to moderate hypoglycemia, you must ingest glucose in the form of rapid-acting carbohydrates. When hypoglycemia is severe, emergency glucagon may be needed.
 

Hyperglycemia is the medical term for high blood sugar (high blood glucose). It happens when your body has too little insulin to move the sugar in your blood into the cells.
To treat hyperglycemia, you must administer insulin.
Symptoms of high blood sugar include: 

  • Being extremely thirsty 
  • Urinating (peeing) a lot 
  • Feeling very tired 
  • Having trouble seeing or concentrating 
  • Having sweet-smelling or “fruity” breath 

Prolonged hyperglycemia can lead to the production of ketones and risk for a life-threatening condition called diabetic ketoacidosis, or DKA.
 

Ketones are caused by the breakdown of fat when there isn’t enough insulin to allow the glucose (sugar) into your cells for energy. When ketones build up, the result is acidosis (too much acid in the blood). Diabetic ketoacidosis (DKA) is a serious condition in which an insulin-deprived body seeks energy from stored fat. DKA requires immediate medical attention.

Managing type 1 diabetes

Type 1 diabetes is a condition that requires 24/7 management. But thanks to advancements in medication types and delivery methods, people with T1D can live long, happy lives with access to medication and devices and proper care and disease management.


Get more information on staying healthy while living with type 1 diabetes.

Type 1 diabetes is managed through use of insulin. People with T1D must work closely with their medical team to find the right insulin type and treatment for their condition. Treatment for T1D also includes monitoring and other lifestyle accommodations in addition to insulin. Blood-sugar monitoring, carbohydrate counting, exercise and diet, and regular medical checkups are all essential to successfully manage T1D.


Learn more about managing T1D.

When someone has a chronic diagnosis, it often affects their mental and emotional health. It can affect other family members, too. Some people experience “diabetes distress” and others may experience more significant challenges.  

If you or your loved one is experiencing signs of diabetes distress, talk to your healthcare provider about whether it could be time to seek help from a mental health professional. 

There are many types of insulin. These include ultra-rapid, rapid, regular, intermediate-acting, long-acting, and ultra-long acting. Insulin can be injected or inhaled.

Learn more about insulin types.

Insulin is administered via injection, insulin pump, inhaler, or artificial pancreas system/automated insulin delivery system.

Learn more about insulin delivery methods.

Multiple daily injections, or MDI, are the most common way of treating T1D outside of the U.S. Every person with T1D using MDI needs two types of insulin: basal (background) long-acting insulin, and mealtime/prandial rapid-acting insulin (given with meals or to correct high blood sugar). These insulins can be administered via a vial and syringe or insulin pen. 

Insulin pumps are small, wearable devices individually programmed to deliver insulin into the body at numerous intervals throughout the day and night. They are used in place of multiple daily injections (MDI) of insulin.
Insulin pumps release a low, steady flow of insulin (basal insulin) 24 hours a day, as well as extra doses of insulin (boluses) to accommodate rises in blood sugar as needed (e.g., when one eats).

Learn more about insulin pumps.

Continuous Glucose Monitors (CGMs) are small, wearable devices that continuously measure a person’s blood-glucose levels. They are used in place of traditional glucose meters that require finger sticks.
A sensor just under the skin measures the interstitial-glucose levels in real time. The levels are then relayed to a receiver, smartphone or watch, or insulin pump, which displays the readings. CGMs can be worn on different parts of the body depending on the manufacturer.   

Learn more about CGMs.

Time-in-range (TIR) is a measurement that tells you what percentage of the day your blood sugars are in your goal range. Today, the measure of TIR has become a potentially more valuable method of assessing blood-sugar management thanks to the development of continuous glucose monitors (CGM). 

You should work with your healthcare team to determine the appropriate goal range for your blood- sugar levels. TIR tells you how often you’re actually within that goal range.


An automated insulin delivery system has three main components: an insulin pump, a continuous glucose monitor (CGM), and an algorithm (the math that determines the best insulin dose to help keep you in range). These systems measure glucose and adjust insulin when you are not eating, giving less insulin when blood sugar is low and more insulin when blood sugar is high. The person wearing the device still needs to intervene during meals and intense exercise. 

Learn more about automated insulin delivery systems. 

Type 1 diabetes healthcare coverage and costs

The Breakthrough T1D Health Insurance Guide has information about health insurance and T1D, as well as programs that may help you reduce out-of-pocket costs. 

Visit our Health Insurance Guide.

It can be frustrating and sometimes scary if you’re not able to fill a prescription or continue a treatment—or face paying the full cost of your treatment. The good news is you have the right to appeal the decision. And, while it can be time-consuming to deal with, many health insurance denials may be resolved through the insurance appeals process. 

Visit our Health Insurance Guide to learn how to file an appeal with your health insurance copmpany.

A prior authorization is a requirement from your health insurance company that your doctor obtains approval from your plan before it will cover the costs of a specific medicine, medical device, or procedure. Many times, this involves your doctor completing a form to illustrate to your insurance company why the insulin, insulin pump, or continuous glucose monitor (CGM) you are prescribed is medically necessary. 

Visit our Health Insurance Guide to learn more about prior authorizations.

Prescription costs for drugs to treat type 1 diabetes (T1D) can make up a large percentage of what you pay each year for healthcare. There are a few ways you can lower your prescription and insulin costs: through state and nonprofit programs; diabetes patient assistance programs offered by pharmaceutical companies; medication discount cards; and prescription alternatives such as biosimilar insulin. 

Learn more about getting help with your diabetes prescription and insulin costs.

Type 1 diabetes and lifestyle

No! That is a common misconception about T1D. T1D is an autoimmune disease.

Learn more about what causes T1D.

Yes. But having type 1 diabetes means that in addition to consuming responsibly, you will also need to understand the effect of alcohol on blood sugar and keep an eye on it while drinking. 

Moderate amounts of alcohol may cause blood sugar to rise, but excess alcohol can actually decrease your blood- sugar level, which can be dangerous for people with T1D. Emergency glucagon is not effective after heavy drinking.  

People with T1D can eat anything other people can eat, and everyone should eat a healthy, balanced diet. 

People living with type 1 diabetes (T1D) can and should experience the benefits of sports and exercise. Physical activity is great for your body and has positive effects on your mind—and T1D should not prevent anyone from reaping the benefits. Exercising with T1D does require extra preparation, but by following some guidelines, everyone can incorporate sports and exercise into their life.  

When a person gets sick, their body is under stress. To combat that stress, the body naturally releases hormones that help fight off illness. Those hormones, however, cause blood- glucose levels in the body to rise and disrupt the way insulin lowers blood- glucose levels, increasing the risk of hyperglycemia (high blood sugars).  

With T1D, it’s essential to work with your healthcare provider to develop a plan of action in place for illness. This includes: 

  • Carefully monitoring your blood sugar 
  • Checking for ketones, especially when appetite is diminished or with vomiting illnesses 
  • Increasing hydration 
  • Having contact information for your healthcare provider readily available 

The most important advice for a traveler with type 1 diabetes is to be prepared! 

  • Pack roughly twice as many supplies as you think you will need. 
  • Be sure to have cooling packs for insulin storage. 
  • Check with your health insurance to ensure you have coverage at your destination. 
  • Wear a medical ID bracelet and always keep your emergency contact information with you. 
  • Consider buying travel insurance, especially for international travel. 
  • If flying, keep your diabetes-related supplies, equipment, and medication with you in a carry-on bag. Insulin in a checked bag can freeze or get damaged.

Consult the TSA guidelines for travelers with medical conditions.

Pregnancy with type 1 diabetes can directly impact the health of the child and the mother. Having T1D well-managed pre-conception is key to a safe and healthy pregnancy. 

You should also create a pregnancy plan. Many women choose to work with a team that includes an endocrinologist, primary care doctor, and an OB-GYN, preferably one who has experience with T1D pregnancies. 

Most experts recommend having an HbA1c at or below 6 percent before you conceive and maintaining that range throughout your pregnancy. It’s also important early in the planning/pre-conception stages to consider wearing a continuous glucose monitor (CGM) to help you maintain healthy blood-glucose levels. 

Learn more about pregnancy and type 1 diabetes.

Type 1 diabetes at school

T1D does not stop children, teens, and young adults from enjoying and taking part in all school and extracurricular activities. But school can sometimes be overwhelming for students living with T1D, as well as their parents and caregivers. It is important for teachers, school nurses, and educators to be aware of T1D so they can ensure the safety and well-being of the student.
 

A 504 Plan is a legal, written document specifying what “reasonable” modifications and accommodations the school must provide for a student with a disability. 504 Plans are a way for you to hold the school accountable for meeting your child’s needs while in the school’s care.
 

The transition from high school to living independently with type 1 diabetes will bring a lot of new learning experiences, challenges to overcome, and adventures. Creating a diabetes management plan allows your child to have a system in place to aid in managing their T1D no matter what new or stressful situations they encounter.

Type 1 diabetes outcomes

We don’t have cures that restore insulin independence for people with T1D yet, but we know what must be done to make them a reality. To find cures for T1D, we need to: 

  1. Restore or replace insulin production 
  1. Turn off the autoimmune attack responsible for destroying the insulin-producing beta cells 

To accomplish that, Breakthrough T1D’s cures portfolio is focused on three areas: 

  1. Global Universal Early Detection
    There’s a simple blood test that can detect T1D autoantibodies, proteins in the blood that show an active immune attack is underway.  

    Early detection has been directly linked to a reduction in diabetic ketoacidosis (DKA) at T1D diagnosis. Ensuring more people have access to early detection can have a transformative effect on the landscape of T1D research by speeding up clinical trials and save lives at the same time.  
    Learn more about the important role early detection plays in achieving a world without T1D. 
  1. Disease-Modifying Therapies 
    T1D is a progression. There are people whose immune system has begun attacking the insulin-producing beta cells, but they are not symptomatic yet. There are also people who have had T1D for decades and have lost nearly all insulin production. Disease-modifying therapies (DMTs) are a way to intervene and slow or stop the attack.  
  1. Cell Therapies 
    Many people with T1D have no insulin-producing cells left. Breakthrough T1D invests in research and clinical trials to develop healthy, insulin-producing cells, insert them into the bodies of people with T1D, and protect them while in the body with minimal or no immunosuppression. 

Having T1D can increase your risk for related complications. The longer you have T1D, the higher your risk becomes for developing complications like kidney disease, eye disease, and cardiovascular disease. Keeping your glucose levels in the target range can help delay complications.

Learn more about daily management of T1D for better health outcomes.

Currently, T1D cannot be reversed in individuals already diagnosed. T1D also cannot be prevented. But, thanks to funded research in disease-modifying therapies, T1D can be delayed in individuals who are identified in the early stages of T1D through early detection.

Learn more about early detection for T1D. 

People who have a family member with T1D are up to 15x more likely to develop the disease. Current clinical guidelines recommend T1D early detection through research or as part of a clinical trial. However, about 85% of T1D diagnoses happen to people with no known family connection, which is why Breakthrough T1D has a long-term goal of global universal T1D early detection. 

Learn more about early detection for T1D.

Participating in a clinical trial is a great way to contribute to T1D cures and improving lives! Currently, there are approximately 300 clinical trials underway to prevent, cure, and treat T1D and its complications. Breakthrough T1D has an easy-to-use tool to match you with clinical trials for which you are eligible. 

Find a clinical trial now.

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