Well, yes, in my opinion, it is possible to have cataracts when you suffer dehydration. Generally speaking, when the loss of body fluids, mostly water, exceeds the amount that is taken in, it can lead to the water go out of the body and there is no enough water for the organs to work. In that way, dehydration can occur. And it will just affect our eyes and lead to some eye diseases, such as bloodshot eyes, red eyes, even dark circles and eye bags under your eyes. On the other hand, cataracts can be caused by dehydration too. So just be careful about it.