Diabetics (particularly those in whom the blood sugar levels are not really well controlled) can develop earlier cataracts than is normal. Cataracts happen when the lens of the eye gets cloudy. Diabetics can get a particularly aggressive type of cataract that comes on rather quickly called a Posterior Subcapsular Cataract. With that type of cataract, it’s almost like looking through ground glass. So they’ll get a lot of glare like a dirty windshield or something – a ton of glare. They’ll also start having problems with their reading vision.