7.4 Sleep Changes Across the Lifecycle

Our sleep needs change throughout life. Newborns and toddlers generally require anywhere from 11 to 17 hours of sleep per 24 hours, school-aged children usually need about 10, and adolescents tend to function best with about nine. The recommendation for adults is seven to nine hours of sleep per night. The National Sleep Foundation created these recommendations after a panel of experts systematically reviewed over 300 current scientific publications about the topic (Hirshkowitz et al., 2015). Further, as people age, they tend to need less sleep up until about age 60 when sleep needs plateau (Hirshkowitz et al., 2015;  Ohayon et al., 2004). The makeup of sleep also changes over time; the proportion of time spent in REM decreases from over 50% of total sleep time at birth to 20% to 25% at adolescence. Proportion of REM sleep to NREM sleep remains stable for several decades and tends to decline again after age 65 years (Hirshkowitz, 2004).

The National Sleep Foundation provides population-level recommendations for the number of hours of sleep necessary per day. However, individuals will have different sleep needs. For example, seven hours may be enough for one person to feel rested, whereas another may need nine to be at their best.