By comparing the bacteria in fruits and vegetables with those in the human gut, researchers have shown for the first time that consuming fruits and vegetables has a positive effect on the bacterial diversity of the gut microbiome. Bacterial diversity in the gut plays an important role in health. The human microbiome figures prominently in research, with links to cancer, personality, memory, and diseases such as diabetes and multiple sclerosis.
It is known that the mother's microbiome is transferred to the baby at birth and is enhanced through breastfeeding, so what other sources of gut bacteria are there? A new study by researchers at Austria's University of Technology Graz (TUGraz) confirms for the first time that fruits and vegetables are one source.
"Now, for the first time, evidence has been demonstrated that microorganisms from fruits and vegetables can colonize the human gut," said Wisnu Adi Wicaksono, first and corresponding author of the study.
The microbiome is the sum total of all the microorganisms, both good and bad, that colonize all or parts of larger organisms such as us, animals, and plants. In the current study, the researchers first created a catalog of microbiome data from 156 types of fruits and vegetables. They then compared these data with data from two studies on human gut flora: one study looked at the microbiome of infants and the other looked at the microbiome of adults. Both studies also collected information on participants' food intake.
Both human studies provided metagenomic data from approximately 2,500 stool samples, allowing researchers to evaluate billions of sequences. From this extensive data set, they were able to demonstrate the presence of fruit and vegetable microbiota in the human gut, with fruit- and vegetable-associated bacteria accounting for an average of 2.2% of the overall bacterial diversity.
The researchers say that in addition to highlighting the importance of fruits and vegetables as natural sources of microbiota, their findings also highlight the importance of adopting good agricultural practices.
"The ingestion of plant-associated bacteria through consumption of fruits and vegetables is one of the major links between the human microbiome and the environmental microbiome. Therefore, any factors that influence the native fruit and vegetable microbiota, i.e. farming methods, culture and post-harvest handling, may directly/indirectly affect the composition of the gut microbiota," the researchers said.
Researchers are already embarking on an international study in which people eat the exact same thing for a period of time and then have their feces analyzed. Although this depends on the results of the study, it may also be possible to personalize diets to meet special needs.
Gabriele Berg, another corresponding author of the study, said: "Each fruit and vegetable has a unique microbiome. So maybe at some point, a personalized diet can be tailored to that."
The research was published in the journal Gut Microbes.