how many hours of deep sleep is needed

Most adults need around 1.5 to 2 hours of deep sleep per night. This amount typically represents about 20-25% of the total recommended sleep time of 7 to 8 hours per night. Deep sleep is the stage where the body undergoes important functions like muscle relaxation, tissue repair, hormone release, and immune system strengthening. Not getting enough deep sleep can affect physical and mental health as well as daytime alertness. Therefore, aiming for about 1.5 to 2 hours of deep sleep is crucial for feeling rested and maintaining overall health.