SLU news

Fibre-rich bread for a healthy gut and brain

Published: 29 March 2021
A woman with blond hair in a ponytail stands in a laboratory with a bottle in her hand. Photo.

Laura Pirkola investigates the effects of fibre-rich bread on gut microbiota and the brain with human studies. She is also studying health communication and behavior on this topic. Laura is now halfway through her PhD project and we took the chance to ask her some questions!

What we eat affects our gut microbiota and our brain via a complex communication system between gut and brain. Rye and oats are both rich in dietary fibre and polyphenols, components known to affect gut microbiota.

From gut, to brain, to communication

Laura is studying the effects of fibre-rich bread on gut microbiota and the brain in her PhD project. In addition, she is studying health communication and behavior on this topic. The project is part of LivsID, SLU’s industrial PhD students within the food research area.

Laura did her master’s thesis at the University of Helsinki on bread and gut health in collaboration with Fazer. After this, she worked two years at Fazer’s research and new business development unit before starting this PhD project.

– My PhD project consist of three research studies, and I’ll hopefully be ready with the manuscript for the first one by summer. The study title is “In vitro fermentation of rye, oat and wheat bread with fecal material from two donors with different microbiota composition”, says Laura.

Fun and exciting to work with human subjects

– Now I’m in Örebro University working on a human clinical trial that studies the effects of fibre-rich bread on the gut-brain axis. It is an exciting study and it’s fun but challenging to work with human subjects!

The clinical trial will keep Laura busy at least for the rest of the year. First, all 34 participants need to complete the intervention where they eat bread for three weeks and different measurements are before and after that period. After that, there is lab work and data analysis to complete.

– Then the plan is to conduct one more study and that is a health communication study in collaboration with Uppsala University. We want to find best ways to communicate the health effects of whole grain to consumers and to increase their whole grain and fibre intake. 

Short-chain fatty acids important for gut-brain communication

– The results of the in vitro fermentation study indicate that gut microbiota composition affects the fermentation process. For example, the production of short-chain fatty acids, that have many effects on health, play also an important role in the gut-brain communication. It would be exciting if we could see similar results in the on-going clinical trial. 

Doing a PhD during a pandemic cannot be easy. Have you had any problems in the project?

– The covid-19 pandemic has challenged the project timetable and there have been some delays in the studies. It’s not the easiest time to work with human studies but it’s great that we’ve been able to work at all – in many other countries clinical studies have been on hold because of the pandemic. 

A new research field

Gut microbiota and the gut-brain axis is still a quite new research field, who will benefit from the results of this project?

– As it is a new field, all research on the topics is valuable, especially randomized controlled trials. Outside of academic world, I think the results can be of interest for food industry, probiotic and prebiotic producers, and other companies producing functional products. The results of the health communication study could be interesting for different public health actors. 

What will happen after you have completed your PhD? Do you have any plans?

– My plan is to work with research and/or product development or something related at Fazer. I think it would be great to be involved in the development of foods or other products than can improve human health. It might also be nice to do a post doc, but at least now, it feels like I am more interested in working in the industry than in academia. 

Doing a PhD without losing the connection to industry

– I think gut microbiota is a very fascinating topic, so doing a PhD about it is very cool! This project was a unique opportunity: to do a PhD without losing the connection to industry, to research something this interesting and relevant, and also a great chance to move abroad. 

When Laura is not working, she spends time with her boyfriend, and when possible, with friends and family.

– My dearest hobby is sport climbing, and I like also to spend time outdoors walking, running or hiking, cook and listen to audiobooks, concludes Laura.


LivsID is an industry PhD-program at SLU, dedicated to research and education within food-related topics. The program involves nine companies and seven departments at SLU. The industrial PhD students are employed by the company where the project is based and conducted research in food-related applied areas. Through LivsID's activities, they also interact with each other and create a network between academia and companies. 

The program was initiated with support of the government as part of the National food strategy and established in autumn 2018 with initially 10 projects. One more project is associated. The program is running in Alnarp, Umeå and Uppsala.

Read more about the LivsID program here.


Portrait photo of a woman with long hair. Photo.

Laura Pirkola
Industrial PhD student at SLU and Fazer