I have had severe myopia since 8 years old. Had LASIK in 1990. Ever since my vision has been variable - sometimes sharp and sometimes not. My docs said it was caused by variable hydration. It is true that a big glass of water would sometimes help my vision but it did not eliminate the problem. Since I have been controlling my BG spikes by restricting carbs, my vision has improved dramatically. I have found that I can not eat more than 10-15 grams of carbs without having my 1 hour postprandial BG go above 140. Reflecting back on my pre-PB diet, I'm guessing my 1 hour postprandial BG's must have typically been well over 200 and, considering my high carb snacking pattern, my BG probably stayed around 200 for most of the day.