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Interview with Ruth Ley, Otto Bayer Awardee 2020

In the 2000s, Ruth Ley helped establish microbiome research. Today, she is one of the world’s leading scientist in her field and received the 2020 Otto Bayer Award for her pioneering work. In an interview she shares her enthusiasm about bacteria that impact how fit, healthy, and happy we are.



Professor Ley, what makes microbes such a hot research item?

It’s their win-win relationship with us. We used to think that human bodies are all about organs and cells. Then we discovered that our skin and guts provide the ecosystem for trillions of non-human organisms. And we discovered another interesting thing: we are not born with these bacteria. They start to colonize us at birth, and by the time we are adults, our personal microbiome is as unique as a finger print. And then, over the past 15 years we have been looking with increasing awe into all the things they can do for our physical and our mental health.




What is the focus of your present microbiome research? 

We want to know HOW they do it: how these bacteria impact our body functions and processes; how they affect our weight, our fitness, our brains; how they trigger alarm to summon our immune system; and how they adapt and evolve in new environments. We want to understand what goes wrong with the microbiome when people acquire autoimmune disorders and we hope to find out how these microorganisms can play a role in managing a whole range of diseases, including cancer.




Has your research also revealed how we can protect our microbiome?

Yes, in fact it has, but protection is not enough: we need to restore it! In the past decades, the Westernized world has damaged our microbiome and thinned its diversity: drugs such as antibiotics play an important role here. Did you know that adults in the US eat 40 courses of antibiotics in their lives? And every time they do, they wipe out a large part of their microbiome. Then, secondly, there is the hygiene factor: even though hygiene is a blessing in many ways, it has also reduced our microbe diversity, because it cuts down on the transmission of hostile, but also of friendly bacteria. And thirdly, there are our eating habits...




How does food impact our microbiome? 

Whole-grain food provides a steady flow of fibers to keep the gut microbes nourished and happy. In the Westernized world however, we tend to eat “pre-digested”, refined foods: the fibers get chopped up outside our body before we eat it. As a result, our microbes are starving and can no longer help us to stay healthy and fit. One of the missions of my research is to find out how we can keep the gut microbiome balanced and make it work for us.




Prof. Dr. Ruth Ley

There is so much still to find out!

You helped to establish this field of research 15 years ago. What triggered your interest?

My first scientific projects involved the environment. In a NASA project, I studied soil microbes in the Mexican desert. At the time, people expected microbial life to be simple – both here on earth, and on other planets. But they are not. On the contrary: our project team discovered myriads of unknown microbe types: it was a whole ecosystem that was off the charts. And we mapped it! This experience had me hooked.




And how did you then move from mud & soil to medicine?

It was a big gamble. I knew nothing about medicine, humans, or the immune system. Then I read about a gastroenterologist, Jeffrey Gordon, who had pioneered studies with the gut microbiome of mice. That was exciting. I joined his lab and soon we were the first to prove that the microbiome was a cause of obesity in mice. In 2006 we published a catalyst paper and then the microbiome field blew up. Subsequently, there was an explosion of discoveries and the field is still growing. There is so much still to find out!




In 2020 you received the Otto Bayer Award for your work. What does this distinction mean to you?

I am delighted to see that my area of research is recognized as a mainstream scientific topic now. I was not always sure that it would be accepted by the medical sciences. The award puts microbiome research in the limelight and I think we can expect important new treatments to result from it.




What drives you in your scientific mission?

The process of creativity and discovery: the creativity to imagine a connection that other people have not seen. You look at data that don’t make sense and ask yourself: How could they make sense? You start testing. Then you look at the results, and WOW, it is like you imagined! And you are the first person to see this new discovery. That’s what brings about jumps in science. And that is what drives researchers all over the world.



Ruth Ley presenting at the Otto Bayer Award Ceremony


Otto Bayer Award 2020

YYMMDD Author/Uploaded by

Presentation by Ruth Ley


Interview: Gabriele Schmitt-Bylandt

Photo Credit: Prof. Dr. Ruth Ley


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