Fish, Pigs, Mice — and Gut Bacteria?

Diets high in different fats increased different gut bacteria in mice


What if you could reap the health benefits of fish oil without ever having to give up other fats?

A new study from Sweden, that looked at the differences in gut bacteria of mice fed different diets, found that a diet high in fish oil produced one kind of bacteria while a diet high in lard produced a different kind.

These findings raise the possibility of transplanting the gut bacteria from someone whose diet is high in fish oil into someone whose diet is high in lard to protect against weight gain and inflammation.

"We wanted to determine whether gut microbes directly contribute to the metabolic differences associated with diets rich in healthy and unhealthy fats," said lead study author Robert Caesar, PhD, a molecular biologist at the University of Gothenburg in Sweden, in a press release. "Our goal is to identify interventions for optimizing metabolic health in humans."

Dr. Caesar and team fed mice diets high in either fish oil or lard for 11 weeks.

The mice fed lard produced a bacteria called Bilophila, which has been linked to inflammation in the gut.

The mice fed fish oil produced a bacteria called Akkermansia muciniphila (A. muciniphila), which has been linked to weight loss and improved blood sugar metabolism.

Dr. Caesar and team then transplanted the A. munciphila bacteria into the guts of the mice fed lard.

These mice, in turn, experienced less weight gain and gut inflammation.

"We were surprised that the lard and the fish oil diet, despite having the same energy content and the same amount of dietary fiber — which is the primary energy source for the gut bacteria — resulted in fundamentally different gut microbiota communities and that the microbiota had such large effects on health," Dr. Caesar said.

This study was published in the August issue of the journal Cell Metabolism.

The Swedish Research Council, the Swedish Foundation for Strategic Research, the Swedish Diabetes Foundation funded this research.

No conflicts of interest were disclosed.