What is the gut microbiome?

The gut microbiome (sometimes known as the gut microbiota) is the name used to describe the community of microorganisms living in our gut. We now know that our microbiome is absolutely essential for health and wellbeing – it’s being described by some researchers as a new and underappreciated organ. In fact, as well as improving our digestion, studies have shown that good gut-health boosts our mental health, immunity and can even help to keep the weight off. Read on to discover the secrets of the magnificent microbiome and how we can look after our good gut bugs…

What is the microbiome?

Microbiome is the term used to describe the trillions of microscopic organisms living in our body. These tiny tenants are mostly bacteria but also include beneficial viruses and fungi. Though we’ve learnt to associate bacteria, viruses and fungi with uncleanliness, infection and illness, the ‘good’ bugs that make up our microbiome actually work to keep these ‘bad’ bugs out.

The gut microbiome refers to the collection of bugs that have made their home in our gut, but mighty microbes can actually be found all over the body — in our mouth, eyes, vagina and on our skin, for example. Unlike genes, no two people have the same microbiome, even identical twins have a unique portfolio of gut bugs.

How does the microbiome develop?

Humans are born sterile — this means we have no beneficial bugs, microbes, viruses or fungi living in or on our body at birth. The birthing process, in all its messiness, is designed to transfer bacteria from the mother to her newborn baby. These first good gut bugs support the immune system and help the baby digest the sugars in breast milk — without our microbiome we wouldn’t survive our first few days on earth.

To learn more about how our microbiome develops, listen to Liz’s fascinating podcast with Professor Tim Spector.

Why do we need the microbiome?

Researchers are still at the very early stages of understanding the multiple roles of the microbiome. We do know, however, that the bacteria in our gut produce essential vitamins, amino acids and hormones, as well as helping to balance blood sugar, regulate appetite and protect other vital organs such as the brain and heart.

Studies are also showing that some gut microbes are more common in happy, healthy individuals, while high concentrations of less beneficial bacteria have been associated with conditions such diabetes, IBS, autism, obesity and anxiety, for example.

The research into gut health and mental health is a particularly booming field. With up to 90 per cent of our happy hormone (serotonin) produced in the gut, it’s now clearer than ever that our microbiome plays a crucial role in how we’re feeling.

Researchers also suspect that our microbiome can influence how we respond to medication. They hope that this might explain why some people find painkillers effective while others do not and why chemotherapy is tolerated well by some cancer patients and not by others.

Outside the gut, our skin microbiome is believed to help protect us from skin cancer, and the vaginal microbiome is known to be protective against infection.

How can we look after our gut microbiome?

While we have no control over our genetic make-up, the really good news is that we can shape our gut microbiome which has been shown to reduce our risk of certain diseases and improve overall wellbeing.

As a rule of thumb, a healthy gut microbiome is a diverse microbiome — it really is a case of the more the merrier! To increase the diversity of our microbiome we can ingest probiotics in the form of supplements or fermented foods such as kefirkombuchakimchisauerkrautsourdough and live yoghurt. Probiotic supplements and fermented foods contain live strains of bacteria that can colonise our gut microbiome, increasing its diversity. 

We can look after the good gut bugs we already have by feeding them with PREbiotics (not to be confused with PRObiotics). Once again, there are supplements available but prebiotics also include fibrous foods such as wholegrains, legumes, vegetables, fruits, nuts and seeds. We might not be rushing to try it any time soon, but a new study has shown that eating crickets and other insects can also increase our gut diversity. 

Our favourite gut-friendly recipes include our broccoli and kefir dipfibre-packed, Peruvian borlotti bean salad; and fermented kombucha cocktails.

By Ellie Smith