Frequent urination, also known as polyuria, is a classic and significant sign of both type 1 and type 2 diabetes, which occurs because the kidneys try to flush out excess blood sugar, pulling water with it and leading to dehydration and increased thirst. Doctors say that in diabetes, because the level of sugar in the blood is abnormally high, not all of the sugar can be reabsorbed. Some of the excess glucose from the blood ends up in the urine, where it draws more water, resulting in large volumes of urine.
