yeah. that’s been my experience as well. my doctor gave me the impression that melatonin helps set the cycle but magnesium glycinate is what calms the body.
This.
And maybe anecdotal, but my experience of people who have used melatonin is that they sleep very deeply, but for a shorter amount of time. But likely they will wake up after around 6/7 hours sleep, rather than the recommended 8 hours of sleep. And once woken up, it's very hard to go back to sleep.
7 is enough for a lot of adults. especially 7 hours of quality sleep. After seeing a sleep doctor I realized that stressing out about not getting exactly 8 hours each night was part of my problem! I did a lot of experimentation to find my optimal hours and it was not quite 8. Trying to force extra hours doesn't really work.
AFAIK 7-9 hours is the commonly used range, anything less than 7 hours or anything more than 9 can have detrimental effects on how well rested you feel after waking up. Where did you get the notion that adults need exactly 8 hours on the dot?