What Is Type 1 Diabetes?

Type 1 diabetes is a chronic condition in which the pancreas stops producing enough insulin. The pancreas is an organ behind the stomach that helps convert food into fuel. Insulin is a hormone that allows glucose (sugar) to move from the blood into the cells for energy.

Without enough insulin, glucose builds up in the bloodstream. High blood sugar can damage the heart, blood vessels, nerves, kidneys, eyes, feet, and skin. Extremely high levels may lead to diabetic ketoacidosis (DKA), a life-threatening condition where the blood becomes acidic.

Type 1 diabetes is one form of diabetes mellitus, accounting for about 5% of all diabetes cases. Its exact cause is unknown, but researchers believe a combination of genetic and environmental factors contributes to the condition.

Previously called juvenile diabetes, type 1 diabetes is common in children and teens but can also occur in adults. Symptoms include excessive thirst, fatigue, weakness, and unexplained weight loss.

There is currently no cure, but the condition can be managed with insulin therapy and a healthy lifestyle.

Types of Type 1 Diabetes

There are three subtypes of type 1 diabetes:

Acute-Onset Type 1 Diabetes (AT1D)

This is the most common form. Symptoms appear suddenly, often due to diabetic ketoacidosis (DKA), a complication that happens when the liver produces too many ketones because of insulin deficiency. People with AT1D typically experience symptoms like excessive thirst, frequent urination, and weight loss within three months.

Slowly Progressive Type 1 Diabetes (SP1D)

SP1D develops gradually. It is caused by antibodies that slowly destroy the insulin-producing cells in the pancreas. It can affect both children and adults, but because symptoms take longer to appear, it's often diagnosed later in life.

Fulminant Type 1 Diabetes (FT1D)

This rare form progresses very rapidly. The immune system suddenly and aggressively destroys insulin-producing cells. It can be difficult to manage and may become fatal if left untreated.

Symptoms

When the pancreas produces little or no insulin, symptoms can appear quickly. Common signs include:

• Frequent urination: High sugar levels cause the kidneys to flush out excess sugar, leading to increased urination, including nighttime urination or bed-wetting in children.

• Excessive thirst: Dehydration from frequent urination can cause constant thirst.

• Increased hunger: When sugar cannot enter cells for energy, you may feel hungry despite eating.

• Unintended weight loss: The body uses fat and muscle for energy when it cannot access glucose.

• Fatigue: Lack of cellular energy leads to persistent tiredness.

• Tingling or numbness in limbs: High blood sugar can damage nerves.

• Slow-healing sores or infections: A weakened immune system reduces healing ability.

• Blurry vision: Damage to the small blood vessels in the eyes may affect sight.

Symptoms of diabetic ketoacidosis (DKA) include:

• Trouble breathing

• Flushed, dry skin

• Fruity-smelling breath

• Nausea or vomiting

• Stomach pain or cramps

DKA is a medical emergency. Call for immediate help if these symptoms occur.

Causes

Type 1 diabetes is an autoimmune condition where the body mistakenly attacks healthy pancreatic cells that produce insulin. This autoimmune reaction may be triggered by genetics or environmental factors.

Risk factors include:

• Family history of type 1 diabetes

• Specific genes like HLA-DR

• Certain infections

• Stress

• Cold climates

• Lack of breastfeeding during infancy

Diagnosis

Healthcare providers use several tests to diagnose diabetes:

• A1C Test: Measures average blood sugar over the past 3 months. A result of 6.5% or higher suggests diabetes.

• Fasting Plasma Glucose (FPG) Test: After at least 8 hours of fasting, a level of 126 mg/dL or higher confirms diabetes.

• Oral Glucose Tolerance Test (OGTT): After drinking a sugary liquid, blood sugar levels are measured over 2 hours. A result of 200 mg/dL or higher indicates diabetes.

• Random Glucose Test: Measures blood sugar at any time. A level of 200 mg/dL or more may suggest diabetes.

• Glucose Challenge Test: Common in pregnancy. A follow-up OGTT confirms diagnosis if levels are high.

To confirm type 1 diabetes, providers also test for autoantibodies that target insulin-producing cells, such as:

• Insulin autoantibodies (IAA)

• Insulinoma-associated-2 autoantibodies (IA-2A)

• Islet cell cytoplasmic autoantibodies (ICA)

• Glutamic acid decarboxylase autoantibodies (GADA)

Stages of Type 1 Diabetes

• Stage 1: No symptoms yet, but two or more autoantibodies are detected. Blood sugar remains normal.

• Stage 2: Still no symptoms, but blood sugar is no longer normal. Two or more autoantibodies are present.

• Stage 3: Symptoms appear. Blood sugar is high, and multiple autoantibodies are confirmed. This is the clinical diagnosis stage.

Treatment

There is no cure for type 1 diabetes, but treatment focuses on managing blood sugar levels to prevent complications.

Management includes:

• Insulin therapy: Since the pancreas no longer produces insulin, patients must take it daily via injections, insulin pens, or insulin pumps.

• Blood sugar monitoring: Regular checks are necessary to maintain healthy glucose levels.

• Technology support: Continuous glucose monitors (CGMs) can track blood sugar and connect to insulin pumps.

A diabetes care team may include:

Prevention

In 2022, the FDA approved Tzield, the first drug to delay type 1 diabetes onset in high-risk individuals. Administered by injection, Tzield helped delay diagnosis by an average of over four years in clinical trials. It is approved for people aged 8 and older with increased risk.

Although there is no full prevention method, ongoing research is exploring new ways to protect insulin-producing beta cells.

Additionally, managing blood sugar with a healthy lifestyle can prevent further damage. Daily insulin, regular monitoring, nutritious food, physical activity, and rest all support diabetes control.

Living With Type 1 Diabetes

Living with this condition can be difficult, but proper care and support can help maintain a high quality of life. Key lifestyle strategies include:

• Managing stress: Stress raises blood sugar levels. Meditation, journaling, or spending time with others can help.

• Eating a healthy diet: Focus on vegetables, fruits, lean proteins, healthy fats, and complex carbs.

• Exercising regularly: Physical activity helps regulate blood sugar by using it for energy.

• Getting enough sleep: Proper rest supports stable blood sugar levels.

• Staying connected: Talking with family, friends, or others with diabetes can reduce stress and provide emotional support.

Quick Summary

Type 1 diabetes is caused by a lack of insulin production due to the immune system attacking the pancreas. It can lead to high blood sugar and related symptoms like thirst, hunger, fatigue, and weight loss.

Early diagnosis and treatment are crucial. Insulin therapy, regular monitoring, and healthy lifestyle changes can help manage the condition and prevent complications. Though there is no cure, with the right care, people with type 1 diabetes can live full and active lives.