Chapter 9: Sleep and the Dark You Have Lost
For 300,000 years, every cell in your body was synchronized to the sun. Artificial light shattered that synchrony just 145 years ago -- and the consequences are devastating.
◆ Key Insights
A single night of disrupted sleep alters the expression of over 200 million cellular processes tied to your circadian clock
Shift workers have a 6% higher cancer risk -- the WHO classifies circadian disruption as a probable carcinogen
Your ancestors experienced 12+ hours of darkness per night; the average modern human gets 3.5 hours between last screen and waking
The glymphatic system flushes metabolic waste from the brain during deep sleep -- chronic short sleep leaves neurotoxins accumulating
Nobel Prize-winning research confirms: circadian rhythms govern not just sleep, but digestion, immunity, mood, and DNA repair
Read the full chapter to learn what 145 years of artificial light have done to the 300,000-year-old clock inside every cell.
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