how much time should we be in rem sleep
These are called rapid eye movement (REM) sleep, and non-rapid eye movement (Non-REM) sleep. In adults, non-REM sleep occupies around 80 percent of the night, and REM sleep 20 percent. However, REM sleep does not occur in one large block. Actually, we go into REM sleep in cycles of around 90 minutes. That is, REM sleep occurs around once every 90 minutes.