Getting a gut feeling: serotonin and your gut bacteria
When it comes to the microbiome (that’s the collection of microscopic bacteria, fungi, viruses and more that live on your skin and in your gut!), the science is evolving all of the time. Scientists have only really been able to study it in the last two decades, so we’re still learning all the time about how it works and affects the body’s other processes.
But one thing’s for sure – our microbiomes make a big difference in how we look and feel, from causing acne to producing serotonin.
At Dermala, we’ve spent a lot of time studying how the gut and skin microbiomes can cause or prevent blemishes and other skin issues, but we’re also very interested in the other emerging fields around the microbiome. (After all, our founder and head honcho is a microbiologist!)
So, we thought it’d be interesting to examine the ways that scientists now believe gut bacteria affects the body’s serotonin and the brain overall.
But first, what is serotonin?
If we want to talk about serotonin and the gut, we should probably talk about what serotonin is first!
Serotonin, a.k.a. 5-hydroxytryptamine (5-HT), is a neurotransmitter that also acts as a hormone. It affects mood, digestion, sleep, bone health, and your body’s ability to clot blood as part of wound healing. It’s super important! And, as you might guess, too much or too little serotonin can negatively affect you, both physically and emotionally.
Serotonin is especially known, along with dopamine, for its affects on a person’s mood. These are considered mood boosters, the happiness hormones, and in their absence, people are more likely to experience anxiety and depression. When people feel down, they’re often advised to get more sunlight and exercise – both of which boost serotonin production.
So, what does serotonin have to do with the gut?
You may be surprised to learn that the gut provides approximately 95% of the body’s serotonin! While a lot of this goes into plasma (for things like blood clotting), it’s not isolated from the body’s other functions.
As we mentioned briefly above, the gut microbiome is the collection of microorganisms gathered in your gut – mainly in your large intestine. The whole thing weighs about 4.4 lbs (can you believe?) and is now believed to be an integral part of how our bodies work and communicate with our brains.
Some scientists studying the link between our gut microbiomes and minds have even come up with a new term for the aspects of the microbiome that affect mood and behavior – the “psychobiome.” Fun, right?
Here’s how scientists think the gut-brain connection works
There are actually several ways that microorganisms in the gut can have a wider effect on the body’s systems, as far as we know right now.
- The microbes in your gut can secrete various substances that enter the bloodstream through blood vessels, giving them a ride straight to your brain and throughout your system.
- The microbes can prompt or stimulate the cells in your gut to behave certain ways. For example, they can cause neuropod cells to stimulate the vagus nerve (which connects directly to the brain!) or stimulate enteroendocrine cells which then send hormones out into the body.
- Microbes can cause inflammation and affect your body’s immune cells, indirectly affecting all sorts of things throughout the body, from your mind and ability to focus to your skin. Inflammation in the gut is frequently a problem for people with stubborn acne that doesn’t respond to regular treatments!
This may all sound a little freaky and sci-fi, but if you think about it, people have always believed their gut affected things. After all, you get a gut instinct, right? We’ve long said that you get butterflies or the feeling of a pit in your stomach.
Now we just know a little more about the science behind the feelings!
Does that mean I can change my mood with bacteria?
Well, maybe! The science around the gut microbiome and its applications is very much still developing. There’s no magic mood pill right now, but there are microbiologists working on finding out how serotonin production in the gut works, how it affects our minds and bodies, and how we might be able to apply new knowledge about the microbiome to help predict, prevent, or treat a wide variety of conditions, from anxiety to constipation. (In the meantime, you can definitely try to add more microbiome-friendly foods to your diet!)
Right now, we know that people whose guts are lacking in Coprococcus bacteria are more likely to have depression or IBS (though it’s hard to say yet whether that’s correlation or causation). We know that in mice, scientists were able to isolate specific bacteria that changed the mouse’s ability to digest (for the better!). And of course we know that inflammation stemming from an out-of-whack microbiome can having wide ranging effects, including on the skin.
In short? Gut bacteria have a lot to do with serotonin in the body
It’s an exciting time to be a microbiologist! Keep an eye out for new therapies and supplements packed with pre- and probiotics – it’s the next frontier in medicine for the body and mind.