Sort of interesting data. Although the discussion in the article around it is weak. Apparently the answer to "who exactly is getting that hypothetically ideal eight hours of sleep that is always recommended?" is "no one" or not many. Also interesting is the data for Japan, given that Japan is a country that is one of the very top longevity countries for longevity. I am pretty sure that there are lots of big pharma companies getting rich selling Americans sleeping medication because the patients complain of getting only the amount of sleep that the Japanese seem to get, based on this limited data anyway. https://medicalxpress.com/news/2025-05-healthy-amount-differs-country.html