Diets With High Fat And High Sugar May Cause Gut Inflammation

According to a report by the researchers at Washington University School of Medicine, St. Louis, and Cleveland Clinic, consuming a Western diet negatively impacts the immune system in the stomach in ways that could raise the risk of inflammation and inflammatory bowel disease.

Diets With High Fat And High Sugar May Cause Gut Inflammation

The research in mice and humans found that a high-sugar, high-fat diet damages Paneth cells, which are immune cells in the gut that help control inflammation. As Paneth cells are dysfunctional, the gut immune system becomes too vulnerable to inflammation, placing individuals at risk of inflammatory bowel disease and undermining successful regulation of disease-causing microbes. The results reported in Cell Host & Microbe on May 18th opened up new avenues for controlling gut immunity by restoring natural Paneth cell activity.

According to the lead author Ta-Chiang Liu, MD, PhD, an associate professor of pathology and immunology at Washington University, inflammatory bowel disease has traditionally been a concern mainly in Western nations such as the United States, but it is becoming more widespread globally because more and more people follow Western lifestyles. The study found that consuming a Western-style diet rich in carbs and calories for an extended period of time impairs the role of immune cells in the stomach, potentially promoting inflammatory bowel disease or increasing the risk of intestinal parasites.

Irritable bowel syndrome is characterized by Paneth cell dysfunction. People with Crohn’s disease, an inflammatory bowel disease characterized by stomach pain, diarrhea, anemia, and nausea, for example, also have Paneth cells that have stopped functioning.

Liu and senior author Thaddeus Stappenbeck, MD, Ph.D., chairperson of the Department of Inflammation and Immunity, Cleveland Clinic and former co-director of the Division of Laboratory and Genomic Medicine, Washington University, aimed to explore the cause of Paneth cell dysfunction in humans. They examined a database containing demographic and medical information on 400 individuals, as well as an evaluation of each person’s Paneth cells. The researchers discovered that having a high body mass index (BMI) was correlated with Paneth cells that appeared irregular and unstable under a microscope. People with higher BMI had the worst Paneth cells. The group was open to all stable adults and Crohn’s disease patients.

The researchers tested two strains of mice that are genetically programmed to obesity to better understand this relation. Such mice overeat daily and they have genes that keep them from feeling satisfied even when feeding a normal diet. Surprisingly, the obese mice had Paneth cells that appeared fine to the researchers.

Obesity in humans is often caused by a high-fat, high-sugar diet. As a result, the scientists fed regular mice a diet containing 40% fat or sugar, which is close to a standard Western diet. The mice had become bloated and their Paneth cells had become noticeably irregular after two months on this food.

Obesity, according to Liu, was not the problem. A balanced diet consumed in excess has little effect on Paneth cells. The issue was caused by a high-fat, high-sugar diet.

When the mice were fed a balanced mouse diet for about four weeks, their Paneth cells returned to a normal state. It remains to be seen if people who consume a Western diet regularly will surely increase their gut immunity by switching to a different diet other than the western diet, according to Liu.

Liu and colleagues are also looking at whether fat or sugar is the main cause of Paneth cell dysfunction. They’ve already been looking at ways to enhance gut immunity and restore natural Paneth cell activity by attacking the bile acid and the two immune molecules are known as farnesoid X receptor and type 1 interferon.