Fish Oil May Protect Against Weight Gain

Fish Oil May Protect Against Weight Gain

Gut microbes found responsible for the metabolic benefits of a fish oil-diet

Fish oil seems to be everywhere in the news recently — and rightfully so. Fish oil has been shown to promote a proper inflammatory response, ease joint soreness, protect the heart and contribute to mental acuity, among other benefits.

But new research now reveals a benefit of fish oil that seems to have even caught even the scientists conducting the research off-guard.

Scientists set out to establish whether gut microbes directly contribute to the metabolic differences associated with diets rich in healthy fats (e.g., fish oil) and unhealthy fats (e.g., bacon) with the goal of identifying interventions for optimizing metabolic health in humans.

The lab study conducted at the University of Gothenburg and reported in the journal Cell Metabolism shows mice that received transplants of gut microbes associated with a fish oil diet were protected against diet-induced weight gain and inflammation compared with mice transplanted with gut microbes associated with a lard diet.

Researchers didn’t expect fish oil to change the gut microbiome community into a powerful weight loss and anti-inflammatory treatment.

In another set of experiments in the study, scientists conducted “fecal transplants” to test whether fish oil-diet microbes could improve the health of mice fed only lard and vice versa. The results provide additional evidence that gut microbe communities can both determine and recover health problems caused by poor diet.

“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 per se had such large effects on health,” said study author Robert Caesar.

The study demonstrates that gut microbes are an independent factor aggravating inflammation associated with diet-induced obesity and gives hope that a probiotic (such as fish oil) might help counteract a “greasy” diet.

“However, further investigations will be needed to determine if this bacteria can be used as probiotic strain and, in that case, how it should be combined with diet to optimize health outcomes” according to study authors.


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