The estimated 1.3 trillion bacteria in our intestinal tract is collectively called the microbiome. Like phytonutrients, most people are unaware of its importance in health. Most experts studying this new frontier in health are showing strong evidence that Hippocrates was correct in saying ‘all disease begins in the gut’. There are many kinds and families of gut bacteria, (over 1000 species) and most are living in our colon, but bacteria also populate the other areas of gi tract in mouth, even stomach, duodenum , jejunum, and ileum but to a much lesser degree. Microbes are all over our skin. The gut/colon microbes have major interactions with our body so much that it is called an essential organ and a ‘second brain’. Thousands of different strains of bacteria, viruses, and funguses are present and populations vary greatly with our diet. They produce millions of biomolecules, of which 30-90% are unknown. They interact with our immune system in beneficial or in deleterious inflammatory ways. Most of these microbes are beneficial and friendly to us. It is a vast ecosystem delicately balanced but can be severely disrupted by contaminated foods, antibiotics, and poor dietary choices. These bacteria feed on the undigested vegetable fibers from the food we eat. If we eat mostly whole plant foods, we supply a rich supply of fibers that allow the most beneficial types of bacteria (like Provetello, bifidobacterium, lactobacillus) to flourish. With these high vegetable fibers, they produce chemicals that benefit our bodies, especially the short chain fatty acids like butyrate which is the best energy food source for our gut enterocytes that are responsible for the integrity of our intestinal barrier.. These gut microbes seem to be in communion with each other and secrete chemicals to eliminate harmful inflammatory bacterial pathogens that would harm our bodies. So these friendly bacterial homesteaders also modulate with our immune system to recognize which strains are beneficial and to be protected, and which are to be attacked and destroyed. If we eat the Western Diet of processed foods, animal products and dairy, not much fiber or micronutrients are supplied and the bacterial populations change to less desirable and inflammatory species. Our intestinal lining is made up of mostly one layer of columnar cells, covered by a thick mucus which is secreted by these enterocytes. Underneath this lining lies a rich vascular system of capillaries to absorb nutrients interspersed with such a great array of immune and nerve cells. 70-80% of our immune system is located here. Hippocrates said ‘all disease begins in the gut’ for a good reason: our gut encounters more compounds and potential antigens in one day than the rest of our body would see in a lifetime. Different bacteria in our microbiome interact differently with our body’s immune system, metabolism, and with ingested pathogens. What we are eating determines its’ makeup and diversity. The science of the microbiome is a vast frontier that is just being explored, and not all understood yet but much has been learned over the past 20 years, not known to the previous scientific community. Certain bacteria species such as Lactobacillus and Bifidobacterium are more favorable to our gut and flourish with ingested whole plant foods. They feed on such undigested fibers that our body does not digest. They digest and break down the undigestible fibers and secrete many small chemicals that are absorbed into our body. Some very important of these are short chain fatty acids like butyrate acetate, and propionate which our intestinal lining depends upon for fuel. Such fuel promotes a strong intestinal barrier, where no leaking occurs and a thick mucus barrier is produced by the goblet cells in the lining. Other chemicals secreted by a healthy microbiome have been shown to be absorbed from the colon and circulate in our bodies and influence other organs beneficially such as our brain and our mood. The mucus barrier that overlays our intestinal lining becomes thicker and healthier when we feed a high amount of plant fibers to our microbiome bacteria. This thick mucus barrier keeps our intestinal lining and immune cells from becoming inflamed and agitated. Experiments have shown that when a typical low fiber Western diet is consumed (about 8-15 gms/fiber/day), the microbes suffer and start to digest the mucus barrier, causing inflammation and activating immune cells and cytokines. Whole plant based diets supply 35-55 gms/day/fiber and so feed the microbes, which feed our intestinal lining cells, which produce abundance of the protective mucus lining: thus preventing the inflammatory cascade. A diet low in fiber and phytonutrients from mostly animal products, processed foods, and dairy promotes growth of less beneficial and inflammatory populations of microbes. The high content of sulfur containing amino acids methionine and cysteine in animal and dairy promote bacteria that produce hydrogen sulfide, the rotten egg smelling gas, which is also inflammatory and destructive to intestinal cells and reduces production of its protective mucus layer. The prevailing theory on the origin of all the auto-immune diseases begins with damage to our gut lining. : The latter mentioned foods tend to harm the gut lining by their inflammatory and oxidative promoting properties: this causes separation of the intestinal cells whereby peptides , bacterial products (called lipopolysaccharides or endotoxins) and other compounds leak into the underlying vascular network. Here they encounter our immune cells that recognize them as foreign invaders and form antibodies against them to destroy them. These immune cells circulate in the body and sometimes the antigen-recognizing pattern they carry interacts with some part of our own bodies makeup, so that ‘friendly-fire’ happens, where we now injure ourselves. We know this happens in type 1 diabetes, hypothyroidism, rheumatoid arthritis, celiac disease, and likely in all the others like multiple sclerosis. Many people suffering from auto immune diseases have also gastrointestinal dysfunction and symptoms. The reason the microbiome is called our ‘second brain’ is because changes here strongly affect mental health and serotonin levels. So the beginning of therapy is aimed at repairing the leaky gut starting with the right diet of whole plant foods and eliminating the other toxic anti-inflammatory foods.
Also, it is well known that a healthy diverse microbiome obtained from having diet mostly whole plant foods provides best protection against infections and epidemics. In our age of Covid-19 epidemic, best immune protection comes from eating these whole plant foods. There are over 300,000 edible plants available for us; all of them contain plant fibers and phytochemicals that our gut microbes feed on and prosper and produce the short chain fatty acids and other chemicals beneficial to our whole body. They are key in forming our immune system, neutralizing toxins, preventing growth of unfriendly pathogens that we ingest, and keeping our intestinal barrier intact from attacks and damage. (2, 12, 13, 36, 39, 43, 44, 45, 49, 54, 59, 61, 64, 71, 84, 85, 91,106, 126, 129 136)
Blue Zone Observations.
Blue zones are specific areas around the earth where certain populations of people live much longer and healthier lives than others. One example is Okinawa Japan, where they have high percentage of active, healthy people living more than 100 years. Two other examples are the island of Sardinia, Italy, and the Seventh Day Adventist Population in California. These populations all eat a predominantly a whole plant-based diet of vegetables, fruits, legumes, nuts and mushrooms. There is no blue zone or longevity zone ever found where they eat a predominantly animal , dairy, or keto diets. Some may occasional seafood or meat, but this on rare occasions and less than 5% of calories . They do eat the healthy fats found in olives, avocados, nuts and seeds. They use lots of spices such as turmeric oregano, parsley, thyme, etc. Most get regular exercise, good sleep, and are not overweight. This observation along with many animal studies confirm the healthy longevity benefits of whole plant food.
