Seemingly Unrelated Symptoms That Might Point to Gut Issues
Connecting the dots to uncover overlooked issues.
You’ve probably heard the phrase that "everything starts in the gut."
It’s become cliché in the world of functional medicine and biohacking, but it’s rooted in some truth.
The gut isn't just about digestion and bowel movements. It's the control center for multiple systems in the body.
You’ve probably also at some point heard about the gut-brain axis. It refers to the two-way communication channel that links your enteric nervous system (the gut’s own neural network) with the central nervous system.
Through the vagus nerve, endocrine and immune pathways, the gut is constantly sending and receiving signals to your brain.
But there’s also the gut-skin axis, where specific microbes in your gut and the overall composition of your microbiome can trigger inflammatory responses that show up as issues like acne, eczema, rosacea and psoriasis.
The gut-liver axis, the gut-thyroid connection and the gut-hormone feedback loops all play roles too.
When your gut is off, the effects can spread throughout your entire body.
Your gut is in many ways ground zero for systemic health.
Why Gut Issues Often Go Unnoticed
Not all gut dysfunction announces itself.
Sure, many of them come with things like bloating, gas, diarrhea or pain that is pretty noticeable.
But there’s a lot that can go wrong in the gut without any obvious signs.
And since symptoms often appear in other areas of health due to the gut’s far-reaching impacts, many people’s digestive problems go undetected or get misdiagnosed.
If dealing with cognitive issues, most people’s first thought probably isn’t about their gut. The same with skin issues, anxiety and a long list of other symptoms that can be directly tied to the gut.
In most cases, we have to start with a zoomed out view and consider all possibilities before narrowing in the focus on specifics.
Seemingly Unrelated Symptoms Tied to the Gut
Let’s run through some common symptoms that may actually be rooted in the gut.
This list isn’t exhaustive, but it highlights what I’ve seen most often and also further shows how widespread issues in the gut can be.
Brain Fog, Anxiety & Depression
The gut produces around 90% of your serotonin, contains over 500 million and is in constant communication with your brain.
It’s called the second brain for a reason. Here’s several issues in the gut that can cause disrupt cognition:
Dysbiosis impacting production of neurotransmitters like serotonin, dopamine and GABA
Pathogen overgrowth producing toxic metabolites (like D-lactate) that disrupt cognition
Leaky gut allowing toxins like LPS to cross the blood-brain barrier, driving neuroinflammation
Chronic Fatigue
There are many direct and indirect ways that the gut can impact energy levels. Some of the most common being:
Malabsorption of B vitamins, iron, magnesium due to issues like overgrowth, inflammation or deficiencies in enzymes or stomach acid
Low SCFA production, reducing mitochondrial energy and increasing inflammation
Dysbiosis-triggered systemic inflammation draining your energy
Frequent Headaches & Migraines
Issues in the gut are rarely suspected when it comes to this. But it can be the result of:
Microbiome shifts involving decreased diversity or low anti-inflammatory microbes like Faecalibacterium
Overgrowth of histamine-producing microbes causing histamine-induced migraines
Intestinal permeability allowing inflammatory molecules into circulation
Sleep Disruptions
This is usually a two-way street with gut issues disrupting sleep but also poor sleep disrupting the gut.
Issues in the gut that can be disrupting sleep:
Dysbiosis and inflammation disrupting tryptophan metabolism and reducing serotonin production, both of which disrupt melatonin synthesis (~400x more melatonin is produced in the gut than the pineal gland)
Reduced GABA production by beneficial gut bacteria
Dysbiosis and inflammation suppressing circadian clock gene expression and disrupting cortisol levels
Low Libido & Hormonal Imbalance
This is a far more common cause of hormone disruptions than most people realize. It commonly involves:
Poor estrogen detox due to dysbiosis or low bacterial β-glucuronidase function
High cortisol from gut-driven inflammation suppressing sex hormones
Nutrient deficiencies (like zinc, vitamin D, B6) due to disrupted digestion or motility
Chronic systemic inflammation from issues like leaky gut shifting resources away from hormone production and disrupting receptor signaling
Skin Issues (Acne, Eczema, Rosacea)
Your skin is usually a pretty good indicator of where things stand in your gut.
Problems with the skin can be a sign of:
LPS in the bloodstream (a marker of leaky gut) triggering systemic skin inflammation
Overgrowth of pathogens driving inflammation
Disrupted digestion or motility leading to deficiencies in important nutrients for skin health (like zinc or vitamins A, C E)
Become a Detective
Health issues don’t usually show up with a blinking arrow pointing to the root cause. More often, they’re a tangled web of symptoms.
This is why you have to think like a detective.
Look at the bigger picture. If you’re experiencing many different symptoms, even symptoms that don’t seem connected at all, consider how they might be.
The first signs of gut dysfunction aren’t always digestive.
They might be something seemingly unrelated, like reduced libido, trouble focusing or always being tired.
A perfect example of this is someone I worked with who came to me with psoriasis. No gut complaints at all. But after running some testing, we found a very inflamed colon, and overgrowth of several opportunistic bacteria.
Once we addressed the gut, the skin began to clear.
This is where testing becomes powerful. Your surface symptoms might be obvious, but what’s driving them might not be. Without testing, and without analyzing the timing, triggers and context of your symptoms, you might be treating the wrong thing altogether.
Most situations require investigation.
If you don’t have time to do that yourself or you've tried without success, I offer 1:1 consultations where we do that deep work together.
I’ll help you uncover what’s actually driving your symptoms and map out a clear path forward.
Click here for more info.