This is an interesting article. Apparently Lactobacillus reuteri creates B12 in your gut. And other things too, like balancing the microbiome and fixing dysbiosis.
I just ordered my Dr Matthew #1 Probiotic that has Lactobacillus reuteri.
What is interesting, and I will need to study this, is that the paper says the various benefits are strain specific (and it lists various strains). So my new probiotic may just turn out to be a starter kit while I now have to identify the specific strains I need and track them down
Role of Lactobacillus reuteri in Human Health and Diseases frontiersin.org/articles/10...