When you have diabetes, you'll need to visit your eye doctor regularly for exams to avoid eye problems. High blood sugar (glucose) increases the risk of trouble. In fact, diabetes is the leading cause of blindness in adults ages 20 to 74.
Don't buy a new pair of glasses as soon as you notice you have blurred vision. It could just be a temporary problem caused by high blood sugar levels. The lens of the eye could swell, which changes your ability to see.
To correct it, you need to get your blood sugar back into the target range (70-130 milligrams per deciliter or mg/dL before meals, and less than 180 mg/dL 1 to 2 hours after a meal). It may take as long as 3 months after your blood sugar is well controlled for your vision to fully get back to normal.
But blurred vision could be a symptom of more serious eye problem, too.
A cataract is a clouding or fogging of the normally clear lens of the eye. The lens is what allows us to see and focus on an image, just like a camera. Although anyone can get cataracts, people with diabetes tend to get them at an earlier age, and the condition gets worse faster.
Because you have a cloudy area in the lens of your eye, you won't be able to focus light properly, so you won't see as well. Symptoms include blurred or glared vision.
Cataracts can be fixed with surgery. The cloudy lens is usually removed and replaced with a clear man-made lens.
When fluid inside the eye doesn't drain properly, pressure can build up. The increase in pressure can damage nerves and the blood vessels in the eye, causing changes in vision.
Open-angle glaucoma, the most common form, can be treated with medications. They lower the eye's pressure by speeding up drainage of aqueous humor or causing your body to make less of it.