How your internal microbes can keep you healthy

Illustration of a human gut

11 June 2020

There is a vast community of bacteria, viruses and fungi living on your body right now; collectively they are known as the human microbiome; they have hugely greater complexity than the human genome itself. The microbiome, which mostly lives in the gut, plays an important role in immunity, defense against pathogens, increasing availably of nutrients to the host (that’s you and me), and even influencing health and behaviour. Although how the microbiome affects our health and behaviour (or vice versa) is not particularly well understood.

Dr Kaitlin Wade, who was a Research Associate at the Integrative Epidemiology Unit at the University of Bristol, used an Early Career Fellowship grant from the Elizabeth Blackwell Institute to develop a greater understanding of both the impact of what we eat on the gut microbiome and how this can alter health.

Mendelian randomization

Dr Wade used a type of study design called ‘Mendelian randomization’, which uses genetic variation to better understand the causal links between traits of interest (such as diet) on outcomes (such as the microbiome). It is useful because genes aren’t affected by other factors - for example, other behaviours related to the traits you’re looking, which might have an effect, but are hard to control for.

“I use these models to understand the causal role played by the human gut microbiome in different health problems”, said Dr Wade. “These include obesity, colorectal cancer, type 2 diabetes and inflammatory bowel diseases.”

“This fellowship has given us a greater understanding of the impact of human genetics on the gut microbiome,” she continued. “As well as evidence that variation in the gut microbiome may be causally related to various health problems such as obesity and colorectal cancer, my work has also contributed to the understanding of how to integrate epidemiology and microbiome research, which will be of increasing importance in the future”.

Publication, preparation and presentation

Dr Wade’s work on the impact of the gut microbiome on health, and her methodologies, have been accepted for publication in several journals including Nature Microbiology, Lancet Psychiatry and Wellcome Open Research with more in preparation. She has also been invited to present her work at several national and international conferences and has been part of engagement activities with the general public, schools and media, as well as establishing a variety of collaborations and partnerships which she plans to carry forward.

Early Career Fellowships are designed to support early-career researchers as they develop towards independent research careers. As well as her research and collaborative efforts, Dr Wade was able to make progress with applications for fellowships, teaching and public engagement within a milieu designed to foster academic growth. Indeed, Dr Wade has started a Lectureship at the Bristol Medical School, and is co-director of the MSc in Epidemiology.

“The Elizabeth Blackwell Institute has been wonderful at making me feel part of a cohort,” said Dr Wade. “The members of the Institute clearly work really hard to bring us together, providing training opportunities to its fellows and welcome/social events. Knowing the cohort has been very helpful and I have felt very supported throughout this whole process.”