Even just a few high-fat meals can quickly weaken the gut’s natural defenses, triggering inflammation long before any visible symptoms appear, a Melbourne-based medical institute revealed on Monday.
In pre-clinical trials, researchers discovered that just two days of consuming foods high in saturated fats significantly reduced levels of IL-22, a key protective protein that maintains gut health and helps control inflammation, said a study by the Walter and Eliza Hall Institute (WEHI), Australia’s oldest medical research institute.
Despite appearing healthy, test mice showed microscopic signs of inflammation and impaired gut function, according to the study published in the Journal of Immunity.
“Every meal we consume actively shapes our gut health,” said WEHI’s Cyril Seillet, senior author of the study.
“The more saturated fats we eat, the more inflammation that builds up, gradually weakening our gut defenses and increasing our susceptibility to chronic inflammation,” said Seillet.
Chronic inflammatory conditions, such as coeliac disease, inflammatory bowel disease, and rheumatoid arthritis, affect roughly one in three Australians. However, how these diseases develop has remained poorly understood, researchers said.
This study showed that high-fat diets not only spark inflammation but also suppress the body’s ability to fight it by depleting IL-22. Encouragingly, researchers also found that unsaturated fats, like those in nuts, seeds, and avocados, had the opposite effect, boosting IL-22 and strengthening gut defenses.
“The gut’s protective abilities can be compromised in just two days, even without any outward signs,” said lead author Le Xiong from WEHI.
The team was also able to restore gut function in mice by replenishing IL-22, hinting at the potential of restoring gut health in humans, said the study conducted in collaboration with Monash University, the Baker Institute, and the University of Melbourne.
Researchers hope their findings influence dietary guidelines to focus on naturally supporting gut health through nutrition, particularly by encouraging unsaturated fats and reducing saturated fat intake.
