Justin and Erica Sonnenburg run The Sonnenburg Lab in the Department of Microbiology and Immunology at Stanford. They wrote a book about the human gut microbiota (gut flora) and I assume their purpose was to popularize this growing field of science.
Here are some of the topics and concepts they detail in the book:
- characteristics of the gut flora:
"One of the marvels of the gut microbiota is how rapidly it adjusts to dietary changes. The bacteria in the gut divide quickly, capable of doubling in number every thirty to forty minutes. Species that thrive on the types of food an individual regularly consumes can become very abundant relatively quickly." [source]
- how animal and human studies reveal aspects of the interaction between our gut and the rest of our physiology and psychology (very important interaction primarily mediated via the gut-brain axis and the vagus nerve):
"Our brain and gut are connected by an extensive network of neurons and a highway of chemicals and hormones that constantly provide feedback about how hungry we are, whether or not we’re experiencing stress, or if we’ve ingested a disease-causing microbe. This information superhighway is called the brain-gut axis and it provides constant updates on the state of affairs at your two ends. " [source]
- the central role of the gut flora on the immune system
- details about fecal transplants and their striking results in pathology - primarily in infections with Clostridium Difficile and Salmonella, but also some interesting studies of weight management
- the microbiota and the aging process
The book is not all research oriented. The Sonnenburgs also discuss and provide practical advice for following a diet with emphasis on a healthy gut flora (focus on micronutrient and fiber intake, and fermentation of foods).
They kindof strive to optimize for the intake of MACs - microbiota accessible carbohydrates - and SCFAs - short chain fatty acids -. Last, but not least, they provide recipes! And I assume some of you might be more interested in this section of the book (their recipes' central point is fiber intake).
Now, to be frank, what I don't like about this book is that the foreword is written by Andrew Weil, a popular figure that's been greatly (and for good reason, imho) criticized by the folks at the Science Based Medicine blog.
This is a big no-no, if you ask me, but I'm not going to bash an entire book just because of this 'uninspired' move on behalf of the Sonnenburgs (they could have ulterior motives of which I am not aware).
That being said, should you decide to read the book, here's its Amazon link:
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Cristi Vlad, Self-Experimenter and Author