Most adults need at least seven hours regularly, but need and opportunity vary; daytime function is part of the assessment.

Sleep & Circadian - Schedules & timing

How much sleep do adults need?

Last reviewed 3 August 2026. How we write this.

Most adults need at least seven hours regularly, but need and opportunity vary; daytime function is part of the assessment.

One short night is different from chronic restriction. Regularly insufficient sleep affects alertness, mood, metabolic health and accident risk.

Quality cannot replace quantity

A tracker score or deep-sleep percentage cannot make a five-hour sleep opportunity adequate.

Educational content only. This does not diagnose, treat or replace individual advice from an appropriately qualified clinician.

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Sources for this classroom

Educational content only. Not medical advice, diagnosis or treatment. Always consult a qualified healthcare professional before changing your health regimen.