What is melatonin? Changes in daily habits, changes in seasons, and screen time before bed can disrupt melatonin production and throw us out of this cycle. Melatonin supplements can help. Melatonin supplements may help improve sleep quality in adults whose melatonin levels naturally decline with age. Jet lag occurs when your body's internal clock becomes out of sync with the new time zone. Melatonin can counteract jet lag, a temporary sleep disorder. It lowers dopamine levels and helps your body prepare for deep sleep. Melatonin supplements may help counteract the effects of low melatonin levels and normalize your body clock. It lets your body know it's nighttime so you can relax and fall asleep more easily. It helps calm your body before bed.