Most adults need about 1.5 to 2 hours of deep sleep per night. This is roughly 13% to 25% of the total recommended 7 to 9 hours of sleep per night for adults. Deep sleep is essential for physical restoration, muscle repair, immune system strengthening, and overall health. The amount of deep sleep tends to decrease with age, and factors like exercise and health can also influence how much deep sleep one requires. Feeling rested and alert during the day is a good indicator of getting sufficient deep sleep. In summary:
- Recommended deep sleep for adults: 1.5 to 2 hours (90 to 120 minutes) per night
- Deep sleep as a percentage of total sleep: around 13% to 25%
- Total sleep recommended for adults: 7 to 9 hours
- Deep sleep decreases with age but is crucial for health and recovery.
These findings come from recent health and sleep research sources.