Higher doses and longer durations of melatonin use decrease sleep latency and increase total sleep time.

“trials with longer duration and using higher doses of melatonin demonstrated greater effects on decreasing sleep latency and increasing total sleep time”

“a meta-analysis of 19 randomized control trials demonstrates that melatonin decreases sleep onset latency increases total sleep time and improves overall sleep quality”

“So as a result, melatonin in experimental and clinical studies has been shown to improve sleep latency. So that means it can help people to fall asleep. But it might not be that good in sustaining sleep throughout the night.”