Diabetes symptoms: When diabetes symptoms are a concern

Diabetes symptoms are often subtle. Here's what to look for — and when to consult your doctor. By Mayo Clinic Staff

Early symptoms of diabetes, especially type 2 diabetes, can be subtle or seemingly harmless — if you have symptoms at all. Over time, however, you may develop diabetes complications, even if you haven't had diabetes symptoms.

In the United States alone, nearly 7 million people have undiagnosed diabetes, according to the American Diabetes Association. But you don't need to become a statistic. Understanding possible diabetes symptoms can lead to early diagnosis and treatment — and a lifetime of better health. If you're experiencing any of the following diabetes signs and symptoms, see your doctor.

Excessive thirst and increased urination

Excessive thirst and increased urination are classic diabetes symptoms.

When you have diabetes, excess sugar (glucose) builds up in your blood. Your kidneys are forced to work overtime to filter and absorb the excess sugar. If your kidneys can't keep up, the excess sugar is excreted into your urine along with fluids drawn from your tissues. This triggers more frequent urination, which may leave you dehydrated. As you drink more fluids to quench your thirst, you'll urinate even more

Fatigue

You may feel fatigued. Many factors can contribute to this. They include dehydration from increased urination and your body's inability to function properly, since it's less able to use sugar for energy needs.

Weight loss

Weight fluctuations also fall under the umbrella of possible diabetes signs and symptoms. When you lose sugar through frequent urination, you also lose calories. At the same time, diabetes may keep the sugar from your food from reaching your cells — leading to constant hunger. The combined effect is potentially rapid weight loss, especially if you have type 1 diabetes.

Blurred vision

Diabetes symptoms sometimes involve your vision. High levels of blood sugar pull fluid from your tissues, including the lenses of your eyes. This affects your ability to focus.

Left untreated, diabetes can cause new blood vessels to form in your retina — the back part of your eye — and damage established vessels. For most people, these early changes do not cause vision problems. However, if these changes progress undetected, they can lead to vision loss and blindness.

Jun. 25, 2013 See more In-depth