The older I get, the more I think that medical "researchers" don't have any clue and really don't do more than measure correlation.
Caffeine is bad for you, but then Coffee is good for you.
Bacon is bad for you, but then Bacon is good for you.
Wine is bad for you, but the wine is good for you.
Cigarettes are good for you, but then cigarettes are bad for you.
Heroin is good for you, then heroin is bad for you.
Cannabis is good for you, then it's bad for you, then it's good for you if you're sick.
And so on and so forth. Anymore, unless some researcher can show me a video of a test subject drinking a beer and then spontaneously combusting, I'll just carry on.