I am not an expert on sleep medicine, and so I recognize it's bold to claim that the American Academy of Sleep Medicine is wrong. But they are. Many good scient

I am not an expert on sleep medicine, and so I recognize it's bold to claim that the American Academy of Sleep Medicine is wrong. But they are. Many good scientists still struggle with translating research data into real-world predictions. And these scientist don't have a reasonable causal model of the relationship between biological clocks, wall clocks, and social clocks. They assume that people's social clocks are not only associated with the wall clock, but determined by it.. Below I'll repeat part of a comment I made here: https://news.ycombinator.com/item?id=30695603 https://news.ycombinator.com/item?id=30695603 They are correct that there are negative health effects for people being on the western edge of time zones because their social clocks are earlier than their biological clocks. But this is because people synchronize their social clocks with people in their time zones. But if an entire timezone shifts by an hour, they will naturally adjust their social clocks accordingly. As a thought experiment, imagine shifting the time zone by 12 hours, so midnight was called noon and noon was called midnight. People would simply shift their social clocks by 12 hours to compensate. An actual example of this is Spain, which since WWII has been on the central European time zone, even though it is one of the most westernmost countries in Europe. According to this article, people in Spain should have more health problems and shorter lifespans, because their social clock is so much earlier than their body clocks. However as everyone who has ever been to Spain knows, the social clock in Spain does not have the same relationship to the wall clock as it does in other countries. In fact, relative to say the US, the social clock in Spain seems to be shifted a good two hours, for example with dinner at 9pm or 10pm. So their social clock relative to the sun is actually not so different from other European countries.