MICROBESIN YOUR BODY
Did you know that you have more microbial cells than human cells in your body? astoundingly, for every cell in your body, there are ten microbial cells. That’s as many as 100 trillion microbial cells, which can collectively account for anywhere between 2 and 6 pounds of your body weight! a microbe is any living thing that cannot be seen with the naked eye (for example, bacteria, viruses, fungi, and protozoa). The total population of micro-bial cells on the human body is referred to as the microbiota, while the combination of these microbial cells and their genes is known as the microbiome. The micro-biota includes so-called “good” bacteria that do not cause disease and may even help us. it also includes pathogenic, or “bad” bacteria.
With that many microbes in and on our bodies, you might wonder how they affect our health. To answer that question, in October 2007 the national institute of health (nih) initiated the 5-year human microbiome Project, the largest study of its kind. Five significant regions of the human body were examined: airway, skin, mouth, gastrointestinal tract, and vagina. This project identified over 5000 species and sequenced over 20 million unique micro-bial genes.
What did scientists learn from the human microbiome Project? human health is dependent upon the health of our micro-biota, especially the “good” bacteria. in fact, it seems that our microbiota are so completely intertwined with human cells that in a 2013 New York Times article, Dr. David relman of Stanford university sug-gested that humans are like corals. Corals are marine organisms that are collections of different life forms all existing together. more specifically, the human microbiome is intimately involved in the development and maintenance of the immune system. and more evidence is mounting for a correlation between a host’s microbiota, digestion, and metabolism. researchers have suggested that microbial genes are more responsible for our survival than human genes. There are even a few consistent pathogens that are present without causing disease, sug-gesting that their presence may be good for us. however, there does not seem to be a universal healthy human microbiome. rather, the human microbiome varies across lifespan, ethnicity, nationality, culture, and geographical location. instead of being a detriment, this variation may actually be very useful for at least one major reason. There seems to be a correlation between certain diseases and a “charac-teristic microbiome community,” especially for autoimmune and inflammatory diseases (Crohn’s, asthma, multiple sclerosis), which have become more prevalent. Scientists are beginning to believe that any significant change in the profile of the microbiome of the human gut may increase a person’s susceptibility to autoimmune diseases. it has been proposed that these changes may be associated with exposure to antibiotics, particularly in infancy. Fortunately, newer studies of microbial transplantations have shown that the protective and other func-tions of bacteria can be transferred from one person to the next. however, this work is all very new and much research remains to be done.
Throughout the remainder of this text, we will highlight specific instances where our microbes influence our body systems. in light of the importance of our body’s bacteria and other microbes, the preva-lence of antibacterial soap and hand gel usage in everyday life may be something to think about.