June 5, 2016 AT 4:00 pm

Linking Gut Bacteria to Mood


The human microbiome is a big deal. We can have as many as 100 trillion microorganisms living simultaneously in our gut. These gut microbiota outnumber our genes by nearly 150x turning homosapiens into a “superorganism”. What are all these microbes doing? They help us digest by fermenting our food. They also have been shown to produce some powerful neurochemicals that have the ability to communicate with our brains. The neuroreceptors inside our intestines and the vagus nerve are the gateways to the brain.


The big three are neurochemicals that are related to our gut and regulate our mood are the following:

  1. dopamine (~50% produced in our gut) – pleasure
  2. serotonin (most of it is produced in our gut) – relays messages to cells related to mood, sex, appetite, sleep, memory and learning
  3. GABA (gamma-aminobutyric acid) – calming


How can you hack your mood through your gut? It is still the Wild West in terms of neuroscience studies coming out on this topic. My personal choice is to eat a ton of fermented foods. Kombucha, water-kefir, ginger beer, sauerkraut, kimchi and some commercial liquid probiotics that I perpetuate. We will get more into biohacking with fermented foods on future posts. A new term for these microbes which can benefit the brain and our behavior are psychobiotics.


  1. Journal of Neuroscience – Gut Microbes and the Brain
  2. NYT – Can the Bacteria in Your Gut Explain Your Mood?
  3. How Your Gut Affects Your Mood

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  1. Tilman Baumann

    Can I get some background on those fermentation controllers?
    I’m working on a kefir and yogurt temperature controller. But I would love to take advantage of something already existing.

  2. @Tilman Baumann – That is a YATC5 temperature controller. I wrote up this post and happen to be the person who designs and sell those controllers. I was trying to avoid hyping my personal stuff, but since you ask: screwdecaf.cx/yatc.html

    It’s all OSHW…

  3. Tilman Baumann

    Looks pretty good. But is perhaps not quite what I was looking for.
    I would prefer to have a PID. That should be fixable being open source and all.
    But also the board turns out would not quite fit the appliance where I would want to embed it into. With the resulting ratsnest of wires to make it fit, I’m not far off from the breadboard solution I’m working on.

    But still. Great project. Loved to see it.

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