Next Diabetes can affect sight If you have diabetes mellitus, your body does not use and store sugar properly.
Diabetes can cause high blood-sugar levels, excessive thirst and urination.
It can also cause changes in the body's blood vessels, the veins and arteries that carry blood throughout your body. Because diabetes affects your body in these ways, it can affect vision by causing cataracts, glaucoma and, most importantly, damage to blood vessels inside the eye. Diabetic retinopathy is a complication of diabetes that is caused by changes in the blood vessels of the eye. The retina is a nerve layer at the back of the eye that senses light and helps to send images to your brain. When blood vessels in the retina are damaged, they may leak fluid or blood, and grow fragile, brush-like branches and scar tissue.