Navigating the ‘gut-brain axis’ with a bacteria expert

19 Jul 2023

Image: Dr Claire Watkins

Dr Claire Watkins from PrecisionBiotics tells us about the benefits of friendly bacteria and how there’s so much to explore along the ‘gut-brain axis’.

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They might not be everyone’s cup of tea, but Dr Claire Watkins loves bacteria. She describes them as “so incredibly interesting and diverse” and is fascinated by how they “interact with each other in the body in different ways”.

“They can be that friendly neighbour, who provides that extra cup of sugar you need for your tea, or they can be competitive, especially when it comes to survival.”

Having grown up in “a household of very curious minds”, Watkins developed a love of science at a young age.

“Nothing could stop me from wanting to learn more about our bodies, the way they work and the way we interact with the environment around us,” she says.

She studied biology and chemical science at University College Cork and developed a passion for medical microbiology and microbial diversity. She pursued this interest by undertaking a PhD at the Teagasc Food Research Centre with Prof Catherine Stanton. Here, she “learned everything there is to know about the infant gut microbiome”. And it was here her interest in the relationship between the gut and the brain developed.

The gut and the brain

During her PhD, Watkins was based at the Science Foundation Ireland APC Microbiome Research Centre in Cork, “one of the world’s leading centres for microbiome research”, as she describes it.

“I spent my first two years focusing on what microbes we inherit at birth, where they come from, how they are passed down from mother to infant, what impacts their survival and what beneficial properties they possess,” she explains.

Microbes, or microorganisms, include bacteria, viruses, fungi and other tiny living things. Watkins quickly zoned in on bacteria as her microbe of choice.

“Only after learning first how these bacteria interact with one another, did I start to learn more about how they interact with our human cells in the gut and essentially interact with many systems in our body, including this relationship with our brain.”

The gut and the brain communicate with each other through multiple systems in the body. Watkins describes this as the “gut-brain axis” and says this interplay is essential to our overall health and wellbeing. And bacteria have an important role in this process.

“Bacteria in our gut can influence our central nervous system (the brain and spinal cord) bidirectionally via the vagus nerve, relaying information back and forth from internal organs in our body to the brain.

“One example … is through the production of chemical messengers, called neurotransmitters, which can help to regulate bodily functions, such as appetite, as well as our emotions.”

Applying this knowledge

These days, Watkins is product innovation lead at PrecisionBiotics, a Cork-based food supplement company that specialises in developing bacterial cultures to improve gut health.

“I’m very lucky to be in a position where I can help to innovate and develop new products containing these special bacterial cultures,” Watkins says.

“For me, learning about the challenges and all the right conditions that need to be met to produce a high-quality product with these special bacteria is a real eye opener. I started from working in the laboratory one day, to being involved in launching these new technologies into the market today. Every day you learn something new.”

Recently, PrecisionBiotics researchers were involved in the MicrobeMom project to study the transfer of gut bacteria from mother to infant, the results of which were published in the scientific journal Nature Communications.

At the time, Prof Fionnuala McAuliffe, who is a professor of obstetrics and gynaecology at University College Dublin and director of the Perinatal Research Centre, described the project as “significant and exciting”. The study’s findings could support the development of targeted probiotic supplements to boost the immune system, increase microbial infection resistance, fight disease and aid digestion.

Projects like this show the potential real-world impacts of gut research. As Watkins explains: “This research between our microbes, gut and brain is incredibly important to understand as we begin to unravel the overall impact it can have on our health and wellbeing.”

How to support your gut health

So, what does an expert like Watkins recommend we do to support our gut health? Unsurprisingly, she recommends that people eat more vegetables, fruits, wholegrains, beans, peas and lentils.

“These types of foods can be rich in antioxidants, but they can also fuel some of the bacteria in our gut which are important in helping to regulate physiological processes such as our endocrine and metabolic pathways, our immune system and our brain’s cognitive function, emotional state and wellbeing.”

Watkins describes herself as “a sucker for oats and high-fibre foods”.

“What I eat everyday continues to fuel my imagination in terms of what might be happening to the diversity of bacteria in my gut later that week.”

Whether you have a gut feeling, find an idea gut wrenching or get butterflies in your stomach, Watkins wants people to understand the deep connection between gut health and brain health. However, she stresses that “what’s happening in your body is still not fully understood”.

“Scientists are unravelling new information every day and it’s so important that we communicate clearly what is known and unknown so that people can paint a clear picture in their minds of how this impacts their choices; what they choose to eat, what food supplements they choose to take, how much exercise they decide to do and how they look after their health and wellbeing overall.”

Watkins says there are many ways to introduce friendly bacteria into your routine, but she urges people “to stay educated about what [they] are buying and look for articles by credible experts”.

Back to bacteria

In an interview with, microbiologist and principal investigator at APC Microbiome Dr Jennifer Mahony insisted that “not all microbes are bad”.

Watkins is definitely of a similar mind. She wants people to understand and appreciate the complexities of her favourite microbes, bacteria.

“Some are better at fermenting foods than others, some are optimal at digesting complex carbohydrates and fibres, others can have a beneficial impact on the human cells in your gut and produce metabolites or compounds with unique properties.”

Watkins’ passion for bacteria is undoubted and it’s evident she’s only getting started. “The more you think about it, the more questions you have and the more research ideas you want to explore. It’s a never-ending fascination!”

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Rebecca Graham is production editor at Silicon Republic