Role of The Gut Microbiota in Nutrition and Health

Microbiome refers to the collective genomes of the micro-organisms in a particular environment, and microbiota is the community of micro-organisms themselves.

Approximately 100 trillion micro-organisms (most of them bacteria, but also viruses, fungi, and protozoa) exist in the human gastrointestinal tract—the microbiome is now best thought of as a virtual organ of the body.

The human genome consists of about 23 000 genes, whereas the microbiome encodes over three million genes producing thousands of metabolites, which replace many of the functions of the host consequently influencing the host’s fitness, phenotype, and health.

Key messages

  • Gut microbiota influences many areas of human health from innate immunity to appetite and energy metabolism
  • Targeting the gut microbiome, with probiotics or dietary fibre, benefits human health and could potentially reduce obesity
  • Drugs, food ingredients, antibiotics, and pesticides could all have adverse effects on the gut microbiota
  • Microbiota should be considered a key aspect in nutrition; the medical community should adapt their education and public health messages
  • Fibre consumption is associated with beneficial effects in several contexts

The BMJ: Role of the gut microbiota in nutrition and health