Experience is the teacher for me. I had seasonal allergies until I started taking probiotics. Then I got interested in making kefir as an alternative to that expense, especially as I find it easier to make than yogurt. We have home grown raspberries and they go great blended in kefir. Yogurt is associated with longevity historically in various cultures, so I don't think there is much argument that it's not good for you.

I don't think we know enough about the microbiome yet to know what's going on with things like itching following fermented foods, which I've also experienced. Is it the dose, the accompanying prebiotic fiber or lack thereof in the diet, or something else?

I'm convinced that it is important, as is fiber, which can't be lumped into just one category as there's a big difference between soluble and insoluble. Adding "roughage" type fiber, without extra water especially, is a prescription for constipation. Whereas soluble fiber may aid weight loss: https://www.healthline.com/nutritio...you-lose-weight I went on Brenda Watson's high fiber diet back in the day and it worked so well, I became interested. I also lost a large amount weight eating a high whole grain diet back in the day (that wasn't especially low fat).

And considering the ancestral diets we may have evolved on, it makes sense to me that ancient cultures would have eaten anything edible and nourishing, which in terms of plants and insects would have included plenty of fiber. http://theplate.nationalgeographic....-in-paleo-diet/