Gut Microbiome Diversity Linked to Fruit and Vegetable Consumption

In a comprehensive study, a team of researchers from TU Graz’s Institute of Environmental Biotechnology has presented compelling findings supporting the idea that the intake of fruits and vegetables enhances the diversity of bacteria in the human gut.

The diversity of bacteria in the gut holds significant significance for human health. It is well-established that a substantial portion of the maternal microbiome is transmitted to the newborn during childbirth, and a similar transfer occurs while breastfeeding via breast milk.

Other sources of this diversity remained largely uncharted until recently. A team led by Wisnu Adi Wicaksono and Gabriele Berg, affiliated with the Institute of Environmental Biotechnology at Graz University of Technology (TU Graz), has now successfully demonstrated that microorganisms derived from fruits and vegetables contribute to the composition of the human microbiome.

The researchers reported this in a study in the journal Gut Microbes.

You Are What You Eat

The researchers successfully illustrated that both the frequency of consuming fruits and vegetables and the variety of plants included in one’s diet have a notable impact on the presence of fruit- and vegetable-related bacteria within the human gut.

Early childhood, in particular, represents a critical window for the introduction of plant-associated bacteria. Their study also unveiled the probiotic and health-enhancing characteristics of these plant-derived microorganisms.

A microbiome encompasses the collective assembly of all microorganisms inhabiting a larger organism, such as a human, animal, or plant, or a specific part of them, like the digestive system or a piece of fruit. While our understanding of individual microbiomes is expanding, the interconnections between them remain relatively unexplored.

The proof that microorganisms from fruits and vegetables can colonize the human gut has now been established for the first time.”

Wisnu Adi Wicaksono, Study First Author, Graz University of Technology

These findings imply that the consumption of fruits and vegetables, particularly during infancy, exerts a favorable impact on the maturation of the immune system within the initial three years of life, a period marked by the formation of the intestinal microbiome.

Moreover, even beyond this critical early stage, maintaining a rich diversity of gut bacteria continues to offer health benefits and enhance resilience.

It simply influences everything. Diversity influences the resilience of the whole organism; higher diversity conveys more resilience.”

Gabriele Berg, Institute Head, Graz University of Technology

Several Billion Sequences

To establish a direct link between the consumption of fruits and vegetables and their impact on the intestinal microbiome, the research team initially compiled a database of microbiome data from various fruits and vegetables, enabling them to identify their specific bacterial profiles.

They then compared these profiles with publicly available data from two separate studies on gut flora. The first, the TEDDY project, focused on the long-term development of infants, while the American Gut Project examined the intestinal microbiome of adults. Both projects also collected information regarding the dietary habits of their participants.

In total, the researchers had access to metagenomic data from approximately 2,500 stool samples, each of which contained between one and ten million genetic sequences, resulting in the evaluation of several billion sequences.

This extensive dataset allowed them to conclusively demonstrate the presence of microflora from fruits and vegetables within the gut. This evidence represents a crucial step in supporting the WHO’s One Health concept, which intricately connects human, animal, and environmental health.

Follow-Up Study on Three Continents

To gain a deeper understanding of this relationship, Gabriele Berg, in collaboration with international counterparts and as part of the EU-funded HEDIMED project is currently engaged in an intervention study.

In this study, individuals across three continents are consuming identical diets for a specified period, after which their waste materials are subjected to detailed analysis.

Furthermore, beyond the scope of this study, Gabriele Berg envisions numerous domains that could be influenced based on the study’s outcomes. This influence extends to food production, given that soil quality, fertilizers, and pesticides all have an impact on the microbiome of plants.

Fresh fruit and vegetables will always have the best microbiome; agriculture or processing companies already have a major influence here. And the storage and processing of food must also be critically reconsidered. Every fruit and vegetable has a unique microbiome. So maybe at some point a personalized diet can be put together based on that.”

Gabriele Berg, Institute Head, Graz University of Technology

Based on the results anticipated from the forthcoming study, there may be intriguing possibilities for individuals.