At this point, we don’t know exactly what characterizes the obese microbiome. However, it could be argued that we don’t really need to establish exactly which phyla and species of microbes that play a key role in obesity. Certainly, having more knowledge about the obese microbiome and the role of specific gut microbes in obesity would help us develop probiotics (beneficial bacteria), prebiotics (food ingredients that boost the growth of beneficial bacteria), synbiotics (combination of prebiotics and probiotics), and other products that can modulate the gut microbiome. However, we already have a lot of the knowledge we need to target and treat the obese microbiome.
Third, we know that hunter-gatherers and some traditional populations that are unaffected by western lifestyle are lean, virtually free from diseases of civilization, and have vastly more diverse microbiomes than westerners (However, more studies in this area is needed) (5,6,7). Archeological data also suggest that the modern cosmopolitan lifestyle leads to a significant change to the human gut microbiome (8).
Just like our human genome was forged in the ancestral natural environment, the human microbiome is probably also healthiest when we live in a way that is somewhat in consistence with the hunter-gatherer human lifestyle. This is supported by studies which show that factors associated with the western lifestyle (e.g., antibiotic use, refined diets, c-sections) have a negative effect on the gut microbiome, while factors associated with the hunter-gatherer and traditional human lifestyle (e.g., diets rich in nutritious whole foods, microbial exposures, no access to antimicrobials) promote a healthy microbiome (4,9,10,11) .
Treating the obese microbiome
As both the obese microbiota and obesity itself largely result from a gene-environment mismatch, reconnecting with the natural human environment is the obvious way to retake our health. This doesn’t mean that we have to abandon all aspects of our modern lifestyle and move into the wild, it simply means that we should consider the impact our lifestyle has on our microbial inhabitants. From a practical perspective, studies have shown that avoiding antibiotics (unless they are absolutely necessary), eating fermented foods, avoiding highly processed foods, eating more fermentable substrates, breastfeeding your child, and performing a natural birth are some of the key things you can do to promote a healthy, lean microbiome (12,13,14,15,16). Also, while we need more studies to say for sure, it’s likely that part of the hereditary component of obesity involves the transfer of microbial DNA from mother to child. This means that taking care of your own microbiome is probably a good idea not just for your own benefit, but also for the sake of your children. In combination with new types of advanced microbiome modulators that target specific disorders, these general lifestyle changes will hopefully be enough to rewild our bodies and retake our health.