What's living inside your gut? Rather a lot! The gut is a universe of trillions of microorganisms known as microbiota, and collectively make up the microbiome. This microbiome is now best thought of as a virtual organ of the body.
It weighs about 2kg and is bigger than the average human brain. It’s made up of trillions of bacteria, archaea, fungi, and viruses, containing at least 150 times more genes than the human genome.
We are teeming with microbes, which form microbiomes on our skin, in our mouths, lungs, eyes and reproductive systems. But the gut’s microbiome is the largest, and its composition can vary per person. It also has an important role: it is thought that our microbiota stimulate the immune system, break down potentially toxic foods, and help to produce certain vitamins and amino acids.
Studies suggest that having a diverse population of gut microbes is associated with better health, and poor gut health is associated with a range of conditions, from obesity and brain diseases to depression and inflammatory bowel disease.
There’s been a lot of hype around how and what we eat, and how special diets can influence our gut microbes. What we know, is that dietary amounts of protein, saturated and unsaturated fats, carbohydrates, and dietary fibre can influence the abundance of different types of bacteria in the gut. According to research, the richer and more diverse the community of gut microbes are, the lower your risk of disease and allergies.
Read more:
- Do we get our gut bacteria microbiome before or after birth?
- Am I more bacteria than human?
- Dr Michael Mosley: Is fermented food really good for your gut microbiome?
- Put down the disinfectant: Should we be encouraging helpful bacteria into our homes?
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