Flexigut

How do our surroundings influence our health?

In the simplest terms, health is the total sum of the effect of genes, behaviour, and surroundings. But of course, we cannot just change our genes. Therefore, if we want to avoid getting sick, it is more productive to consider influencing our behaviour and surroundings. Ghent University, the University of Antwerp, KU Leuven, and Hasselt University are pooling their expertise in the first large scale ‘exposome’ research project in Flanders.

Thanks to the decoding of the human genome, scientists gained a better understanding of many diseases, leading to numerous new treatments. However, researchers realised that not all illnesses could be explained on the basis of genetic factors. Our behaviour (for example how often we exercise, what is our diet or our stress level) and environmental factors (such as the pollution, living environment, air quality, climate) also influence our health. We call the totality of these non-genetic factors "exposome", a highly variable and dynamic entity that evolves throughout the entire lifetime of an individual and which, together with our genome, determines whether one becomes sick or stays healthy.

“The genome and exposome are very closely linked to one another,” explains Sarah De Saeger (UGent), nutrition expert and coordinator of the Flemish Exposome Project. “For example, you might be genetically predisposed to develop a certain type of cancer, however it is your exposome that determines whether you will get sick, when, and to what extent. The characterisation of the exposome is therefore maybe even more attractive than the genome in terms of preventative medicine. In particular because, unlike the genome, our exposome is something we can actually influence and change. We can adjust our behaviour and also many environmental factors, and thereby reduce the risk of certain health effects.”

Of course, to do this, one first needs to identify and understand which and to what extent environmental factors have an impact on our health. Thanks to iBOF funding (a new interuniversity source of funding, eds.), researchers from the universities of Ghent, Antwerp, Leuven, and Hasselt will work together in the coming 4 years to map as many as possible of these crucial environmental factors. “We are looking into the big wide world outside our bodies, as well as into the microworld inside us, and we do this in relation to the whole life span, from foetuses to adults. This is a unique approach”, explains De Saeger. “In the past, researchers often investigated one specific chemical substance and its impact on one disease. Now, we are approaching this from three different perspectives: external contaminants, processes in our body, and genetics.”

The link between our surroundings and our health

The aim of the Flemish Exposome project is to collect in the first place new insights into the impact of environmental factors on the development of gut and metabolism related disorders, including diabetes, obesity, metabolic syndrome, food allergies, and gastrointestinal cancers. De Saeger mentions: “The project brings together two cohort studies (scientific studies which follow one group of people over a long period) along with partners who collect additional data on environmental factors. The Limburg Birth Cohort study, run by environmental epidemiologist Tim Nawrot (Hasselt University) follows children starting from birth. The researchers take a sample of blood from the umbilical cord at birth, and also store the placenta. This allows them to determine the extent to which the baby has been exposed, for example, to soot particles from air pollution or environmental contaminants, even before birth. The other cohort study, the Flemish Gut Flora Project, is based at KU Leuven. Here, the research group headed by microbiologist Jeroen Raes is mapping the bacteria that live in our gut (the microbiome). They are also looking for possible links between disturbances to our gut flora and different diseases.

The samples from both cohorts are then analysed in the labs of the other partners. Toxicologist Adrian Covaci (University of Antwerp) is investigating plastic-related pollutants and pesticides which end up in our bodies through ingestion of food and dust or through contact with specific consumer products. Sarah De Saeger focuses on mycotoxins, poisonous substances that are produced by fungi that unintentionally end up in our food. Finally, bio-engineer Lynn Vanhaecke (Ghent University) will use metabolomics to make an all-inclusive ‘metabolic fingerprint’ and observe its relationship with that of the microbiome and pollutants, and to study what impact these substances have on our metabolome, microbiome and DNA.