One 'Shop Stop: Cutler Haters Gonna Hate (Animated)
Cutler's 'Night Blindness'
Diabetic retinopathy (the most common visual issue in diabetics), which can cause night vision issues, takes years of consistently high blood sugar to start to cause problem. It come from slowly developing vascular changes in the retina in response to chronically elevated sugar levels. There are sometimes acute visual problems if your blood sugar spikes and causes increased pressure in the eye (glaucoma), but that causes blurry vision and is reversible.
Cuter has type I diabetes (autoimmune destruction of of his insulin-producing cells), not type II (insulin resistance from too much fat tissue), even though it was first diagnosed as an adult. He also has amazing care and control of his sugar levels (he can afford the best medical care available). It has been reported that he gets his blood sugar checked during that game itself, sometimes as often as after every series, with correcting action taken if necessary (drink some juice if low, take a shot of insulin if high). His sugar levels may even be more regulated than us non-diabetics due to the frequency of monitoring he goes through.
As long as Cutler and his team doctors are vigilant (and there’s no reason to believe they aren’t), diabetes will never be a problem for him during his playing career. It was before it was diagnosed, and it may 20 years after he retires (if he’s not careful about controlling his sugar), but not now.