Why Most Hormonal Issues Start in the Gut!

by Julie Smullen FNC, CGP, CGC

Something has gone wrong in how we think about hormones.....

We’ve been taught to treat them like isolated problems. Low energy? Must be thyroid. Weight gain? Must be insulin.

Mood issues? Must be serotonin.

So, we chase the hormone.

But what if the hormone isn’t the root issue?

What if it’s the environment those hormones depend on?

Because hormones don’t operate in isolation. They respond to signals.

And one of the most powerful signalling systems in the body is your gut.

Your Gut Is Not Just Digestive. It’s Hormonal.

Your gut is a highly active endocrine organ.

Lining your digestive tract are specialised cells that constantly produce and release chemical

messengers that influence:

• Hunger and satiety

• Blood sugar regulation

• Mood and emotional state

• Sleep cycles

• Digestive processes

Around 90% of serotonin is produced in the gut. Hormones like ghrelin, GLP-1, PYY, and CCK are also produced directly in the gut lining.

This means your gut is not just processing food.

It is actively orchestrating hormonal signals throughout your entire body.

When the Gut Is Off, Hormones Follow

When gut health is compromised (through dysbiosis, inflammation, or poor diet), several things begin to break down:

• Chronic low-grade inflammation increases

• Nutrient absorption becomes impaired

• Blood sugar regulation becomes unstable

• Detoxification pathways slow down

• Hormone signalling becomes disrupted

At the same time, the gut’s own hormone production becomes dysregulated.

Your genetics can further influence how severe this becomes.

Some people are more prone to inflammation, less efficient at detoxification, or require higher levels of certain nutrients to maintain balance.

This means two people can have similar gut issues…but very different hormonal outcomes.

This creates a cascade effect across the endocrine system.

This is why you can “treat” hormones directly and still feel stuck.

Because the system influencing them hasn’t been addressed.

10 Hormones Strongly Influenced by the Gut

Cortisol (Stress)

Gut inflammation activates the stress response and can dysregulate the HPA axis, leading to chronically elevated or unstable cortisol levels.

Insulin (Blood Sugar)

The gut microbiome plays a key role in insulin sensitivity. Disruption here is strongly linked to insulin resistance and metabolic dysfunction.

Ghrelin (Hunger)

Produced in the gut, ghrelin regulates hunger signals. Dysregulation can lead to increased appetite, cravings, and poor satiety control.

Leptin (Fullness)

Inflammation driven by poor gut health contributes to leptin resistance, where the brain no longer responds appropriately to fullness signals.

Serotonin (Mood)

The majority of serotonin is produced in the gut. Gut inflammation and dysbiosis are linked to reduced serotonin availability and mood disturbances.

Melatonin (Sleep)

Melatonin is synthesised from serotonin. When gut health affects serotonin production, sleep quality often declines.

Estrogen (Hormonal Balance)

The gut microbiome (sometimes referred to as the estrobolome) regulates estrogen metabolism and clearance. Dysbiosis can contribute to estrogen imbalance.

Thyroid Hormones (Metabolism)

Gut health influences the conversion of T4 into active T3, as well as immune activity that can impact thyroid function.

Dopamine (Motivation)

The gut supports the availability of amino acid precursors needed for dopamine production, linking digestion directly to motivation and focus.

Testosterone (Vitality)

Through its effects on inflammation, nutrient absorption, and hormone-binding proteins, gut health indirectly influences testosterone levels.

Why Treating Hormones Alone Often Fails

Most approaches focus on:

• Supplementing hormones

• Blocking symptoms

• Targeting a single pathway

But hormones are downstream.

They reflect what’s happening internally.

If the gut is inflamed, nutrient-deficient, or dysregulated, hormone balance becomes incredibly difficult to restore long-term.

What Actually Moves the Needle?

Real hormonal balance comes from restoring the internal environment:

• Nutrient-dense, whole foods

• Proper digestion and gut integrity

• Stable blood sugar

• Reduced inflammatory inputs

• Quality sleep and circadian rhythm

• Nervous system regulation

• Sunlight, movement, and environment

These are not optional extras. They are the signals your body uses to regulate hormones.

Where Most People Actually Need to Start.

This is where a lot of people get it wrong.

They try to clean up their diet, reduce stress, and take a few supplements…but the gut is still inflamed, damaged, or dysfunctional.

And until that’s properly addressed, hormones rarely stabilise.

For many people dealing with ongoing gut and hormonal issues, a more structured approach is needed.

This is where frameworks like the GAPS Diet can be incredibly effective.

It focuses on:

• Removing foods that irritate the gut

• Rebuilding the gut lining

• Restoring beneficial bacteria

• Supporting digestion and nutrient absorption

It’s not about being extreme.

It’s about giving the body the right conditions to heal.

Because once the gut starts functioning properly again…hormones often begin to regulate naturally.

The Bottom Line

Hormones don’t just “go out of balance.”

They respond to the conditions you create inside your body.

And your gut is one of the most powerful drivers of those conditions.

Some hormones are produced directly in the gut.

Others are regulated, activated, or cleared through it.

Either way, the message is clear:

If your gut is struggling, your hormones will be too.

For those who have already tried multiple approaches and still feel stuck, tools like SmartDNA can help personalise the process further, giving deeper insight into how your body handles hormones, inflammation, and detoxification.

Work With Me

If you’ve been trying to fix your hormones but still feel stuck, it may be time to look deeper.

This is exactly what I help clients do, identify the root cause, rebuild gut function, and restore the environment your hormones depend on.

Work with me: Work With Me | Mysite

Disclaimer

This article is for educational purposes only and is not a substitute for personalised medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional for individual concerns.

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