Type 1 Diabetes Symptoms and Warning Signs

What are the symptoms of type 1 diabetes?

Warning signs of new-onset type 1 diabetes (T1D) often appear suddenly and require immediate attention. The most common symptoms of type 1 diabetes are:

Extreme thirst (polydipsia)

Extreme thirst is caused by frequent urination as the kidneys attempt to filter sugar out of the bloodstream.

Frequent urination (polyuria)

Polyuria is frequent—and often large amounts of—urination. When your blood sugar is over 180 mg/dL, your kidneys work to filter it out of your system. This requires fluid to flush it from your system, which can lead to extreme dehydration and increased thirst.

Unexplained weight loss

Unexpected weight loss is often a sign your body can’t get adequate energy from the carbohydrates in the food you eat and is breaking down fat for energy.

Fatigue

One of the more common type 1 diabetes symptoms is fatigue. Being constantly tired may be a sign that the body is having trouble turning sugar in the bloodstream into energy.

Dry mouth and itchy skin

If your body is dehydrated, even for a short period of time, dry mouth and itchy skin can occur.

Less common type 1 diabetes symptoms

The following symptoms are not as common in new-onset T1D, but should be discussed with your doctor:

Fruity odor on the breath
Fruity-smelling breath is a sign of a buildup of ketones in the blood. It can also be a symptom of diabetic ketoacidosis (DKA), which is a medical emergency and must be treated immediately.

Vision changes
High blood sugar levels can damage the blood vessels in the eye, which sometimes causes blurred vision or other eyesight problems.

Increased appetite
Without insulin, your body can’t convert the carbs you eat into energy. Because your cells can’t get energy from food, your brain sends out hunger signals. Increased appetite is most common in children with undiagnosed T1D.

Irritability and mood swings
Blood sugar fluctuations can make you feel like you’re on an emotional rollercoaster or cause you to be short-tempered.

Slow healing cuts
Having slow-healing cuts or sores is also a potential sign of diabetes. High blood sugar levels can affect blood flow and cause nerve damage, which makes healing difficult.

Yeast infections
Yeast infections may occur in men and women who have type 1 diabetes because of yeast feeding on excess glucose in the blood.

Type 1 diabetes symptoms in children

Children with type 1 diabetes often have the following symptoms:

Increased thirst
Increased urination or bedwetting
Increased hunger
Fatigue
Weight loss
Others associated with DKA in later stages (e.g., stomach pain, vomiting)

Support for Newly Diagnosed Children

Learn more about blood sugar levels

High blood sugar (hyperglycemia)

Having too much sugar in your blood is called high blood sugar, or hyperglycemia. The target blood sugar range for most people living with type 1 diabetes (T1D) is 70 to 180 mg/dL.

High blood sugar is treated with insulin.

Learn More About High Blood Sugar

Low blood sugar (hypoglycemia)

When you have too little sugar in your blood, it is called low blood sugar, or hypoglycemia. Low blood sugar in people with type 1 diabetes (T1D) usually means anything lower than 70 mg/dL.

Low blood sugar is treated with fast-acting carbohydrates.

Learn More About Low Blood Sugar

Diabetic ketoacidosis (DKA)

Diabetic ketoacidosis, or DKA, is a medical emergency and must be treated immediately.

DKA happens when your cells can’t get fuel from the sugar in your blood and break down fat instead. This creates ketones, which are acids produced in your liver and released into your blood when your body breaks down fat for energy. When ketones build up, it leads to too much acid in the blood (acidosis).

The risk for ketones and DKA is higher during illness and when insulin doses are missed, or infusion sites are occluded. Insulin is essential to help the body clear ketones.

Signs of DKA

Ketones in the urine or blood
Extreme exhaustion or fatigue
Nausea, vomiting, or abdominal pain
Difficulty breathing
Fruity odor on the breath
Confusion or difficulty paying attention
Loss of consciousness

Be prepared to check for ketones

It is important to have a way to check for ketones, either using urine test strips or blood test strips with a ketone meter.

Have a blood or urine ketone test kit on hand.
Check expiration dates on kits and discard expired test strips.
Read the package when there isn’t an emergency to learn how to use it. Ask your diabetes educator for support.
To make sure you understand the instructions, do a sample check-in consultation with your healthcare team during a clinic visit.

Learn more about Ketones and DKA