Sleep Health
Slow-wave sleep restores the body, strengthens the immune system and locks in long-term memories.
Growth hormone peaks during deep sleep, driving muscle repair and tissue growth.
Deep sleep boosts T-cell activity and the antibody response to vaccines.
Hippocampal replay during slow-wave sleep transfers short-term to long-term memory.
The glymphatic system clears beta-amyloid plaques most actively during deep sleep.
Cool room, no alcohol after dinner, consistent bedtime, and avoid late naps.
Last reviewed February 2026 against current US sleep medicine guidelines by the Sleep Disorder Symptoms editorial team. This article is educational and is not medical advice — see our medical disclaimer and editorial policy.
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