Adding the numbers, since they settle part of this. For anyone reading later: the numbers in this thread are worth checking against a primary source before you act on them, including mine. Half the figures circulating in this community trace back to a secondary summary that dropped a qualifier.

One thing that is still open after Dr.GutHealth’s answer:

How would you tell the difference between that and the alternative explanation?

TirzTom said:

For anyone reading later: the numbers in this thread are worth checking against a primary source before you act on them, including mine.

I read this differently from TirzTom, on substance rather than tone. Filing an objection on the n=1 problem. Personal experience is genuine evidence about one person and very weak evidence about anybody else, and this thread keeps promoting the first into the second.

If somebody has the primary source to hand I would rather cite it than paraphrase it.

TirzTom said:

For anyone reading later: the numbers in this thread are worth checking against a primary source before you act on them, including mine.

That is correct as far as it goes, and here is where it stops going. Yes, and the corollary is less popular: if the reasoning holds, it also holds where it produces an answer we do not like.

If somebody has the primary source to hand I would rather cite it than paraphrase it.

TirzTom said:

For anyone reading later: the numbers in this thread are worth checking against a primary source before you act on them, including mine.

That reframing is the part I needed. Adding it to my notes with a link back to this thread.