Why Do You Wake Up at 3am?

Why do you wake up at 3am? Waking up in the middle of the night might not be a sleep problem at all. For much of history, it was normal. We visit a Hadza camp in Tanzania where someone is almost always awake, villagers in 1600s England who got up between a "first sleep" and a "second sleep", and a sleep lab where modern volunteers fell into the same pattern. Then why 3 a.m. feels so bad, and what changed. Chapters: 0:00 Intro 1:10 Take a guess 2:42 Two sleeps 4:17 The lab test 6:02 The catch 7:18 Why 3 a.m. 8:45 Recap 9:12 What changed 10:40 Final thoughts Sources (every claim in this video was fact-checked): Wikipedia: Hadza people: https://en.wikipedia.org/wiki/Hadza_p... Duke Today 2017: https://today.duke.edu/2017/07/live-g... CARTA abstract: https://carta.anthropogeny.org/node/3... UNLV: https://www.unlv.edu/news/article/sle... timeanddate: London, December: https://www.timeanddate.com/sun/uk/lo... BBC: The myth of the eight-hour sleep: https://people.uncw.edu/imperialm/unc... Medievalists.net: https://www.medievalists.net/2023/11/... Incidental Economist: https://theincidentaleconomist.com/wo... Pocket/BBC: the forgotten medieval habit of two sleeps: https://getpocket.com/explore/item/th... PubMed 10607034: https://pubmed.ncbi.nlm.nih.gov/10607... Wikipedia: Thomas Wehr: https://en.wikipedia.org/wiki/Thomas_... Psychiatric Times: Broken sleep may be natural sleep: https://www.psychiatrictimes.com/view... North Coast Journal: https://www.northcoastjournal.com/lif... PMC4763365 (Ekirch, Sleep 2016): https://pmc.ncbi.nlm.nih.gov/articles... Segmented sleep in a nonelectric, small-scale agricultural society in Madagascar: https://metatoc.com/papers/99365-segm... PMC6899797: https://pmc.ncbi.nlm.nih.gov/articles... PMC4720388: https://pmc.ncbi.nlm.nih.gov/articles... National Geographic: https://www.nationalgeographic.com/sc... UCLA Health: https://www.uclahealth.org/news/relea... UCLA sleep lab: https://teams.semel.ucla.edu/sleep-re... Sleep Foundation: stages of sleep: https://www.sleepfoundation.org/how-s... CTV News: https://www.ctvnews.ca/lifestyle/why-... Natural Medicine Journal: role of cortisol in sleep: https://naturalmedicinejournal.com/jo... ScienceAlert: https://www.sciencealert.com/your-3am... Wikipedia: Human body temperature: https://en.wikipedia.org/wiki/Human_b... Frontiers: https://frontiersin.org/journals/netw... PMC9083440: https://pmc.ncbi.nlm.nih.gov/articles... Penn CBT-I stimulus control handout: https://www.med.upenn.edu/cbti/assets... Psychology Today: CBT-I stimulus control: https://www.psychologytoday.com/gb/bl... New videos regularly. If you enjoyed this, subscribe to Never Knew Till Now and tell us in the comments what surprised you most. #sleep #history #insomnia