Research has shown that the gut microbiota may play a crucial role in obesity, with obese patients showing a reduced microbial diversity (1). Overweight and obesity, particularly abdominal adiposity, increase the risk for type 2 diabetes mellitus and cardiovascular disease (CVD). A recent study now explored whether abdominal adiposity is also associated with the gut microbiota (2). The researchers used visceral fat, subcutaneous fat mass and percentage trunk as measures of abdominal adiposity. Measures of abdominal adiposity were obtained from the TwinsUK cohort, as well as their fecal microbiome profiles. They found several significant association between lower bacterial diversity and the presence of certain bacterial species and adiposity measures. Visceral fat (VFM) associations made up the highest proportion of significant results. With the use of heritability analysis, these so-called adiposity-associated bacteria were then used to study host-microbiota interactions at obesity-associated human candidate genes. Studies have shown that obesity seems to be genetically influenced, but the underlying mechanisms remain to be elucidated. The heritability analysis showed several significant associations of adiposity-associated microbes and host genetic variants. This suggests that the obesity-associated genes might influence the presence of adiposity-associated gut bacteria. In other words, a proportion of the heritability in obesity may be related to heritable gut microbes. Thus, this innovative study does not only show strong associations between gut microbial profiles with measures of abdominal fat, but also that host genetic variants may influence the interaction between the human gut microbiota and obesity and its cardio-metabolic consequences.
1. Turnbaugh PJ, Hamady M, Yatsunenko T, Cantarel BL, Duncan A, Ley RE, et al. A core gut microbiome in obese and lean twins. Nature. 2009;457(7228):480-4.
2. Beaumont M, Goodrich JK, Jackson MA, et al. Heritable components of the human fecal microbiome are associated with visceral fat. Genome Biology , 2016;17(1), 189