SINGAPORE – Scientists have found a protein in the gut that acts like a “middleman”, connecting your lunch, your gut bacteria and your liver health.

By examining stool samples, the team, led by Nanyang Technological University, found that people with higher levels of this protein tend to develop fatty liver disease later in life.

The study, headed by Andrew Tan, an associate professor and vice-dean of innovation and enterprise at the Lee Kong Chian School of Medicine (LKCMedicine), focused on angiopoietin-like 4, a protein found in the gut that can cause a leaky gut, a condition in which the gut becomes overly porous.

This allows bacteria from the gut to travel directly to the liver, where they can trigger inflammation and the build-up of fat.

The researchers used not only preclinical models but also human data collected from three patient cohorts from Singapore, Thailand, China and India. The whole exercise took between three and four years and provided the team with a window into how diet can affect the liver, Tan said.

“We know what we eat changes the bacteria in the gut, so we intentionally picked these three countries that are very different in their dietary intakes... and, hopefully, similar to that of Singapore. We took faecal samples from patients in the different disease states to measure the protein levels. It turned out to be a very good marker for gut health, unlike blood markers,” he said.

LKCMedicine doctorate student Damien Chua said doctors used to think fatty liver primarily affects the liver itself, “but actually the damage starts early on in the gut”.

“They tend to use serous markers from blood samples, but we found from our cohort studies that these do not actually align properly, so they were not as robust as we thought they were. With our biomarkers from faecal samples, we are also able to look at a different aspect of what constitutes a leaky gut,” said Chua, who is also the principal investigator of the research.

“In this regard, our research has not only changed the...