Melatonin is a natural hormone that is produced by the body at night. It is controlled by the amount of light that is allowed into the eye. It helps the body wind down and get ready for bed. Sometimes, when the body does not produce enough melatonin, there are exogenous options, or melatonin pills, that can help those who are having trouble falling asleep. However, those supplements come with some potential problems, of which you need to be aware. Continue reading to find out some things about melatonin that should give you pause before depending heavily on that supplement for good sleep.