I think there are significantly more people who eat too many carbs than people who drink too much water.

Speaking for just myself, I used to feel that sugar low after my lunch, and I know that craving for more carbs. I gained too much weight as a result. Now I've cut down on my carbs and I mostly snack on veggies these days and try not to overdo carbs at lunch, and that seems to help at least with that sugar low.