5. Blindness
Prolonged high levels of sugar in the blood damages the blood vessels that supply nutrients and oxygen to the retina, the sensitive part of the eye responsible for receiving light from the lens and converting that into electrical signals that the brain can translate into an image. Not only that, the tiny nerves found in the retina, as well as the optic nerve are also sensitive to high sugar levels and can be affected just the same. Damage to the retina caused by diabetes is known as diabetic retinopathy, a condition that could eventually lead to blindness.
