Microbiome image courtesy of Steve Gschmeissner
The human microbiome consists of the bacteria, viruses and fungi that live in or on our bodies. The 100 trillion microbe cells in the microbiome outnumber our human cells by ten to one, but because the microbes are so small we are still about 98% human by weight.
Different parts of our bodies – gut, skin, nose, armpit, throat, and so on – have different ecosystems of microbes. Each person’s microbiome of about 500 species is unique, like a fingerprint: even identical twins have different microbiomes.
Although we traditionally think of “bugs” as being bad, we need our microbiome to make certain nutrients, such as Vitamins B and K; to crowd out disease-causing microbes; and to help our immune systems to develop normally.
The upsurge in interest in the microbiome in the past few years is due to the invention of new techniques for sequencing the DNA and RNA of microbes. Earlier methods could only identify about 1% of the microbiome, making it a “black box” for researchers until now.
The new techniques for identifying microbes have led to the microbiome being called “the forgotten organ” and, like any organ in the body, it can go wrong. Problems with the microbiome are being linked to diseases including inflammatory bowel disease and Type 2 diabetes.
The promise of a microbiome approach to disease is shown by its success in treating the potentially fatal superbug C. difficile by means of a fecal transplant: essentially, a mini-microbiome transplant. The procedure involves seeding the gut of a patient with a transplant of fecal matter from a carefully-screened healthy person. A clinical trial of fecal transplants for persistent cases of C. difficile was stopped early because the transplants were far more effective than conventional treatment with antibiotics.
The microbiome is a new frontier in medicine and may play a part in many serious diseases, including ME/CFS. This is an area of study whose time has come.