Collection of microbes in the gastrointestinal tract changes with the diet we eat

Microbes are all around us; in the air we breathe and surfaces we touch. But, we don’t fall sick from exposure to microbes. Why? Because our bodies possess an immune system capable of defending against harmful microbes when we are healthy. More importantly, many of the microbes we are exposed to are harmless, and maybe even beneficial to our metabolism.


Specifically, microbes find their way into our gut (during birth and from the food we eat) and colonized the mucous membrane, and thereafter, work together with the host cells to aid in digestion of food through the secretion of enzymes that break down complex biomolecules in food into simpler ones suitable for absorption into the body. Present not alone but as a consortium of different species with different metabolic characteristics, these microbes are collectively known as a microbiome and its community structure (i.e., types and relative abundance of microbes present) has been correlated with significant implications on host health and diseases such as metabolic syndrome and obesity. In particular, deviation of the gut microbiome from a healthy consortium comprising a variety of Proteobacteria and Firmicutes as well as other species, known as dysbiosis, have been shown in a variety of research studies to lead to disease states of the gut as well as disturbance in host metabolism.


In a recent article in the New York Times (Link, with a cute cartoon that shows the concept of how diet affects the gut microbiome and, in turn, host nutrition and metabolic state), diet’s effect on gut microbiome community structure and dynamics have been reported where subjects eating a typical high calorie American diet have less diversity of microbial species compared to others on a calorie restricted diet (1800 calories per day) with low fat and carbohydrates. For example, subjects on a low calorie diet comprising substantial amount of fruits, vegetables and nuts intake have a significantly different gut microbiota compared to those on a high calorie diet, with the noted presence of many beneficial species. This corroborated earlier studies which link changes in diet to corresponding changes in the variety and relative abundance of different microbial species in the gut.


Thus, changing the microbial diversity and composition and, by extension, metabolic profile of the gastrointestinal tract, may ultimately hinge on the type of food we eat. Hence, nutrition and dietary science may hold a significant lever in the global fight against obesity and the lead on disease of metabolic syndrome and diabetes, that have inflicted and continue to impact on substantial numbers of the global population.


Category: microbiome, biochemistry, microbiology,

Tags: gut microbiota, microbes, dysbiosis, community structure, microbial ecology, diversity, metabolic syndrome,


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s