Diabetes

Diabetes mellitus refers to a group of diseases that affect how your body uses blood sugar (glucose). Glucose is vital to your health because it's an important source of energy for the cells that make up your muscles and tissues. It's also your brain's main source of fuel.

If you have diabetes, no matter what type, it means you have too much glucose in your blood, although the causes may differ. Too much glucose can lead to serious health problems.

Chronic diabetes conditions include type 1 diabetes and type 2 diabetes. Potentially reversible diabetes conditions include prediabetes — when your blood sugar levels are higher than normal, but not high enough to be classified as diabetes — and gestational diabetes, which occurs during pregnancy but may resolve after the baby is delivered.


Symptoms Causes Risk factors Complications Prevention

Diabetes symptoms vary depending on how much your blood sugar is elevated. Some people, especially those with prediabetes or type 2 diabetes, may not experience symptoms initially. In type 1 diabetes, symptoms tend to come on quickly and be more severe.

Some of the signs and symptoms of type 1 and type 2 diabetes are:

  • Increased thirst
  • Frequent urination
  • Extreme hunger
  • Unexplained weight loss
  • Presence of ketones in the urine (ketones are a byproduct of the breakdown of muscle and fat that happens when there's not enough available insulin)
  • Fatigue
  • Irritability
  • Blurred vision
  • Slow-healing sores
  • Frequent infections, such as gums or skin infections and vaginal infections

Although type 1 diabetes can develop at any age, it typically appears during childhood or adolescence. Type 2 diabetes, the more common type, can develop at any age, though it's more common in people older than 40.

When to see a doctor

  • If you suspect you or your child may have diabetes. If you notice any possible diabetes symptoms, contact your doctor. The earlier the condition is diagnosed, the sooner treatment can begin.
  • If you've already been diagnosed with diabetes. After you receive your diagnosis, you'll need close medical follow-up until your blood sugar levels stabilize.
© 1998-2015 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. Terms of use