J. Todd Arnedt, assistant professor of psychiatry and neurology at the University of Michigan, said: "It's clear that a substantial portion of the population uses alcohol on a regular basis to help with sleep problems. This perception may relate to the fact that alcohol helps people fall asleep quickly and they may be less aware of the disruptive effects of alcohol on sleep later in the night." Until now, Arnedt said, very few alcohol-administration studies have included women, and since females metabolize alcohol differently than men, there could be gender differences in its effects on sleep.