When I first saw the NPR FreshAir headline, “Eating Yogurt Is Not Enough: Rebalancing The Ecosystem Of 'The Microbes Within Us’” my first response was, “Of course it is not enough, you need to eat a wide assortment of raw fermented foods and prebiotics!”

Thirty-seven minutes later, Ed Yong, the science writer who recently released his new book, I Contain Multitudes, hadn’t mentioned the vast assortment of fermented foods that humans have enjoyed for thousands of years, but had made clear the fundamental truth that we do not really understand the complex interactions between the foods and microbes we eat, and our health.  In the interview with Terry Gross, Yong talks about some of the most fascinating aspects of microbes and the way they intimately shape our world.  Here are a few of my favorite highlights and my thoughts on those subjects.

• His critique of probiotics was more of the supplemental kind and because we don’t yet understand exactly what different microbes do or how to ensure they stick around.  He seemed confident that most supplemental probiotics tend to pass right through although I don’t think we have enough information to even be sure of that.  I suspect that he’s right when he posits that probiotic supplements tend to be made up of probiotics that are easy to culture and encapsulate over any proven therapeutic criteria.  They don’t cause harm, and I think they can be helpful and I think there is a lot more we could understand about them.
   
• When it comes to the microbes we live with there is really no such thing as ‘good’ or ‘bad’ bacteria, rather it is about our relationship with these microbes. In so many ways our binary way of thinking means we miss the fascinating nuance of our interrelationship with our microscopic cohabitors. Yong reminds us that when the relationships with our microbes are in balance, they act as key partners to help us digest food, boost our immune systems, and protect against disease. It is when the relationship breaks down that microbes can do harm. As above, so below, I suppose. :)
   
• The research behind probiotic pills is ‘underwhelming’ and this is likely because the species being selected for the pills are easy to manufacture and package, not because they are the best at establishing themselves in the gut.  This shouldn’t be shocking when we consider how unchecked capitalism has affected our food system, health care system, and our culture in general - but that’s another blog altogether. Despite this, Yong says the idea behind giving ourselves beneficial probiotics is solid, it’s just not yet clear which ones, or by what method.  I’d like to point out that wild fermented foods like sauerkraut and kimchi have naturally occurring bacteria and have been a part of human nutrition in most of the world for at least as long as we’ve had agriculture.  Intentionally or not, these foods provided a steady trickle of healthy probiotics down the hatches of our ancestors and over time, we’ve probably worked that into our health plan.  Plus they taste good and consist of mostly vegetables, which provide excellent food for you and your microbes.
   
• The conversation about fecal transplants is cool because they are so effective, in spite of the scientific method lagging way behind the practice.  I’m looking forward to a deeper understanding of what is going on, but I’m glad there are doctors who were willing to try it and to understand it later.  I’m skeptical of the scientists who believe they can formulate an imitation fecal transplant.  Like breast milk and so many other things, it seems dicey that humans believe they can improve on something that nature has taken millions of years to cultivate.  Sigh.  Feces seem pretty accessible and the only reason I see to attempt to make a lab based substitute is to make money off of an otherwise free and abundant resource.  That’s not a good reason in my book and probably won’t work as well as the real poop. 
   
• Bacteria have been around a lot longer than us.  If the history of the planet were one year, and the beginning of the planet was January 1st, and today was December 31st 11:59pm - Yong said bacteria have been around since early March and humans have been at the party for about a half an hour!  He also points out that microbes have ruled the planet for most of history, and it turns out, that’s still the case. We are just more habitat for our rulers. Hail to the microbe.

While Yong didn’t prescribe for us all to eat more fermented foods in this interview, like I would have, or mention human species’ historical relationship with probiotic filled tasty fermented foods, my evening plan is still to grab a jar a kraut and curl up with this fascinating book, I Contain Multitudes.