THIS CONTENT IS BROUGHT TO YOU BY NTNU Norwegian University of Science and Technology - read more
Study: Your body weight affects your gut microbiota
Your body weight and genes influence the types of bacteria you have in your gut. This, in turn, likely affects your risk of developing conditions such as coeliac disease and haemorrhoids.
Gut bacteria. You have trillions of them. They affect digestion and how your body absorbs nutriens.
At the same time, they play a key role in your immune system, so it is important to take good care of them.
A new study now shows that body weight also affects gut microbiota.
“We demonstrate that there is a correlation between gut microbiota and body weight. We have also observed that having a high BMI is detrimental to gut microbiota,” says Professor Kristian Hveem.
Body weight therefore causes direct and adverse changes in the gut microbiome, which in turn can lead to disease. This is also influenced by your genes.
12,662 Norwegians participated
Hveem previously headed the K.G. Jebsen Center for Genetic Epidemiology at NTNU.
He also helped establish the HUNT Biobank and led it for 20 years. This biobank stores and contributes to new analyses of material from the large HUNT Study in Trøndelag, in which over 250,000 people have contributed health data.
During HUNT4, he led the collection of stool samples from more than 13,000 participants. Researchers performed detailed mapping of both bacteria and viruses in the gut of 12,662 of these participants.
They also examined how people’s genes influence the composition of their gut microbiota.
In total, the researchers used data from 28,000 people in various parts of the study.
Linked to coeliac disease and haemorrhoids
These bacteria, along with fungi, viruses, and other microorganisms, constitute what is known as the gut microbiome. It is important to maintain a healthy gut microbiome.
“Research shows that gut microbiota may also be linked to conditions such as coeliac disease and haemorrhoids,” says Hveem.
Although the researchers have demonstrated a correlation betweenthe gut microbiome and various diseases, the underlying cause has yet to be determined.
Interaction between genes, body weight, and disease
Your gut microbiota alone do not determine whether you get sick or not. The picture is much more complex than that.
“There is also an interaction between genetics, the composition of the gut microbiota, and the risk of disease,” says Hveem.
Your genes also influence the types of bacteria in your digestive system. With this study, the researchers have taken an important step forwards.
Linking specific genes to bacteria and their functions
“We can link specific genes to specific bacterial species found in an individual, and not just which genes and bacteria, but also what these bacteria do,” says Hveem.
This is an important step that could prove useful for future research.
Reference:
Marta Riise Moksnes, Kristian Hveem mfl.: The HUNT study identifies host genetic factors reproducibly associated with human gut microbiota composition. Nature Genetics, 2026. DOI: 10.1038/s41588-026-02502-4
———
Read the Norwegian version of this article at forskning.no
More content from NTNU:
-
When some people buy better health, others pay the price
-
Why some people are more bothered by low-frequency sounds
-
A horse can benefit both the patient and the therapist
-
How Ukrainian soldiers are trained to become mentally resilient
-
Football: How to become technically skilled
-
New findings about the evolution of the brain: "I was blown away. My first reaction was, is this real?
