Type 1 Diabetes

Overview

Type 1 diabetes (referred to in the past as juvenile diabetes) is a chronic health condition in which the body's immune system destroys the cells in the pancreas that produce insulin. Insulin is needed to convert sugar (also called glucose) from food into energy for most of the body’s cells. Without insulin, people experience dangerously high blood sugar levels (called hyperglycemia). To manage blood sugar levels, people with type 1 diabetes must take insulin injections, receive insulin through a device, or even inhale insulin. Read our resource page to learn more about the symptoms, complications, and various treatment options for type 1 diabetes.

Can type 1 diabetes be prevented?

Although researchers have made progress in recent years, there is currently no way to prevent type 1 diabetes. Current research focuses on restoring or replacing insulin production through stem cell therapy, stopping the autoimmune destruction of your body’s insulin-producing cells, and delaying the onset of type 1 diabetes. However, identifying those at risk is not easy. The genetic and environmental triggers for diabetes are not well understood, and 80% of people with the condition do not have a family history of type 1 diabetes.

Will I get type 1 diabetes if it runs in my family?

People who have family members with type 1 diabetes have an increased risk to develop it themselves. If an immediate relative (parent, sibling, or child) has type 1 diabetes, that person’s risk of developing the condition is much greater than the risk of the general population (normally a 1% risk). Depending on whether a father or mother has type 1 diabetes, and when they developed the condition, the risk of a child developing type 1 diabetes can range from an increase of 1% to 12%, or 10% to 25% if both parents have diabetes.

If someone in your family has type 1 diabetes, talk with your healthcare team about screening for the other family members. Discovering an increased risk for diabetes is helpful to reduce the chances of dangerous health complications at the time of onset.

What are the symptoms of type 1 diabetes?

Signs of Hyperglycemia

Increased thirst
Frequent urination
Extreme hunger
Unexplained weight loss
Presence of ketones in the urine (ketones increase in the body when there's not enough available insulin)
Fatigue
Irritability
Blurred vision
Slow-healing sores
Frequent infections (including gums, skin, and vaginal infections)

Signs of Hypoglycemia

Hunger
Sweating
Shaking
Fast heartbeat
Headache
Trouble concentrating
Fatigue
Irritability
Confusion

Severe Hypoglycemia

During severe hypoglycemia you may experience different symptoms that indicate that your brain doesn’t have enough glucose to properly function.

Signs of Severe Hypoglycemia

Confusion
Combativeness
Disorientation
Seizures
Loss of consciousness

How is type 1 diabetes diagnosed?

Type 1 diabetes can be diagnosed through any of the following tests:

An A1C test, also called a glycated hemoglobin test or HbA1c test. This blood test provides an estimate of a person’s average blood sugar level from the past two or three months. An A1C of 6.5% or higher is considered diabetes. (5.7% to 6.4% is considered prediabetes, and an A1C below 5.7% is considered normal.)
A fasting plasma glucose (FPG) test measures a person’s blood glucose level after fasting for eight hours. An FPG of 126 mg/dl or higher indicates diabetes.
An oral glucose tolerance test (OGTT) measures the body's blood glucose level two hours after consuming a sugary drink. An OGTT result at two hours of 200 mg/dl or higher indicates diabetes.
In someone with symptoms of high blood sugar (or hyperglycemia), a random plasma glucose test can be used to check blood sugar levels. A random blood sugar level above 200 mg/dl indicates diabetes.

How is insulin used to treat type 1 diabetes?

People with type 1 diabetes almost always take insulin daily to help manage their blood sugar levels. There are two main types of insulin: basal insulin and bolus (or rapid acting) insulin. Basal insulin, typically taken once per day, provides a constant, low level of insulin. Basal insulin helps keep blood sugars consistent when one is not eating, but it doesn’t cover glucose spikes after mealtime. Rapid acting insulin, on the other hand, is given before meals.

Some people with type 1 diabetes also take other medications. For an overview of diabetes drugs, please see diaTribe’s diabetes drugs resource page.

How can continuous glucose monitors help people with type 1 diabetes?

CGM devices track glucose levels every few minutes throughout the day and night, providing useful information for staying in your target blood glucose range (70-180 mg/dl). In 2017, about 31% of adults with type 1 diabetes in the US used continuous glucose monitors (CGM), and this number has been increasing dramatically – in 2021, the T1D Exchange reported that more than 80% of their participants used CGM.

What is hypoglycemia?

Hypoglycemia refers to low blood sugar levels. A blood sugar level below 70 mg/dl (3.9 mmol/L) is typically considered hypoglycemia, and you will likely experience symptoms when your blood sugar dips this low – especially if it drops below 54 mg/dl (3.0 mmol/L).

Symptoms of hypoglycemia include confusion, headache, irritability, trouble concentrating, fatigue, hunger, sweating, shaking, and fast heartbeat. Symptoms of severe hypoglycemia may include combativeness, disorientation, seizures, difficulty speaking, loss of consciousness, or coma.

To raise blood sugar levels, you could eat or drink a specific amount of fast-acting carbohydrates. If the person cannot eat or drink, emergency glucagon can be administered either as an injection or nasal spray. Immediate medical attention may also be required.

What is hyperglycemia?

Hyperglycemia refers to high blood sugar levels. A blood glucose level of 180 mg/dl (10 mmol/l) or higher is considered hyperglycemia and can result in acute symptoms, especially if more than 250 mg/dl (13.9 mmol/L). Over a long period of time, hyperglycemia may lead to complications.

Symptoms for hyperglycemia are sometimes subtle, but if present, they include frequent and excessive urination and increased thirst, weight loss, blurry vision, confusion, and headache.

What is diabetic ketoacidosis?

Diabetic ketoacidosis (DKA) is a condition that can occur with diabetes and usually is associated with hyperglycemia. DKA can occur when the body breaks down fatty acids for energy in an uncontrolled manner, and the blood becomes acidic. Symptoms of DKA include nausea and vomiting, abdominal pain, shortness of breath, fruity-smelling breath, confusion, and loss of consciousness. If someone with type 1 diabetes is showing any signs of DKA, that person should immediately measure blood ketones levels and seek medical attention.

What complications are associated with type 1 diabetes?

Having diabetes increases a person’s risk of developing long-term health complications. Over time, the high blood sugar levels that are associated with diabetes can damage the body, affecting the nerves, eyes, kidneys, blood vessels, and heart. Maintaining blood glucose levels in a healthy range can help reduce a person’s risk for complications. To read more about complications, click here.

How does type 1 diabetes affect life expectancy?

If blood glucose levels are not well controlled, diabetes over time can challenge the body and affect life expectancy. However, research has shown someone with well-controlled diabetes should have the same life expectancy as that of the general population.

The Basics

Drugs and Devices

Nutrition and Food

Physical Activity

Extra Info

*Please note, this page is not a comprehensive list of all the available resources.