What is type 1 diabetes?

Type 1 diabetes (T1D) is an autoimmune disease that occurs when the body’s own immune system mistakenly destroys insulin-producing cells in the pancreas. Without insulin, cells throughout the body cannot take up energy from glucose, which leads to health complications such as high blood sugar (hyperglycemia), low blood sugar (hypoglycemia), and long-term damage to nerves, vision, and vital organs.

Although T1D typically appears during childhood or adolescence, anyone can be at risk. According to the American Diabetes Association, more than 1.25 million Americans are living with T1D, and 40,000 will be newly diagnosed each year.

Type 1 Diabetes Symptoms

Signs are often subtle, but they can become severe. They include:

• Extreme thirst
• Increased hunger (especially after eating)
• Dry mouth
• Upset stomach and vomiting
• Frequent urination
• Unexplained weight loss, even though you’re eating and feel hungry
• Fatigue
• Blurry vision
• Heavy, labored breathing (your doctor may call this Kussmaul respiration)
• Frequent infections of your skin, urinary tract, or vagina
• Crankiness or mood changes
• Bedwetting in a child who’s been dry at night

Signs of an emergency with type 1 diabetes include:

• Shaking and confusion
• Rapid breathing
• Fruity smell to your breath
• Belly pain
• Loss of consciousness (rare)

Type 1 Diabetes Causes

Insulin is a hormone that helps move sugar, or glucose, into your body’s tissues. Your cells use it as fuel.

Damage to beta cells from type 1 diabetes throws the process off. Glucose doesn’t move into your cells because insulin isn’t there to do the job. Instead, it builds up in your blood, and your cells starve. This causes high blood sugar, which can lead to:

• Dehydration. When there’s extra sugar in your blood, you pee more. That’s your body’s way of getting rid of it. A large amount of water goes out with that urine, causing your body to dry out.
• Weight loss. The glucose that goes out when you pee takes calories with it. That’s why many people with high blood sugar lose weight. Dehydration also plays a part.
• Diabetic ketoacidosis (DKA). If your body can’t get enough glucose for fuel, it breaks down fat cells instead. This creates chemicals called ketones. Your liver releases the sugar it stores to help out. But your body can’t use it without insulin, so it builds up in your blood, along with the acidic ketones. This mix of extra glucose, dehydration, and acid buildup is known as ketoacidosis and can be life-threatening if not treated right away.
• Damage to your body. Over time, high glucose levels in your blood can harm the nerves and small blood vessels in your eyes, kidneys, and heart. They can also make you more likely to get hardened arteries, or atherosclerosis, which can lead to heart attacks and strokes.