Eating the Fear Away

Fear, unfounded or not, is debilitating. I am gaining a new appreciation for fear with my recent reading of an article in Nature magazine. In this article, I found that my previous thinking of this as a purely psychological problem is probably not 100% accurate. As I will explore, our fear and the neural connections that say “when this happens, this is going to happen” is more associated with our bacteria living in our gut, than some faulty processing of this emotion. Truly a groundbreaking insight, at least in rats, but I think we can say it should apply to humans as well.


Let’s talk about my fear. It is heights. I hate them and I even freak out 5 feet from ledges. To take up indoor rock climbing was my attempt to overcome my fear, and I did that for over 12 months with the thought that if exposed enough, my fear would dissipate. Well, after 12 months, despite all the logical self-talk, “You are tied to a rope with a knot that will not come loose, and there is no way to fall,” I still hung to the wall like a cat being forced into the water. I did not enjoy it. 

Fast forward 3 years: I’m climbing again and I am in love with the sport and have no fear of the same heights that had crippled my brain. Have I become so psychologically sound that this was no longer an issue? No, my wife can attest to this. So, what was it? Well, in this article I am going to discuss what gave me some insight into the shift.

The experiment was genius, except for the part about shocking rats. They took 2 groups of rats, one of which had been treated with antibiotics which impaired the bacteria in their gut, and the other group had normal gut flora. They then rang a bell and shocked them until they got both groups accustomed to hearing a bell and becoming fearful of a shock. Then, in the next phase of the experiment, they rang a bell and there was no shock delivered. The scientists monitored their vitals to see how long it would take their fear response to become “extinct” or when the rats heard a bell, they didn’t poop their cage worrying about getting the bejesus shocked out of them. 

The rats that had received antibiotics never got over the bell triggering a fear response. The rats with normal gut flora/bacteria were able to get over the fear of being shocked and didn’t live in fear of the sound of the bell. This is fascinating if the study just stopped there, but it went further to explain the reason.  

The study showed that the right bacteria in the gut releases metabolites/chemicals that instruct the brain that it is ok to “prune” these brain connections that are causing the fear response. If you have the right bacteria releasing the right chemicals, then you can remove the brain connections of cause and effect, i.e. hearing a bell and thinking you are going to get the hell shocked out of you. This is huge! Our bacteria, when our gut is healthy, helps us get over our fears. Amazing insights. The phrase, “You are what you eat” takes on a whole new meaning and it definitely did for me.  

My research over the last 2 years has shown that fiber is much better for your gut flora than taking selected probiotics (probiotics are helpful, but are limited depending on what each specific bacteria you are taking in the probiotic does–they have very specific functions). I like the fiber approach because it helps all of your bacteria.  

Back to my fear of heights. I have been eating much more salad and fibrous foods over the last 3 years and I think that is why I no longer have the fear of heights I did before. Eating right to help your brain heal is the key lesson here and eating right is lots of fiber in the form of vegetables and fruits. If you need some support with your bacteria besides just diet, try Poly-Prebiotic powder to increase your fiber. Your brain and your bacteria will thank you for it.