I've been taking melatonin for the last 3 months since cutting out alcohol and it seemed to help with falling into a sleep. As Friday I stopped taking it because I don't want to be reliant on something for sleep other than exercise and proper diet. Anecdotally, my sleep the last three nights since cutting it out have been horribly restless and not fulfilling. I'd rather not take it but if after a week normal sleep doesn't return I might since it sounds like it's relatively benign compared to other sleep aids.

Are there any longitudinal studies about years of usage?