A probiotic food contains live bacteria or yeast with various health benefits; it is beneficial for replacing or supplementing damaged gut flora. Probiotics can be taken as a nutritional supplement, but of course fermented foods are an excellent source. Probiotic means ‘for life’, in contrast to the word antibiotic which means ‘against life’.
Good bacteria, or probiotics, are only really helpful if they survive in the stomach and make it to the intestine. As the bacteria in the fermented food are used to an acidic environment already, they are very likely to survive in the stomach and make it to the small intestine. A probiotic supplement with beneficial gut bacteria does not always survive the acidic stomach environment. For this reason, traditionally fermented foods might fare better than commercial probiotic supplements, and this is indicated by some research. It’s worth noting that if you heat your fermented foods up or use them in cooking, then you will kill most of these bacteria.