That question was central to the 2024 'GEEF care about your gut' study (Gut Health Enhancement by EatingFavorable Food), by VU University Amsterdam and Wageningen University in collaboration with the MDL Fund.This study will now be followed up with the large-scale study 'Feed Your Microbes', in which the VU will again collaborate with the MDL Fund. Dietician and VU alumnus Marieke van de Put was involved in the GEEF study. She explains why this follow-up study is so important.
Tell us again: what was it again about those gut microbiomes and healthy food?
"A healthy gut microbiome is super important for a properly functioning immune system. Those gut microbiotics convert dietary fibre into 'short-chain fatty acids' , among other things, which regulate our immune system, cholesterol and blood sugar levels.There is also a clear link between the gut microbiome and chronic diseases, such as inflammatory bowel disease, obesity and type 2 diabetes. But we also see a link with gut health in some types of cancer and cardiovascular disease. All health risks and healthcare costs that we can positively influence with healthy eating."
Your research showed that a specific diet produces a better gut microbiome?
"Yes. In the GEEF study, people were given a high-fibre diet, or a diet with fermented products - think cottage cheese, kimchi, kombucha. All based on products that are easy to find in shops. After eight weeks, we saw a real difference - the 'fermented' group showed an activation of the immune system, and in those over 50, the microbiome became more similar to that of younger participants.
The fibre group showed an increase in health-promoting bacterial species, and surprisingly, they reported better sleep! The beauty was: we linked the results back to the participants with explanations, and after three months, people in the intervention groups were still eating healthier.
So we observed that creating awareness, together with easy-to-follow dietary advice, makes a healthier lifestyle possible. I see this reflected in my practice as well, where I guide people towards a predominantly unprocessed, plant-based diet, i.e. rich in fibre. And I see that awareness helps to maintain that diet."
What does the 'Feed Your Microbes' study add ?
"The GEEF study is now being scaled up to a study with at least 10,000 participants. These will be given the diet of high-fibre or fermented foods, and an app that gives them instant feedback on their gut microbiome via a picture of their stool. This motivates people to permanently adjust their diet.
An interactive exhibition on gut microbiotics is currently running in Artis/Micropia. There, we hope to raise awareness and interest people in participating or donating to the research. And hopefully that will eventually give input back to the MDL Fund, doctors and dieticians. This will bring us closer to the original goal: making the Netherlands healthier!"
