Microbiota—Our Bossy Hitch-Hikers

The model for a new emoticon?
The model for a new emoticon?

The microbiota wield a lot of influence inside what we fondly like to think of as “our” bodies. There is no end to the havoc they can cause or alleviate. They can even influence our emotions. Imagine if the truth were admitted, and the universal symbol for love became, instead of a heart, a tangle of intestines?

Childhood Obesity News has been reading up on mouse research which, if it turns out to be meaningful in the effort to quell obesity, also indicates that we need to pay better attention to the tiny inhabitants that make up our gut microbiome. They represent at least a hundred bacterial species, and maybe as many as a thousand. In fact, the paper, “Molecular-phylogenetic characterization of microbial community imbalances in human inflammatory bowel diseases,” suggests there may be as many as 36,000 species.  Most of them are commensal, meaning they get a benefit from us and maybe perform some service in return, but at least they do no harm.

Hundreds of trillions of these creatures dwell inside each of us, and they outnumber us severely. Each person contains 100 or 150 times as many microbial genes as human genes. Three or four pounds of microbiota live in the intestinal tract of the person next to you. MedicalNewsToday.com says:

While the jury is still out on whether gut bacteria is directly associated with obesity, it is an area that certainly warrants further investigation.

One of the widely-reported studies originated with Washington University, but of course that is not the only place where the link between obesity and the microbiome is being explored. Other researchers are building on the work already done. For instance, scientists from Cornell University (USA) and King’s College (UK) affirm that a specific group of microbes called Christensenellaceae minuta live more frequently inside of lean people. Not only that, but apparently our own genes decide whether to encourage that species or kick it to the curb. As we have seen, diet is a factor in whether we are able to do so. Fiber good; saturated fats bad.

The Downside of the Microbiome

Once they have been accepted, and established a home inside us, some kinds of intestinal fauna are demanding guests who insist that we do things for their betterment. Scientists have actually described them as manipulative. Like little kids nagging their mothers in the grocery store aisles, the microbiota know what they want and have their ways of getting it.

In many ways, the power of the microbiome is no surprise. We know that a person can visit another geographic area and become violently sick from water that the indigenous people drink every day. Their inner environments have adapted because their interior populations decreed it.

This short animated film, made by Ben Arthur for NPR, describes the microbiome quite entertainingly.

Your responses and feedback are welcome!

Source: “Molecular-phylogenetic characterization of microbial community imbalances in human inflammatory bowel diseases,” PNAS.org, 08/21/07
Source: “The gut microbiome: how does it affect our health?,” MedicalNewsToday, 03/11/15
Image by Cliff


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About Dr. Robert A. Pretlow

Dr. Robert A. Pretlow is a pediatrician and childhood obesity specialist. He has been researching and spreading awareness on the childhood obesity epidemic in the US for more than a decade.
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Dr. Pretlow’s invited presentation at the American Society of Animal Science 2020 Conference
What’s Causing Obesity in Companion Animals and What Can We Do About It

Dr. Pretlow’s invited presentation at the World Obesity Federation 2019 Conference:
Food/Eating Addiction and the Displacement Mechanism

Dr. Pretlow’s Multi-Center Clinical Trial Kick-off Speech 2018:
Obesity: Tackling the Root Cause

Dr. Pretlow’s 2017 Workshop on
Treatment of Obesity Using the Addiction Model

Dr. Pretlow’s invited presentation for
TEC and UNC 2016

Dr. Pretlow’s invited presentation at the 2015 Obesity Summit in London, UK.

Dr. Pretlow’s invited keynote at the 2014 European Childhood Obesity Group Congress in Salzburg, Austria.

Dr. Pretlow’s presentation at the 2013 European Congress on Obesity in Liverpool, UK.

Dr. Pretlow’s presentation at the 2011 International Conference on Childhood Obesity in Lisbon, Portugal.

Dr. Pretlow’s presentation at the 2010 Uniting Against Childhood Obesity Conference in Houston, TX.

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