The finding out about bacteria and the consumption of different fats comes from a study using mice. Experiments revealed that mice fed a diet rich in fish oil had a different gut microbial composition (microbiome) to those fed a diet rich in lard. The gut bacteria are different and this leads to different metabolic effects. These metabolic effects were measured in terms of weight-gain and inflammation, both of which are associated with obesity and diabetes.
With the mice, the rodents were divided into two groups. One group was fed a fish-oil rich diet and another group fed a lard rich diet, mostly based on bacon. The feeding regime continued for 11 weeks. The quantities of lard and fish oil had the same number of calories and the same quantities of dietary fiber.
Examinations revealed the mice on the lard-rich diet had high populations of Bilophila bacteria whereas those on the fish oil rich diet had high populations of a bacterium called Akkermansia muciniphila. A. muciniphila is a relatively newly identified bacterium, being first reported in 2004. A. muciniphila is able to use mucin as an energy source. Mucin is a type of human intestinal tissue. There is considerable research underway to see the extent that A. muciniphila is associated with weight loss. Here the view, as Nature reports, is that consuming the bacterium could increase the gut wall thickness, with the addition of mucin, which will block food from being absorbed by the body.
The beneficial effects were also demonstrated by transferring bacteria isolated from the intestines of mice fed the fish-oil rich diet to guts of other mice. In turn, harmful effects were observed when bacteria from mice fed a diet rich in lard were transferred into other mice. Transfer was a form of fecal transplant, the type being trialed on people to deal with antibiotic resistant pathogen infections.
It was observed that mice with the fish-oil associated bacteria were protected against diet-induced weight gain and inflammation. This effect was not observed with mice transplanted with intestinal bacteria associated with a lard diet
The inference from the study is that the composition of gut bacteria affects some of the health benefits derived from diets high in fish oils and they also affect some of the less beneficial effects from eating a diet rich in other types of fat.
It should be noted that the study, so far, relates to mice and the same physiological effects may or may not be seen with people. Nonetheless, the study adds to other published works showing how the composition of bacteria in the human body, especially the gut, interacts with overall health and wellbeing.
The research was conducted at the University of Gothenburg. The findings are published in the journal Cell Metabolism. The research paper is titled “Crosstalk between Gut Microbiota and Dietary Lipids Aggravates WAT Inflammation through TLR Signaling.”
