A new study has found that after just a few days of eating a high-fat diet, the gut’s defenses are broken down, and an asymptomatic inflammation is triggered that can develop into a long-term problem. Importantly, the effects were reversible.
Ahh, fast food. We know it’s not good for us, but we still eat it because it’s quick and affordable – not to mention tasty. There’s no need to trot out all the research linking a diet high in fat, which typifies fast food, to poor health; that information is well known. But one thing that fast food does that isn't as widely known is contribute to inflammation.
New research, led by Australia’s Walter and Eliza Hall Institute of Medical Research (WEHI), has again confirmed this finding. It found that eating just a few meals of fast food can trigger silent inflammation that slowly breaks down our gut defenses, and sets us up for chronic inflammation.
“We’ve shown that every meal we consume actively shapes our gut health,” said the study’s corresponding author, Dr Cyril Seillet. “The more saturated fats we eat, the more inflammation that builds up – gradually weakening our gut defenses and increasing our susceptibility to chronic inflammation. But this inflammation build-up is initially silent, remaining hidden in our bodies until years later, where it can present as chronic inflammation.”
To investigate the physiological and molecular impact of short-term exposure to a high-fat diet, the researchers fed mice with either that kind of diet or a regular diet for seven days. They found that in mice fed a high-fat diet, the physiological function of the gut was altered within a week. A decrease in key proteins led to a loss of gut integrity. The researchers also showed, for the first time, that short-term exposure to a high-fat diet reduced production of interleukin-22, or IL-22, a protein involved in regulating inflammation, tissue repair, and the defense of the gut’s protective layer, the mucosal barrier.
“IL-22 is a critically important protein for gut health and protection,” said lead author, PhD student Le Xiong. “Without it, the gut loses its ability to prevent inflammation. It took only two days of consuming high-fat foods for the mice to lose their IL-22 stores and have an impaired gut function. Despite their gut protection capabilities being stripped away, the mice still looked healthy – highlighting how gut health can be compromised long before any visible symptoms appear.”
While saturated fats reduced IL-22 production in the mice, the researchers found that unsaturated fats, such as those found in nuts and avocados, did the opposite. They believe that effect would be seen in humans and want to direct future research toward exploring ways to naturally boost IL-22 levels.
The study was published in the journal Immunity.
Source: WEHI
