Why Autoimmunity Often Starts in the Gut (And What You Can Do About It)
When we talk about autoimmune conditions, most people think about the immune system attacking the body — the thyroid, joints, skin, or nervous system.
But what many don’t realise is this:
For a large number of people, the process often begins in the gut.
The Autoimmune Association highlights “The gut plays a central role in immune system regulation, and disruptions in gut health may contribute to autoimmune disease.”
Not overnight.
Not from one single trigger.
But from a slow breakdown in how the gut and immune system communicate.
Your Gut Is Your Immune System’s Training Ground
Around 70–80% of your immune system lives in your gut.
It’s constantly making decisions:
What is safe
What is harmful
What needs to be attacked
What should be tolerated
When your gut is healthy, this system is well-regulated.
But when the gut becomes irritated or inflamed, that regulation can start to break down.
What Starts to Go Wrong
There are a few key things I commonly see in clinic:
1. Gut Lining Breakdown (“Leaky Gut”)
Your gut lining is designed to be selective — letting nutrients through while keeping larger particles out.
When it becomes compromised:
Food particles
Bacteria
Toxins
can pass into the bloodstream.
Your immune system sees these as threats and mounts a response.
Over time, this can increase overall immune activation.
2. Ongoing Inflammation
Things like:
Chronic stress
Poor diet
Alcohol
Infections
Certain medications
can all contribute to inflammation in the gut.
This keeps the immune system in a heightened, reactive state.
3. Microbiome Imbalances
Your gut bacteria play a huge role in regulating immunity.
When there’s imbalance (dysbiosis), it can:
Increase inflammation
Reduce immune tolerance
Impact how your body responds to triggers
4. Immune Confusion
Here’s where it becomes more significant.
As the immune system is repeatedly activated, it can begin to lose its ability to clearly distinguish between “self” and “non-self.”
In some cases, this may contribute to the development or worsening of autoimmune conditions.
Why This Matters for Thyroid and Hormones
This is especially relevant if you’re dealing with:
Hashimoto’s
Graves’ Disease
Thyroid symptoms
Perimenopause changes
Unexplained fatigue, bloating, or skin issues
Because the gut, immune system, thyroid, and hormones are all deeply connected.
If the gut is under stress, it can:
Drive inflammation
Disrupt thyroid signalling
Worsen hormonal symptoms
Make recovery feel harder than it should
What You Can Focus On Instead
The goal isn’t to “fix everything at once.”
It’s to reduce the load on the immune system and support the gut to function properly again.
Some simple starting points:
Support the gut lining
Prioritise whole, nutrient-dense foods
Include protein regularly
Consider gut-healing nutrients where appropriate
Reduce inflammatory load
Identify foods that may be triggering symptoms
Look at stress levels and nervous system support
Support regular bowel movements
The Bigger Picture
Autoimmunity is rarely caused by one single thing.
It’s usually a combination of:
Genetics
Environment
Stress
Gut health
Immune regulation
Toxic load
But the gut is often one of the most powerful places to start.
Because when you support the gut, you’re not just working on digestion —
you’re helping to calm, regulate, and guide the immune system back into balance.
If This Sounds Like You
If you’ve been dealing with ongoing symptoms and feel like your body is reacting to everything…
There’s usually a reason.
And more importantly — there’s a way to work through it.
Natasha Gedrim (BHSc Naturopathy)
Thyroid and Hormone Naturopath
