Researchers for the first time have found that a high fat “western” diet decreases the efficiency of the immune system to fight infectious disease mainly in the gut. And, also it increases the susceptibility to food-poisoning bugs.
This research, published in journal Microbiome, was conducted by APC Microbiome Ireland scientists based at University College Cork.
The Western diet is spreading through the world. It is characterized by high consumption of saturated fat, red meat, and refined sugars- but little fiber.
Researchers fed the mice with a “westernized” diet that is high in fat and low in fermentable fiber. This diet affected both the immune system and the bacteria resident in the gut, called as the gut microbiota.
Even short-term feeding of the high-fat diet increased the number of ‘goblet cells’ in the gut. These cells are the target for infection by Listeria, as well as causing changes to the microbiota structure and immune system. The high-fat diet also causes increased susceptibility to infections beyond the gut.
Diseases caused by pathogens
A study has revealed the direct effects of dietary fats upon both the gut microbiota and the immune system. Increased human ingestion of a ‘westernized’ diet has been related to the intense rise in disorders like type 2 diabetes and obesity.
Listeria monocytogenes is a human pathogen. It is found in contaminated foods which can cause serious disorders, specifically in pregnant women, the aged and immunocompromised people.
According to the researchers, short-term intake of the high-fat diet also increased levels of Firmicutes bacteria. This bacteria is increased in the gut which is linked to obesity. The dietary effects were also seen outside the gut, with reduced immunity throughout the body, local changes to gastrointestinal cell function and alterations to the gut microbiota which enhanced the progression of Listeria infection.
These findings suggest that an individual’s diet may be an important influencer of resistance to infections through effects on the gut microbiota and immune system.
This has significant inferences for human health, particularly during pregnancy, in old age and in immunocompromised people. It also has more wide-ranging implications for a study on infectious diseases.