alt Hacker NewsOr for one of my favorites, 'a glass of wine a day is healthy' because of antioxidants... or something. Except it isn't, at all. But rather as people's health deteriorates to a sufficient degree they tend to stop drinking (even if not consciously because of their own health), and so when you study light drinkers versus non-drinkers, there was enough of an undetected bias in there to make it seem that drinkers were, on average, healthier. It's easy to see echoes of that possibility in near to any study, especially observational.
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Oh this is such a nice comment. It's like saying People who live on the 5th floor are healthier than those on the ground.
Of course, the root cause being people who are unfit, sick or elderly cannot literally make it up a flight of stairs.
but if people aren't paying attention, like the vast majority of population dont, you'll suddenly have an explosion of condos that start from the 5th floor with the first 4 floors turned into something else.
and all of them have lifts!
> Or for one of my favorites, 'a glass of wine a day is healthy'
There are a few reasons why this is false, my favorite one is, they didn't control for alcoholics who stopped drinking and thus reported as non-drinkers. So the group of completely sober ones had people with liver damage etc. while those with only moderate drinkers had barely any heavy-drinkers in it.
> 'a glass of wine a day is healthy' because of antioxidants... or something. Except it isn't, at all
Also, in America, the kind of people who have a glass of wine a day (but not more) strongly correlate with those who can afford healthcare.
Similar for mediterranean diets. Turns out it’s the universal healthcare available in all the mediterranean countries both on the european and the african sides.