Question 1

How much sleep do I really need?

Accepted Answer

Adults need 7–9 hours, but the optimal amount varies by age, activity level, and genetics. Athletes and very active people often need 8–9.5 hours. The key is not just duration but timing — aligning with your natural sleep cycles.

Question 2

What is a sleep cycle and why does it matter?

Accepted Answer

A sleep cycle lasts approximately 90–95 minutes and includes light sleep, deep sleep, and REM stages. Waking at the end of a cycle (rather than mid-cycle) makes you feel more refreshed. That’s why 7.5 hours can feel better than 8.

Question 3

Does chronotype affect how much sleep I need?

Accepted Answer

Your chronotype (early bird vs. night owl) affects your optimal sleep timing, not necessarily duration. Night owls forced to wake early accumulate sleep debt. Aligning your schedule with your chronotype improves sleep quality significantly.

Question 4

What happens if I consistently sleep less than 7 hours?

Accepted Answer

Chronic sleep deprivation increases risk of cardiovascular disease, weakens immunity, impairs cognitive function, and accelerates biological aging. Even 1 hour less per night compounds into measurable health effects within weeks.

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