[6177c40f]

Very unfortunate situation, but I'm doubtful that it's the bacteria causing it. As far as I can tell, it just doesn't produce enough formate. The body is pretty good at metabolizing formate, so it really only causes blindness from large, acute exposures, not smaller chronic exposure, AFAIK. Combine that with no other reports of blindness from other users of the Lumina probiotic, nor any similar issues appearing in rodent studies, and the bar for evidence is pretty high.

[palmotea]

> nor any similar issues appearing in rodent studies

That's addressed in the OP:

> And in case you were wondering, this wouldn’t have shown up in the original BCS3-L1 rodent toxicity studies either as most non-primate animals metabolize formate much more efficiently, including rats. This has led to difficulties creating a rodent model of methanol toxicity, in fact.

[6177c40f]

I'm not certain they're correct there, as various studies seem to quote different numbers. Either way, I'm not sure rats are so much more efficient that it would matter: e.g. if the half-life in rats was a few tens of minutes vs the hour or so half-life in humans, would that make the difference between no toxicity and toxicity? Still, I haven't seen other people report vision loss, so maybe the point is moot anyway.

Although, it doesn't preclude some kind of uncommon impairment to formate metabolism, which would explain why it doesn't happen to other people.