Quote Originally Posted by CFTraveler
You may want to be careful with melatonin- it's extracted from animal brains (beware of the prions) so it's the only supplement that I would advise to make sure it's synthetic. Another thing about it is that if you start using it routinely your body will stop making it's own, so you want to only use it when you absolutely have to, like to reset your circadian clock, for example.
good tip!