Have you ever heard of the 'human gut microbiota' - the community of good and bad bacteria residing in your intestines? I personally haven't until about two years ago when I became actively interested in this area of biological sciences. 

People usually know this as the 'gut flora', but I assume 'microbiota' is a more representative term. 

The bulk of knowledge and data in this field has only grown recently, due to the advent of cheaper and faster sequencing and imaging technologies. 

To educate myself about the microbiota and its implications with health and diseases, I attended/watched various lectures, I read scientific studies and I also read books from researchers in the field.

One of these books, [_Missing Microbes_](https://www.amazon.com/gp/product/0805098100/), was written by Dr. Martin J. Blaser, Professor of Translational Medicine and Microbiology, and the Director of the NYU Human Microbiome Program. I consider Dr. Blaser one of the leading researchers in this field. To learn more about him see [his page at NYU](http://www.med.nyu.edu/medicine/labs/blaserlab/v1-mbr_blaser.html).

<center>https://s15.postimg.org/ua9zkbpaz/What_I_Learned_from_Missing_Microbes_by_Martin_B.jpg</center>

In this post I'm going to share a few of my highlights from the book and I will make commentaries whenever appropriate.
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## My Notes from Missing Microbes by Martin Blaser

First of all, I need to provide some context for what the book is about. 

The book was written for the general public, but the moderate load of medical terminology would make me think otherwise. 

The scope of the book is to explore the alteration/degradation of the human internal microbial ecosystem (microbiota) as a result of modern lifestyle and inconsiderate medical practices. 

### 1. Life on Earth was for the most part of its timeline: microbial.

_"We live on a microbial planet that is totally dominated by forms of life too small to be seen by the naked eye. For about 3 billion years, bacteria were the sole living inhabitants on Earth."_ [1]

- humans and hominid species are latecomers. Here's an example from Dr. Blaser so that you can get a good scale of the matter: 

_" If 3.7 billion years of life on Earth were compressed into a twenty-four-hour clock, our hominid ancestors would have appeared 47–96 seconds before midnight. Our species, Homo sapiens, arrived on the scene 2 seconds before midnight."_ [1]

- as we emerged as a species a few million years ago, we have learned to co-evolve and cohabitate with microbes. They are all over and inside us: mouth, nose, ears, skin, and gut. 

### 2. We come to life with a clean 'microbial' slate.

- we acquire most of our microbes as we pass through the birth canal - we bathe in a pool of lactobacilli (a microbial group dominant in the vaginal microbiota):

_"Whether the birth is fast or slow, the formerly germ-free baby soon comes into contact with the lactobacilli in the vagina. Very flexible, rather like a glove, the vagina covers the newborn’s every surface, hugging its soft skin as it passes through. And with that hugging a transfer occurs. The baby’s skin is a sponge, taking up the vaginal microbes rubbing against it. The baby’s head faces down and is turned toward the mother’s back to fit snugly in the birth canal. The first fluids the baby sucks in contain mom’s microbes, including some fecal matter. Labor is not an antiseptic process, but it has been going on like this for a long time — at least 70 million years since our earliest mammalian ancestors."_ [1]

- throughout life we acquire more microbial diversity, as we are exposed to different environmental and lifestyle conditions (think diet for example). Diversity seems to be beneficial:

_"Loss of diversity leads to disease or to collapse of the system when keystone species—ones that exert a disproportionately large effect on the environment relative to their abundance—are lost."_ [1]

### 3. We have more microbial than human cells.

- it was initially estimated that we have about 30 trillion human cells and 100 trillion microbial cells
- more recent (2016) estimates get this ratio closer to 1, but still in favor of microbes

_"Microbes go from zero to trillions in a short time. There is a well-choreographed succession from the founders to the later inhabitants over the first three years of life."_ [1]

### 4. Bacteria in the colon help with getting the biggest bang for the 'nutritional' buck. 

_"The microbes in your colon break down fibers and digest starch. In one sense, everything that has passed through to the end of your small intestine is on its way out, indigestible by you. But those hungry bacteria in your colon can metabolize quite a lot. They can digest the fibers in an apple that has passed through your small intestine and turn them into food—primarily to feed themselves—but some of their products, especially molecules called short-chain fatty acids, are released and actually feed you, starting with the cells in the wall of your colon. They nourish you, their innkeeper."_ [1]

- in light of this, it makes sense consuming a diet that provides nourishment to the microbes. - I currently think that optimizing a diet is more a matter of focusing on micronutrients, plant matter, and phytochemicals than on macros (carbs, fats, protein). 

### 5. One of the most important functions provided to us by microbes is immunity. 

_"First, there is innate immunity, based on the fact that most of the microbes with which we are in contact have structural patterns that are “seen” by proteins and cells that guard our surfaces. Then adaptive immunity is based on the recognition of highly specific chemical structures. And microbial immunity is based on the microbes that are already in your body, your long-term residents, inhibiting outsiders through various mechanisms."_ [1]

- immunity as well as the interaction of the gut and the brain (the gut-brain-axis) is one of my greatest research interests! 

### 6. Poor gut microbiota content diversity is disease promoting

- asthma, food allergies, hay fever, eczema, and other similar conditions resemble immune dysfunction:

_"Food allergies are everywhere. A generation ago, peanut allergies were extremely rare. Now, if you stroll through any preschool, you will see walls plastered with “nut-free zone” bulletins. More and more children suffer immune responses to proteins in foods, not just in nuts but in milk, eggs, soy, fish, fruits—you name it, someone is allergic to it. Celiac disease, an allergy to gluten, the main protein in wheat flour, is rampant. Ten percent of children suffer from hay fever."_ [1]

- conditions like Chron's disease, IBD, and ulcerative colitis develop in the context of poor gut function. 

### 7. We harm our gut flora in multiple ways

- we made our world too clean => can lead to poor gut microbiota diversity
- we overuse/abuse antibiotics (they are good, but not for every condition):

<center>https://s18.postimg.org/gmgyfbk15/What_I_Learned_from_Missing_Microbes_by_Martin_B.jpg</center>

_"Diagram showing the difference between non-resistant bacteria and drug resistant bacteria. Non-resistant bacteria multiply, and upon drug treatment, the bacteria die. Drug resistant bacteria multiply as well, but upon drug treatment, the bacteria continue to spread."_ [[source](https://commons.wikimedia.org/wiki/File:WhatIsDrugResistance.gif)]

Dr. Martin Blaser says:

_"I worry that with the overuse of antibiotics as well as some other now-common practices, such as Cesarian sections, we have entered a danger zone, a no-man’s-land between the world of our ancient microbiome and an uncharted modern world."_ [1]

- we consume foods that do not feed the gut (highly processed and packaged foods)
- pass me some dirt, will you?!

_"A lot of parents these days try to ramp up their kids’ immune systems by exposing them to pets, farm animals, and barnyards or better still by allowing them to eat dirt."_ [1]

### 8. Antibiotics have been/are of tremendous help to humanity. Abusing them may lead to opposite effects

_"Formerly lethal diseases like meningitis, heart valve infection, and childbirth fever could be cured. Chronic bone infections, abscesses, and scarlet fever could be prevented and cured. Tuberculosis could be arrested and cured. Sexually transmitted diseases like syphilis and gonorrhea could be cured. Even my case of paratyphoid could be cured without months of illness and a big risk of dying. Cure also was a great form of prevention, since a cured person would not spread the pathogen to others. Surgery got safer. Antibiotics could be given pre-operatively to lower the risk of many surgical infections. If infection developed, antibiotics came to the rescue."_ [1]

- doctors need to be better prepared to distinguish among conditions caused by bacteria and viruses:

_"An astute clinician knows that in most, but not all, cases, children who are at risk for developing serious complications show certain warning signs. They have higher fevers, their symptoms have been going on longer, their white blood counts are more abnormal, and they look worse. But many cases fall into a gray area. This gray area is important. Until doctors can readily distinguish viral from bacterial throat infections, they will always follow the safer course."_ [1]

### 9. There is no big pharma conspiracy (imho); at least not in the terms that's been thought of.

_"It is not profitable for companies to go to the trouble and enormous expense of developing new antibiotics, especially if they don’t have broad application. Pharmaceutical companies want to develop drugs that millions of people will take for years, such as medications to treat high cholesterol, diabetes, and high blood pressure."_ [1]

- pharmaceutical companies are for profit; it makes sense for them to develop their strategies in a direction to increase such profits. 
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## Ending thoughts 

I realize that this is already 1,500 words long so it may become unreadable. I only covered about one tenth of the notes and highlights I got from the book, so, I may continue this in future posts. 

I'll end by leaving you with a recent (Sept. 6, 2016) lecture given by Dr. Martin at The American Society for Microbiology:

<center><iframe width="560" height="315" src="https://www.youtube.com/embed/KwK_O0ahDKo" frameborder="0" allowfullscreen></iframe></center>
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### <center>To stay in touch with me, follow @cristi</center>

Citations from:

**[[1. Martin Blaser - Missing Microbes](https://www.amazon.com/gp/product/0805098100/)]**

Credits for Images: [[Martin Blaser via Amazon](https://www.amazon.com/gp/product/0805098100/)] and [[By NIAID - NIH, Public Domain, via Wikimedia Commons](https://commons.wikimedia.org/wiki/File:WhatIsDrugResistance.gif)].

#science #research #books
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[Cristi Vlad](http://cristivlad.com), Self-Experimenter and Author