Blurred vision is a potential complication experienced by diabetics. Short-term blurriness among diabetics is caused by fluid shifting into and out of the eye due to high blood sugar levels, which causes the lens of the eye to swell. As the lens changes shape, its light-focusing ability is altered, resulting in blurriness. Fortunately, this short-term blurriness resolves soon after sugar levels are lowered. Diabetes can also cause short-term blurriness when abnormally low sugar levels (hypoglycemia) exert an effect on the brain. Vision affected in this manner normalizes after glucose levels return to normal. Diabetes is just one condition that can lead to blurred vision. Blurry vision should be checked by the ophthalmologist, especially if it is sudden.