Dr. Buğra Buyrukçu

Microbiota

Microbiota is a term that describes all microorganisms that live in/on our body and do not harm us. Skin, mouth, bowels, respiratory tract, genitourinary tract are among these areas which host bacterias, viruses and fungi.

The word microbiome, developed by Joshua Lederberg, is the genome of these microorganisms that form our microbiota.

The amount of microbiota in human body is 8-10 times greater than the total number of its cells and weigh 1-1.5 kg in total, so one can wonder if microbiota lives in us or we are living on a microbiota. The majority, as much as 70%, lives in the gastrointestinal tract, with more than 500 species in the large intestine and occupying a surface of 400 square meters, as big as a tennis court.

What impacts do you think this large group has on our body? Studies have shown that long term chronic diseases are caused by these microorganisms. Everard and colleagues published an article in mBio magazine in 2014, showed that regular functioning of the digestive system affects many systems, including immune system balance, supply of energy cycle, lipid and carbohydrate metabolism, brain functions, happiness and predisposition towards depression. In other words, many health problems, including weight gain and the inability to lose weight despite diet, are caused by the imbalance of these microorganisms, therefore first symptom of all these diseases is constipation or diarrhea.

Bifidobacteria and lactobacillus are the most useful bacteria (probiotics) in the large intestine. Apart from these, bacteroids, Clostridia, Escherichia coli, Enterococcus, yeast and mold species are most commonly found microorganisms in the intestines.

Constipation is a very important health problem that needs to be corrected.

The population of microorganisms, which is described as a ”'new organ/super organ” in Ciorba's Clinical Gastroenterology Hepatology, has metabolic, immunological, neuroendocrine and hormonal duties. Many vitamins and amino acids which are not present in our body are synthesized in our microbiota. 10% of an individual's daily energy is produced by these bacteria. Macpherson demonstrated that gastrointestinal microbiota is directly related to the immune system. Modulation of immunity, neuromotor functions and mucosal barrier function is directly associated with these microorganisms.

The bacterial flora in the gastrointestinal tract shows personal differences and has individual characteristics like fingerprints. Factors that constitute this specifity are type of delivery (vaginal or caesarean section), maternal vaginal or intestinal flora, postnatal diet (breast milk, feeding), flora of the environment, eating habits of the family. Individual permanent flora occurs in the first three years, following this, the dietary habits of the individual and the environmental conditions shape the flora. Therefore the first three years of life will be the determinant of future diseases.

The deterioration of the equilibrium between beneficial and harmful bacterias in the large intestine leads to breakdown of intestinal barrier and formation of excessive permeable bowel which predisposes many chronic diseases. This permits the migration of heavy metals and toxins into the blood, stimulates the immune system and leads to abnormal responses towards body cells (autoantibodies), giving birth to chronic diseases. An article published in Physiology Review in 2010 by Sekirov and colleagues describes the mechanism of microbiological changes causing diseases.

How does bacterial dominance occur in intestinal flora? The answer to this question is the developing technology in recent years and industrialization. We have been living in a more hygienic environment compared to the past, we consume food with shelf life, frozen products and instead of seasoned fruits and vegetables we eat those grown in greenhouses. The use of antibiotics has increased considerably and strong antibiotics have become the first choice because of antibiotic resistance. Agricultural pesticides are used a lot more and carried to our tables along with food. Increased use of fertilizers and genetically modified products (GMOs) are other problems. On top of these we use disinfectants to clean our food, ingest the dyes added to food, so our intestinal floras have changed in favor of malignant bacteria that disrupt the bowel barrier. In countries that adopted the Western lifestyle, chronic disease and cancer rates have increased significantly in the last 50 years. The study of Pall Martin published in Acta Physiologica Sinica-2015, listed the increasing chronic diseases as  Type 2 diabetes, rheumatic diseases, bowel diseases, allergies, skin diseases, acne, depression, Parkinson's disease, multiple sclerosis and Alzheimer. In 2007, Palmer and colleagues reported that babies fed with formula had low Bifidobacteria and higher aerobic bacteria colonization in infants respect to those fed with breast milk, and a high incidence of childhood asthma and allergic disorders was observed in these babies.