[astrange]

Each probiotic is different and each person is different, so it's hard to make the recommendation actionable.

You'd have to know what's already in your intestines, and the best we have are poop tests, one of which (uBiome, YC S14) famously failed and is being prosecuted as insurance fraud, so doctors probably don't want to get into that. (There are still going ones like Viome that might give you interesting results.)

Fermented foods aren't all the same too; yogurt is milder than kimchi for sure.