Diet And Gut Microbiota

Implications in Health and Disease.

- Sadhna Sharma

The human body hosts more microbes than body cells. All human-associated microbes are collectively known as microbiota and the microbiota encoding genes form the microbiome. Gut microbiota also called gut flora is the name given to the microbe population living in our intestine. Our gut microbiota contains tens of trillions of microorganisms, including at least 1000 different species of known bacteria with more than 3 million genes. In fact, it contains ten times more cells than the human body and 150 times more genes than the human genome.

One-third of our gut microbiota is common to most people, while two-thirds are specific to each one of us. In other words, the microbiota in our intestine is like an individual identity card. Although more than 1,000 different known bacterial species can be found in human gut microbiota, only 150 to 170 predominate in any given subject.

About 50% of the fecal mass is made up of bacteria. This population is composed of trillions of microorganisms that belong to 4 main groups: Firmicutes, Bacteroidetes, Actinobacteria, and Proteobacteria, with 90% predominance of the first two. Each one of us has a unique microbiota but it always fulfills the same physiological functions with direct impact on our health.

Introduction to Gut microbiota

The gut microbiota consists of bacteria, archaea, fungi, protozoa, and viruses. The microbial communities interact with each other and with their host, causing influence on the physiology and health of the host. It can weigh up to 2 kg and is described as the biggest endocrine organ of the human body as it is responsible for the synthesis of several metabolites which act as hormones.

Some of the functions are: