Considering how popular fermented foods are, one would think that anything fermented would be good for health. But this is not so. Fermentation is not a healing technique, just a food preservation technique from the past. Let's take yogurt as an example. Yogurt is a dairy product, and all dairy products feed viruses and non-productive bacteria that are the source of so many chronic diseases. The claim that the microorganisms in yogurt are beneficial is only a hypothesis. The harm done by dairy products themselves, even if it's raw, unpasteurized yogurt, outweighs any theoretical benefits: milk proteins and lactose feed the microbes causing your symptoms.