Good Saturday. That was a busy week for a limpet like me, and here is a weird anecdote/book review from said week, but it surely did happen to me.
I have just finished listening to a book called Brain Maker by Dr. David Perlmutter
in which he makes a lot of claims about the positive effects the bacteria in your belly can have on your brain, almost so many that your “cure all” alarm starts to go off, except that he has pretty good studies and science backing him up, and he is quick to say when he is speculating.
Now many of us grew up believing that the tryptophan in turkey made you sleepy, only to be grossly disillusioned as adults when told that wasn’t true. But here is a replacement fact, better than the one before. While this is somewhat dense reading, these folks from the Department of Anatomy and Neuroscience, University College Cork, in Ireland, actually explain this complex system very succinctly in the abstract for their 2014 article, “Serotonin, tryptophan metabolism and the brain-gut-microbiome axis.”
The brain-gut axis is a bidirectional communication system between the central nervous system and the gastrointestinal tract. Serotonin functions as a key neurotransmitter at both terminals of this network. Accumulating evidence points to a critical role for the gut microbiome in regulating normal functioning of this axis. In particular, it is becoming clear that the microbial influence on tryptophan metabolism and the serotonergic system may be an important node in such regulation. There is also substantial overlap between behaviours influenced by the gut microbiota and those which rely on intact serotonergic neurotransmission. The developing serotonergic system may be vulnerable to differential microbial colonisation patterns prior to the emergence of a stable adult-like gut microbiota. At the other extreme of life, the decreased diversity and stability of the gut microbiota may dictate serotonin-related health problems in the elderly. The mechanisms underpinning this crosstalk require further elaboration but may be related to the ability of the gut microbiota to control host tryptophan metabolism along the kynurenine pathway, thereby simultaneously reducing the fraction available for serotonin synthesis and increasing the production of neuroactive metabolites. The enzymes of this pathway are immune and stress-responsive, both systems which buttress the brain-gut axis. In addition, there are neural processes in the gastrointestinal tract which can be influenced by local alterations in serotonin concentrations with subsequent relay of signals along the scaffolding of the brain-gut axis to influence CNS neurotransmission. Therapeutic targeting of the gut microbiota might be a viable treatment strategy for serotonin-related brain-gut axis disorders.
And now for the exciting anecdote. I had really been feeling like I was swimming in soup the past week or so. Nothing particularly wrong, just dragging my feet and feeling kind of weepy. So while I am listening to Brain Maker, I realise that I have been on antibiotics quite a few times throughout my life, some fairly intense, and just recently again this fall, and have had my thrilling chronic cyclical vomiting episodes for years. So maybe this applies to me. Now after my last trip to the hospital last summer at the cottage my father-in-law gave me some probiotics that his pharmacist recommended to him, which I will happily buzz market, called Florastor. I had taken a couple but not continued for no particular reason, and had the small jar here in Ottawa. So I started taking them, two twice a day. To say that my mood improved would be a ludicrous understatement. Nothing external changed, but I swear within two days I just felt the tears back away and I cannot imagine what else could have been the cause of such a large swing. My leg has been quite sore, my side has been quite sore, we haven’t suddenly won the lottery and it is tax season. But the angst is low and the change was so noticeable. Now I understand (so to speak) the placebo effect and the power of suggestion, and if that is what happened here, then bring it on! But I can only heartily recommend both the (slightly preachy) book and upping the probiotics in your life. Yoghurt was already on the menu, but there seem to be a lot of key bacteria out there and once displaced they have trouble reestablishing themselves.
Apparently we are host to a large array of bacteria, or perhaps they are hosting us, as it turns out even our mitochondria, once proud bacteria themselves, have their own dna. Treating these creatures well, and feeding them what they desire, seems a very good idea. And interestingly, some of the bad bacteria crave sugars so in an astonishingly sci-fi moment, it is quite possible that it isn’t you doing the craving, you are merely the delivery mechanism, feeding the host in your gut.
So science and anecdote met in my belly it would appear, and put a smile on my face. I am a little stunned, but feeling very pro probiotic.