how many hours of rem sleep do you need

For most healthy adults, about 20-25% of total sleep time should be spent in REM sleep. This typically translates to around 1.5 to 2 hours of REM sleep per night if you get the recommended 7-9 hours of total sleep. REM sleep usually occurs in multiple cycles throughout the night, each lasting longer as sleep progresses, with the final REM cycle sometimes lasting up to an hour. The amount of REM sleep tends to decline with age. Getting sufficient REM sleep is important for processes like memory consolidation, emotional regulation, learning, and brain function.