Night owl sleeps

Only three months ago (8 April, "Night owl") I wrote how I have always managed with 6 hours of sleep every night through my life. Occasionally to make up for the accumulated sleep debt, I would have a night of 8 or 9 hours of sleep. Otherwise if I slept more than 6 hours, I often felt lethargic the next day. But in these three months I started to notice that I get drowsy during the day and sometimes needed a nap in the afternoon. I started to think that perhaps I needed more sleep. At 77, I realized, I am no longer 70, though logically with slower metabolism in advancing age, I should need less sleep than when I was younger. Then, a few days ago I read an article in the July-August Harvard Magazine that, for those workaholics who sleep six or fewer hours a day -- some 16% of the population -- ten hours of sleep at once recharge us but only for a short term and sleep deficit is never recovered. More alarmingly, the Guardian reported recently (5 May, from the journal Sleep) that people who sleep less than six hours a night are 12% more likely to experience a premature death over the period of 25 years (unless one belongs to the population's 3% with a certain inherited genetic mutation). Statistics states generalities which may or may not apply to individual cases. Still, this is a troublesome news to someone like myself who aspires to live to 100. So, I now started to rise later since it it difficult for a hardcore night owl to retire before midnight. After the first night of 8-hour sleep, I found myself alert all afternoon the next day; but after a few nights of almost 8-hours of sleep, I was getting sleepy again right after breakfast. So, we'll see.