The majority of your diet will facilitate the production of beneficial microorganisms.
If you eat a bunch of wheat and sugar, you'll end up with a major Candida overgrowth. This will cause further sugar and bread cravings. Next will be serious inflammation in various organs.
Eat veggies and inoculate with old fashioned vegetables pickled the old fashioned way, before we depended on refrigeration, then eat some with meals from time to time. You will get a boost in energy, B vitamin production, and all kinds of benefits too numerous to describe here.
Is there anything pickled the old fashioned way that you can buy in the grocery store?
I don't know of any except for the Korean Kimchi.
I've seen it in the refrigerator of the health food section at a couple of big supermarkets. The cold prevents it from "working". Even then, when you get it home, cover it with a dish towel as you unscrew the lid because it will release the gas and make a small mess.
This can be the quick starter for your own vegetables.
There are other ways that work well too.
I've used whey from yogart, kefirs, and also the atmosphere in your house can often work, ( funny enough.) The key is procedure, like adding enough salt and covering it completely with that brine. Watch the youtube videos to get ideas.
The finished product shouldn't smell like compost.
It will acidify and get progressively vinegary from the lactic acid.