New research shows that our DNA may have more control over our gut microbiome than we thought.
Here’s an experiment best tried with friends who are also part of a group of health-conscious individuals (your yoga class, a meditation retreat, a kombucha tasting). Pose this question: Will you please raise your hand if you’ve ever entertained the idea of fecal transplant therapy?
Depending on how self-savvy your friends are, we’re willing to bet that the majority of hands go up. Yep, there are now large subsets of our culture that are considering swapping defecant in the name of better health.
In this new age of gut-microbiome awareness, many of us are acutely aware of how bacteria in our gut affect our overall health...and we are willing to put a lot of crazy things into our bodies try to try to make our microbiome flourish. New research has added another layer of complexity to our gut-flora puzzle by sharing how our own DNA has a profound effect on the microbiome.
Researchers out of Harvard and Brigham and Women’s Hospital studied the feces of mice and found a subclass of our DNA, microRNA, that actually controls the growth of bacteria in our stomach. They also discovered that this microRNA is designed to work with specific types of bacteria: in other words, it acts as a lock-and-key system to promote related bacteria. The study was published in Cell Host and Microbe this week.
Admittedly the study was done on mice, so we can’t directly apply it to the human gut. However, scientists also found at least 17 types of microRNA in the mice that are also present in human. Unlocking the microRNA-gut-bacteria connection is a particularly exciting development in understanding the microbiome because of its medical applications. Dina Fine Maron of Scientific American explored the research and gave this account of how it may translate into medicine:
Previously, much of the focus on microbiome health benefits has focused on the medical applications of fecal transplants—taking one person’s feces and placing them inside another’s colon in the hopes of recalibrating the bacteria in the recipient’s gut. But the prospect of tapping different microRNAs to modulate different specific bacteria could be a very appealing alternative. Theoretically, it could be simpler and more targeted to use gene blueprints from sequencing data to build something that mimics microRNAs—binding to the same things the microRNA would—than embarking on a fecal transplant and ensuring it is safe.
It is easy to get caught up in worrying that our microbiome is an unchanging force that has control over our bodies and minds. We’re seeing that this is not the case. The importance of the gut-brain connection has been reported in Wellness Warrior, but now researchers have surmised that the relationship may go both ways (i.e. our thinking, our moods, may affect our microbiome). We’ve also learned about the importance of exercise in gut microbial diversity, further corroborating our understanding that our actions and our choices can change our gut health, which in turn can change our overall health. The microRNA research is yet another example of how our bodies are influencing these microbes and not the other way around.
Our understanding of how we interact with bacteria is constantly evolving. For instance, research last week showed that our estimate of the ratio of bacterial cells to human cells, previously thought to be 10:1 may be off by a whole decimal and really more like 1:1. We have so much more to learn and this is still a very new field of biological research, so if the thought of a fecal transplant horrifies you, there still may be hope for your gut after all.
PHOTO: via the Human Microbiome Project
- Scientists bust myth that our bodies have more bacteria than human cells via Nature
- Does our Microbiome Control Us or Do We Control It? via Scientific American
Read all stories by Damon Cory-Watson