Overview
- Most adults should aim for 7–9 hours of sleep per night, with older adults generally advised to get 7–8 hours to support recovery.
- Adults aged 18–25 typically produce more melatonin, fall asleep faster, and prefer later bedtimes with later wake times.
- From 26–44, the sleep–wake rhythm is usually stable as melatonin gradually declines, a change that can contribute to sleep problems.
- Between 45–59, hormone-driven disruptions, especially during menopause, are common and many people may need slightly more sleep to feel fully restored.
- From 60 onward, sleep timing tends to shift earlier and disorders like insomnia and sleep apnea become more common, making daylight exposure, regular schedules and relaxing evening routines helpful for cognition and immunity.