The_Contagion_Myth_Why_Viruses_(Including_Coronavirus)_Are_Not_the_Cause_of_Disease_by_Thomas_S._Cowan,_Sally_Fallon_Morell

Fermented condiments like raw pickles and sauerkraut, fermented sauces
like ketchup, and fermented beverages like kefir and kombucha are critical
components in a diet that truly nourishes and protects. Unfortunately, the
modern diet replaces raw fermented condiments with canned versions,
makes heat-treated ketchup loaded with additives, and promotes truly toxic
and heavily sweetened soft drinks instead of artisanal fermented beverages.
The public first learned about the benefits of lactic acid–producing
bacteria in fermented foods, especially fermented milk products like yogurt,
from bacteriologist and Nobel Prize winner Ilya Mechnikov, a
contemporary of Louis Pasteur. Mechnikov is credited with the discovery of
macrophages, which turned out to be the major defense mechanism in our
innate immune system. He proposed the theory that white blood cells could
engulf and destroy toxins and bacteria, which met with skepticism from
Pasteur and others. At the time, most bacteriologists—always assuming that
natural processes are detrimental—believed that white blood cells ingested
pathogens and then spread them further through the body.
Unlike Pasteur, who believed that all bacteria were bad, Mechnikov
credited the good health and longevity of Bulgarian peasants to their daily
consumption of (fermented) yogurt and the lactic acid–producing bacteria it
contained.
Mechnikov, a colorful and passionate figure, twice attempted suicide—
the first time by an opium overdose and the second time by injecting
himself with the spirochete of relapsing fever (akin to malaria). 18 He
concluded that it was his habit of eating Bulgarian yogurt that protected him
against the spirochete toxins and allowed him to survive. He also
experimented on himself and others by drinking cholera bacteria during the
1892 cholera epidemic in France. He and one volunteer did not get sick, but
another volunteer almost died. He then discovered that some microbes
hindered the cholera growth, whereas others stimulated the production of
cholera toxins. He concluded that the proper cultivation of intestinal flora