“Melatonin is a hormone that is naturally made by your brain in response to darkness,” says sleep specialist Marri Horvat, MD. “When someone takes melatonin, they are either trying to increase the amount of this hormone overall or increase the amount they have in their body at a certain time to help them fall asleep.”

While there are some possible setbacks to taking melatonin (depending on how your body reacts), it isn’t addictive. Turns out, even if you depend on melatonin to make you fall asleep, it won’t cause your body to become dependent on it.
“As we age, we have a natural decrease in the amount of melatonin we produce, so supplementation can often be helpful,” Dr. Horvat explains.
Read more at Cleveland Clinic