Diabetes symptoms occur when glucose (blood sugar) levels in the body become abnormally elevated. The most common symptoms of diabetes include thirst, fatigue, frequent or increased urination, and blurry vision, but symptoms do vary from one person to the next and depend on which type of diabetes you have. Symptoms of type 1 diabetes tend to begin abruptly and dramatically. In type 2 diabetes, the symptoms are similar but develop slowly, or there may be no symptoms at all. It is common for no symptoms to be present in gestational diabetes. In some cases, your symptoms may seem vague or harmless. It is essential that if you experience one or more of these symptoms on a regular basis, you see your doctor immediately for a diabetes screening and blood tests.

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Common Diabetes Symptoms


Diabetes causes your blood glucose levels to rise. Increased glucose levels cause your body to pull fluid from your cells into the bloodstream and deliver the increased load to your kidneys, causing them to produce more urine than normal. Frequent urination, another common symptom, causes you to feel thirsty and thus drink more liquids, compounding the problem.

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Weight loss

Your body's inability to properly use the glucose generated from the foods you eat, as well as the significant number of calories lost to increased urination, cause your body to break down other energy sources available—such as fat—which can result in weight loss. You may be eating normally and constantly feel hungry yet continue to lose weight.

Learn other causes of weight loss.


Glucose is a primary source of fuel for the body. If you have diabetes, your body's inability to convert glucose into energy will inevitably lead to fatigue, ranging from a general worn-down feeling to exhaustion.  

Learn other causes of fatigue.

Blurred Vision

Abnormally high glucose levels in the blood can also lead to eye problems such as swelling of the lens, which causes blurred vision. Adequately controlling your blood sugar levels can help correct this symptom over time. Left undetected, though, diabetes can lead to more serious eye problems such as cataracts, glaucoma, and retinopathy. In fact, diabetes is the leading cause of blindness in adults age 20 to 74.

Learn other causes of blurred vision.

Recurring Infections

High glucose levels in your body's tissues may hinder the body's ability to heal and make you more susceptible to various kinds of bacteria and infections, especially of the skin, kidneys, bladder, and feet.

Advanced Diabetes Symptoms

Although some people with diabetes may have no symptoms or mild symptoms that seem relatively harmless, untreated diabetes can result in dangerously high levels of blood sugar, called ketoacidosis. (Ketoacidosis is rare in type 2 diabetes because insulin is still being produced.) This condition can cause:

Dangerously low levels of blood sugar, called hypoglycemia, are sometimes associated with diabetes treatments. Hypoglycemia can cause: