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What is sleep and why do we need it?

Medicine & HealthLesson on requestFree to read

Quick answer

Sleep is a daily state of rest where your brain and body recover. Far from 'switching off,' your brain stays busy — clearing waste, storing memories, and repairing tissue. Skip it, and focus, mood, and health all suffer. A daily state where brain and body recover.

Key things to understand

  1. A daily state where brain and body recover.
  2. The brain cycles through light, deep, and REM stages.
  3. It consolidates memories and clears waste.
  4. Most adults need about 7–9 hours.

People also ask

Why do we need sleep?
Sleep lets the brain store memories and clear waste, and the body repair tissue and balance hormones — it's essential, not optional.
How much sleep do I need?
Most adults need 7–9 hours; teenagers and children need more.
What happens if I don't sleep enough?
Even short-term, it harms focus, memory, and mood; long-term, it raises the risk of heart disease, diabetes, and weak immunity.