#gut brain axis

[existennialmemes]

Your mental illness is not just in your head. Literally. A lot of it is also in your gut. Some of it may also be in your heart. Again, literally.

And all of this is to say:

People who try to dismiss mental issues as being less real or substantive than other physical issues, have demonstrated a profound ignorance about how our nervous system actually operates

[nourishcolourwellness]

[kosher-salt]

Atp we gotta invent a new type of psychiatry but for the enteric nervous system. That's the bit of you that controls the digestive system - and if you've been keeping up with the gut-brain connection research, you'll know we're finding out quickly that much of what we thought we knew about psychology, neurology, was wrong or so incomplete it may as well have been. Alzheimers? Schizophrenia? Depression, acne, anxiety, maybe even things related to connective tissue issues. Sure, there are genes for these things, but as we are so fond of saying: nature loads the gun, nurture pulls the trigger. Also... how are genes connected to your gut flora? Possibly more than we had been considering. Which is wild, considering those bacteria aren't you but separate lifeforms..... or are they?

As we continue to isolate individual strains and determine which causes what, and continue to improve the public's comfort with emerging therapies (it's not a poop transfer. I mean it can be but that would introduce a whole host of bacteria and not the specific ones, so that isn't how we do it, dw.), we are also discovering how wrong we may have been coming at so much of healthcare.

Hindsight 20/20, it's not terribly surprising, imo. The skin of an adult human is ~1.5-2.0 square meters. It's not much relative to your intestines, with all the villi, which are absolutely coated in bacteria. Poo fact, sorry: a lot of the mass of solid waste is just straight up bacteria, if you didn't know. That's why people who have colectomies but still have some unconnected tract/rectum area still have to clear it out (now you know).

There's a lot of stigma that doesn't help the research, because feces is gross (I'm with you on that). Butt, ultimately, so is the rest of the body. It's definitely something to look into. We're discovering new connections between gut flora and other aspects of health constantly. It doesn't help that food producers are starting to get antsy about folks realizing how much of their diet might be detrimental to health, and on that note I worry about the gap consumers already face for various reasons (finances, time, food aversions, energy, grocery availability) in access to non-harmful sustenance. I want people to have access to their best health. I do hope that as this information becomes more well-known by the public, it helps lower stigma around relevant conditions and body types. I think a lot of people who have struggled with health goals (and even body goals that may or may not have health effects) are going to find out it wasn't their "fault."

[bpod-bpod]

Sleepyhead

Doctors often prescribe 'plenty of rest' to help us recover from infections, but even for workaholics, sleep may be unavoidable. Here researchers peering inside a fruit fly (Drosophila) find signs of chemical signals (highlighted in pink) sent between the gut (middle) and brain (left). Chemical cytokines travel through its circulatory system, activating glial cells around the brain. This gut-brain communication can keep the fly awake, but, in times of stress, increasing cytokine signals promotes sleep. While the fly (with its internal structures highlighted in green and blue) takes a long-overdue nap, researchers are looking for similar communication in a genetically similar organism: humans. So, the next time you have a stomach infection, don’t ignore the doctor’s advice to rest – they’re just going with your gut.

Written by John Ankers

Image from work by Alina Malita and colleagues

Department of Biology, University of Copenhagen, Copenhagen, Denmark

Image originally published with a Creative Commons Attribution 4.0 International (CC BY 4.0)

Published in eLife, September 2025

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[hawkeyedflame]

Hey, so I saw that you said that you studied the gut-brain axis, so I’m going to fangirl for a second lmao. Sadly, we only touched up on it briefly in my microbio class (it was taught by an environmental microbiologist, so she only went in-depth about like. dirt), which is a shame because it’s so fascinating. What in particular did you focus on?

(I know I could just look for papers on my own, but I’d rather ask someone who is actually in the field to get an idea of what’s good and what isn’t beforehand)

I focused mostly on biodiversity and the incidence of inflammatory bowel disease and autism, but we studied a range of other illnesses as well, including depression, anxiety, Parkinson's, lupus, asthma, and some others. Fecal matter transplants play a pretty heavy role in the study of novel treatments.

I also worked on a PhD student's study that was searching for a possible connection between GABA-producing bacteria in the gut and the occurrence of depression and anxiety. The results ended up being published in Nature, if I recall correctly.

I'm mainly interested in autism though, personally. The research we have so far implicating gut dysbiosis and poor integrity of the gut lumen in the development and persistence of autism is honestly overwhelming. I would like to get more involved in studying treatment options, because what we have right now shows promise, but isn't comprehensive enough.

[neurosciencenews]

Scientists explore links between genetics, gut microbiome and memory Researchers have honed in on a link between genetics, the gut microbiome, and memory. A new study identified a lactate as a key memory-boosting molecular messenger in mouse models. Mice fed Lactobacillus microbes had increased levels of GABA in their brains.

[bpod-bpod]

Gut Feelings

“Trust your gut” goes the advice, but the 'second brain' in our intestines is already guiding us through life. Researchers believe chemical messages passed through the gut-brain axis affect our mental health, shaping our thoughts and behaviours. They may also hold clues to brain disorders. Here an advanced form of electron tomography virtually strips back layers of tissue in a mouse’s intestine to highlight one of several gland-like crypts in green. Crypts usually produced chemicals needed for gut health, but its pattern of cells (yellow and blue) is different to healthy crypts. This mouse suffers from symptoms similar to Alzheimer’s disease, perhaps revealing links between a malfunctioning ‘dysbiotic’ gut and neurodegeneration. Spotting similar signs in our similar tissues may lead to early diagnosis and more effective management of human Alzheimer’s disease.

Written by John Ankers

Video from work by Francesca Palermo and colleagues

Institute of Nanotechnology – CNR, Rome, Italy

Video contributed by the authors under a Creative Commons Attribution 4.0 International (CC BY 4.0) licence

Published in Science Advances, January 2025

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[bpod-bpod]

Supply and Demand

From stomach twinges in stressful situations to increased hunger at the thought of food, we all intuitively feel the close connection between the brain and the digestive system. Neurons innervating the gut, known as the enteric nervous system, control gut behaviour and enable communication with the brain, especially important for adapting our appetite and nutritional intake to our energetic needs. During reproduction, females of many species need more resources, and research in fruit flies (Drosophila melanogaster) shows how the gut responds to these higher demands. In female flies, hormonal changes after mating affect enteric neurons, causing them to increase release of a small protein, myosuppressin, which relaxes gut muscles; this enables the flies’ stomach-like crop (pictured, with neurons in red) to expand more, helping them to acquire food faster. Comparatively simple, the fly system is a useful first step towards understanding how the digestive system adapts during reproduction and pregnancy.

Read more about this research from the MRC LMS here

Written by Emmanuelle Briolat

Image from work by Dafni Hadjieconomou and colleagues

Gut Signalling and Metabolism Group, MRC London Institute of Medical Sciences, London, UK

Image copyright held by the original authors

Research published in Nature, October 2020

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