Sunday, October 16, 2016

Long Live the Microbes

The twentieth century may well go down as the century of war against microbes, mainly the bacteria (and some viruses) that were found to be responsible for infectious diseases like malaria, cholera, tuberculosis, smallpox, and the common cold and flu. Most of these diseases are communicable, so much of human hygiene became the struggle to keep ourselves clean and free of “germs,” up to and including the overuse of antibiotic soaps that were the rage a few years ago. Chlorine bleach became as common in western kitchens as salt. More recently, however, we are being told that all this cleanliness that we thought next to godliness may not be so great for us after all. Rodney Dietert’s new book, The Human Superorganism (Dutton: 2016), takes this idea to the next level. Dietert, a professor of immunogenetics at Cornell, goes so far as to state that “human mammals are not really viable. As mammals devoid of microbial partners, we lack what we need to exist” (p. 28). In this view, all that cleaning with disinfectant and the overuse of antibiotics in both children and farm animals (chickens were given antibiotics in their feed because the normal chicken immune response against pathogens caused muscle loss—and muscle loss meant small chicken breasts, while producers, and consumers, wanted large breasts, i.e. lots of white meat) has led to an epidemic of non-communicable diseases (NCDs); the latter being the result of our war on what is literally an indispensable part of ourselves—the microbiome. That is, we are composed in large part of bacteria, something that the biologist Lynn Margulis pointed out years ago. Some estimates of bacterial cells in the human body range as high as 90 percent of the total cells. This astonishing number refers to the more than 10,000 different microbial species in and on our bodies from our gut to our mouths to our skin: “one square inch of our skin can contain up to six billion microorganisms!” (5). This, in short, is what Dietert means by calling humans a “superorganism”: we humans are made up of thousands of species (mostly bacterial), including the genetic information we carry, which is not, as we have been instructed most recently, just the 22,000 genes in our mammalian genome. No, Dietert points out, “ninety-nine percent of the genetic information within the space we call you is not from your genome” but from all those microbes in your microbiome. Ten million of them.
            Does this matter? It matters crucially, according to Professor Dietert. And the reason is that with deficiencies in our microbiome, countless processes that we need for digestion, for our immune systems, for our very preferences for food and our partners derive from the work of our microbiome. Without the full complement of microbes, that is, we humans are incomplete. And the consequence of being incomplete is the current epidemic of NCDs the world population is suffering from: obesity, autism, heart disease, asthma, and all the allergies and auto-immune diseases that plague many of us these days. Dietert quotes the World Health Organization to the effect that these NCDs now kill three times as many people as infectious diseases (68% to 23%). That’s because defects in the microbiome (occurring through drugs, diet, oversanitation, stress, and exposure to chemicals) lead directly to defects in the immune systems which determine what gets through to our cells, tissues and organs, and what does not.
            Is there scientific evidence that this is the case? Consider one study done by Derrick McFabe at the University of Western Ontario. McFabe demonstrated that simply by altering the concentration of one gut bacterial metabolite, the short-chain fatty acid known as propionic acid, he could make normal mice antisocial to the point where they ignored their littermates and obsessed on a ball. In the same vein, John Cryan and researchers at University College in Cork, Ireland, raised germ-free mice (bubble mice) and found that, lacking normal gut microbes, the mice had “altered gene expression” in the amygdala. They lack social cognition, are generally antisocial, and “have eerily similar social interaction profiles to those of autistic children” (247). As Dietert summarizes it, these metabolites (or products of bacterial metabolism), including such things as the vitamins B3, B5, B6, B12, and K, and critical brain chemicals like serotonin, dopamine, acetylcholine and norepinephrine, “can influence virtually every physiological system and tissue in the body” (70). They influence what we like to eat, whom we are attracted to, if anyone, and whether we can function normally or live our lives plagued by excessive inflammation leading to diseases like atherosclerosis. Again, as Dietert puts it, virtually every NCD (non-communicable disease), which is itself often due to loss of the full integrity of the microbiome, “has unhealthy inflammation with excessive oxidation at its core” (129).
            How does this happen, and why is it happening so much now? As noted above, modern conditions are major contributing factors to the compromising of our microbiome, our microbial partners. Dietert lists six factors contributing to the epidemic: 1) antibiotic overreach; 2) the food revolution and diet; 3) urbanization; 4) birth-delivery mode; 5) misdirected efforts at human safety; 6) mammalian-only medicine. Antibiotic over-use has received a great deal of attention in recent years, and many food producers have now cut back or eliminated the use of antibiotics in animal feed. But not all. And one of the areas where antibiotic use still reigns, as far as I can tell, is in its use to compensate for the obscene crowding that takes place in feedlots for cattle and in poultry cages. Disease cannot help but be rampant amid such intolerable crowding, and antibiotics are required to help keep diseases in check. In addition, doctors have routinely prescribed antibiotics for minor ailments like ear infections, and thus led to the compromise of not just the offending bacteria but to all the bacteria in and on our bodies. Use of probiotics like yogurt can help, but Dietert and others now recommend a major effort to limit the use antibiotics to only dire cases. One other area where antibiotics have been used routinely is in childbirth. Dietert makes much of the fact that Cesarean sections have increased exponentially in recent years, doubling and tripling in many countries. Today, Cesarean sections in the U.S. are up to 33% of all births, compared to 24% in England, 40% in parts of India, and 46% in China. One major result of this, according to Dietert, is that the newborn fails to get the contact with vaginal microbes that it needs to complete its own microbiome—so it is born incomplete. In addition, Cesarean sections run the risk of infection, so antibiotics are routinely employed pre-surgically, compromising the mother’s microbiome, and thereby her infant’s, even before birth.
            One other factor deserves mention here (though all of them are important). That is the role of chemicals with which our environment, our food, and our bodies have been flooded.  A simple thing like food emulsifiers (the chemicals that smooth things like ice cream, chewing gum, artificial tears), such as Polysorbate 80 and carboxymethylcellulose, have been “found to alter gut microbe populations by thinning the mucus layer and increasing inflammation” (167). In this experiment on mice, eventually the mucus thinning led to inflammation-driven NCDs in the mice. Bisphenol A, the infamous endocrine disruptor found in plastic baby bottles, food packaging and other plastics has also been found to compromise the gut barrier, again leading to increasing inflammation and NCDs. And that scourge of our planet, glyphosate, the chief agent in Monsanto’s Roundup pesticide, has been found to “selectively alter the ecosystem of environmental microbes (in the soil), such as favoring the formation of some types of biofilms” (256). This leads to reduction in the presence of some fungi needed by grass roots, which in turn leads to less foraging areas for ungulates. In a study of chicken gut microbes, pathogenic bacteria were found to be more resistant to glyphosate than were the helpful bacteria—thus helping the pathogens! And in Germany, glyphosate was found to affect the microbe mix in cows, reducing the normal protection their gut bacteria (Enterococcus) provided in restricting the growth of botulism spores. The result: an increase in botulism-related diseases in cattle in recent years.
            Enough said. Even if Dietert has overstated his case, it seems clear that a revolution in human health and food intake is under way. Dietert’s main recommendations call for a reduction in the flagrant use of antibiotics, a return to natural forms of childbirth where possible, and an increase in the use of probiotic foods. This gets to another point he makes: that traditional cultures, before the advent of cold food transport and frozen foods, used fermentation processes to keep foods from spoiling. Sauerkraut, kimchi, miso, tempeh, chichi, wines and beers, and of course yogurt were used by various cultures to keep foods edible, the side effect being that all of these foods have bacterial cultures that promote and restore the gut microbes we need to digest most of our foods. Some doctors have been for years recommending the use of yogurts after antibiotic treatment, precisely to restore the favorable gut fauna. Now Rodney Dietert’s book is providing the scientific rationale for even more attention to the microbes that foster our health and our very lives. It wouldn’t take much—except of course for the resistance sure to be mounted by industries like Big Pharma, which are quite content with the epidemics that keep millions sick and them wealthy. In that regard, we can expect lots of ‘scientific’ studies to prove that diseases like obesity, autism, asthma, and the rest are genetic. For myself, though, eating yogurt regularly and even preparing sauerkraut in my own kitchen seems like a much better option—until, that is, the world wakes up and outlaws GMOs, glyphosate, and Monsanto, and many others like them. At the least, it’s worth thinking about.

Lawrence DiStasi

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