Above 85%
Sleep efficiency is a critical metric for assessing sleep quality, reflecting how well an individual transitions from lying in bed to achieving restorative sleep. High sleep efficiency is associated with uninterrupted sleep cycles that facilitate physical recovery, memory consolidation, and emotional regulation. Poor sleep efficiency, marked by frequent awakenings or difficulty falling asleep, can disrupt these processes, leading to fatigue, impaired cognitive function, and increased risk of neurodegenerative diseases like Alzheimer's. By evaluating sleep efficiency, individuals can identify underlying issues such as insomnia or sleep apnea, which can profoundly impact neurological health and overall well-being.
Sleep efficiency is calculated by dividing the total time spent asleep by the total time spent in bed and multiplying by 100 to express it as a percentage.
For example, if someone spends 8 hours in bed but sleeps only 6 hours, their sleep efficiency would be (6/8) × 100 = 75%.
Sleep tracking devices or apps, such as fitness trackers or smartwatches, often automate this calculation. For optimal neurological health, a sleep efficiency of 85% or higher is recommended, indicating a minimal amount of time spent awake in bed. Improving sleep efficiency may involve establishing consistent bedtime routines, minimizing disruptions like noise or light, and addressing sleep disorders when necessary.