Conflation is very easy to do here. If you are very sick, you probably aren't drinking coffee (it's a mild stomach irritant).
So there is a correlation between coffee and being healthy, but causation is very messy.
So there is a correlation between coffee and being healthy, but causation is very messy.
Again, I'm very very comfortable with. Wait -- millions of people have been drinking coffee daily FOR YEARS, with VERY FEW visibly super-harmful side effects.
That data is as good as, or perhaps better than, modern medical data -- which ITSELF cuts both ways.