Could faecal transplants cure obesity?

A connection has been found between the diversity of bacteria in human poo — known as the human faecal microbiome — and levels of abdominal body fat.

Researchers at King’s College London found that participants with a more diverse community of bacteria in their faeces had generally lower levels of visceral fat. Visceral fat is body fat that is stored in the abdominal cavity near a number of important internal organs and is linked with higher risks of metabolic diseases such as cardiovascular disease and diabetes. This type of fat has not previously been linked with the microbiome in humans.

The research, published in Genome Biology, also provides further evidence of possible genetic influences on obesity, through heritable bacteria found in the faecal microbiome.

The study of 1313 twins from the TwinsUK cohort used data from stool samples provided by participants as part of their annual sampling to extract DNA information about faecal microbes. Researchers compared this to six measures of obesity, including BMI and upper to lower body fat ratios, but found the strongest links with visceral fat.

The study is one of the largest to look at links between the microbiome and obesity and adds to a body of evidence suggesting genetic influences on obesity.

While this research highlights genes that are relevant to the association between the microbiome and visceral fat, further research is needed to understand the specific influence of these genes and how this could be harnessed for potential future treatments and interventions.

“As this was an observational study we cannot say precisely how communities of bacteria in the gut might influence the storage of fat in the body, or whether a different mechanism is involved in weight gain,” said Dr Michelle Beaumont, lead author of the study from the Department of Twin Research and Genetic Epidemiology at King’s.

Senior author Dr Jordana Bell, from the Department of Twin Research and Genetic Epidemiology, said further scientific investigation is needed to understand how precisely our gut microbes can influence human health, and if interventions such as faecal transplants can be beneficial.