People who reported they slept 6.5 to 7.4 hours had a lower mortality rate than those with shorter or longer sleep. The study, published in the Archives of General Psychiatry in 2002, controlled for 32 health factors, including medications.
Of course controlling for confounders does not magically mean their study is perfect - there are always confounders that are either unknown or unable to be measured, particularly in retrospective/observational studies like this. But it's not nothing.
I would have been much more impressed by using sleep as a time-varying exposure, rather than a time-fixed exposure, but the study is a rather old one.
Lumping all reports from 9.5 to 16.5 hours makes me a little nervous however - that's a range from "sleeps more than average" to "sleeps the vast majority of the day, and enough that a full time job is impossible". I'd assert those are very different people.
It may be a cue, but cues themselves are not actionable. They simply mean that more research is needed until causation is found.
The dishonesty itself is astounding and I wish people had more pride in themselves than that.
It should really be titled "For some people, seven hours of sleep might be better than eight", but that's probably not eye-catching enough.
The article supports what you are saying here:
> Other experts caution against studies showing ill effects from too much sleep. Illness may cause someone to sleep or spend more time in bed, these experts say.
There's this gem of wisdom only towards the end of the article:
> "I don't think you can overdose on healthy sleep. When you get enough sleep your body will wake you up," said Safwan Badr, chief of the division of pulmonary, critical care and sleep medicine at Wayne State University School of Medicine in Detroit.
Sleeping until you naturally wake up is generally a good strategy.
That sounds nice but doesn't fit my experience at all. If I'm in a dark room I can sleep 10-12-14 hours easily.
When my body wakes me up is not at all connected to how much sleep I need. Or certainly not directly connected.
WHAT? No no this is outrageous. This doesn't sound right. It needs to be a nice round number like 8. Yeah 8 sounds good.
Also, it's not the most outrageous hypothesis that oversleeping directly causes health problems, too. The body is complicated and poorly understood.
Peak performance exercise can demand 9+ hours of sleep. I'd be reluctant to categorize sleep needs based on exercise regime.
You literally just did that.
Citation needed.
I don't understand how people can honestly report stuff like this. If you are sick, you often sleep more because you are drained and tired. That's plenty to make the data look like that. Sleeping more doesn't necessarily make you sick in the first place. There's no point bringing this up because it would be silly to try to sleep less to improve your health.