When we think about hormones, we often think about the ovaries, thyroid, or adrenal glands.

When we think about gut health, we think about digestion.

But these systems don’t operate independently.

Your gut is constantly communicating with your brain, immune system, metabolism, and endocrine system. And the trillions of microorganisms living in your digestive tract, the gut microbiome, are active participants in this conversation.

Scientists are increasingly studying what is sometimes called the gut–endocrine axis: the two-way communication between the gut microbiome and our hormones.

One of the most fascinating examples is estrogen.

Meet the Estrobolome

The estrobolome refers to the collection of gut bacteria and bacterial genes involved in estrogen metabolism.

After estrogen is produced, the liver metabolizes it and prepares estrogen compounds for elimination. Many of these compounds are transported through bile into the intestines.

This is where the gut microbiome comes into the picture.

Certain gut bacteria produce an enzyme called β-glucuronidase, which can remove the molecular group attached to estrogen metabolites by the liver. This can make some estrogen compounds available for reabsorption into the bloodstream rather than being eliminated in the stool.

In simplified terms:

Estrogen → liver → digestive tract → gut bacteria → potential estrogen reabsorption or elimination

This is one reason researchers are interested in how the gut microbiome may influence estrogen exposure and metabolism.

And the relationship isn’t limited to estrogen.

What about progesterone?

Research into the gut–progesterone connection is much newer, but it’s fascinating. Gut microorganisms appear capable of interacting with steroid hormones and their metabolites, and researchers are investigating whether microbial metabolism of steroids could influence hormone signaling.

Pregnancy is particularly interesting because progesterone levels rise dramatically while the gut microbiome also undergoes significant changes.

We don’t yet have evidence that changing the microbiome can reliably increase or decrease a woman’s progesterone levels. But the research suggests that the gut may participate in steroid hormone metabolism in ways we are only beginning to understand.

What about cortisol?

The connection between the gut and cortisol is part of the broader gut–brain axis.

Your stress response is regulated in large part by the hypothalamic–pituitary–adrenal (HPA) axis.

Stress can affect the gut, and communication from the gut can also influence the body’s stress response.

Microbial metabolites, immune signaling, and communication between the digestive tract and brain may all play a role.

Research into probiotics and cortisol has produced promising but mixed results, so it would be an oversimplification to say that “bad gut health causes high cortisol.” Instead, the evidence suggests that the gut and stress-response system communicate in both directions.

And the thyroid?

Researchers are also investigating a gut–thyroid axis.

The microbiome may interact with thyroid physiology through immune regulation, intestinal metabolism, microbial metabolites, and potentially aspects of thyroid hormone metabolism.

This is especially interesting in autoimmune thyroid conditions, where researchers have observed differences in gut microbial communities.

But again, correlation doesn’t necessarily mean causation. We don’t yet know whether microbiome changes contribute to thyroid disease, result from thyroid disease, or both.

The takeaway isn’t that your gut controls your hormones.

It’s that your gut is one part of a much larger biological network that communicates with your endocrine system.

So what can you actually do to support that network?

5 Ways to Support Your Gut–Hormone Connection

1. Eat a Diverse, Fiber-Rich Diet

If you want to support your microbiome, start by feeding it.

Your gut bacteria thrive on many of the fibers and plant compounds found in whole foods. Different microorganisms utilize different types of nutrients, which is why diversity matters.

Aim to regularly include:

• Vegetables of different colors
• Berries and other fruits
• Beans and lentils
• Oats and whole grains
• Nuts and seeds
• Leafy greens
• Cruciferous vegetables
• Herbs and spices

Rather than looking for one magical “gut health food,” think about the overall diversity of your diet.

A wide variety of plant foods provides a wider variety of fibers and other compounds for your microbiome.

And don’t forget fiber.

Fiber supports regular bowel movements and provides fuel for microorganisms that produce beneficial metabolites.

If your current diet is low in fiber, increase it gradually. A sudden increase can cause bloating and gas.

2. Support Regular Elimination

The gut is one of the body’s routes for eliminating metabolized hormones and their byproducts.

That makes regular bowel movements an important, and often overlooked, part of digestive health.

Constipation doesn’t necessarily mean you have “estrogen dominance,” but maintaining healthy bowel function supports the body’s normal elimination processes.

It’s also important to remember that constipation doesn’t always mean going days without a bowel movement. You can have a bowel movement every day and still be constipated if you’re not completely emptying your bowels, have to strain, or frequently feel like you still need to go afterward. This is sometimes referred to as incomplete evacuation and can be an overlooked sign of constipation.

Helpful strategies include:

• Drinking adequate fluids
• Eating fiber-rich foods
• Eating fruits and vegetables
• Adding ground flax or chia if tolerated
• Eating kiwi or prunes
• Walking regularly
• Establishing a consistent bathroom routine

If you’re persistently constipated, don’t simply assume it’s hormonal. Medications, thyroid function, diet, pelvic floor dysfunction, dehydration, and many other factors can contribute.

3. Include Fermented Foods

Fermented foods can add microbial diversity to your diet and are an easy way to incorporate potentially beneficial microorganisms.

Examples include:

• Plain yogurt
• Kefir
• Sauerkraut
• Kimchi
• Miso
• Tempeh

You don’t need to eat huge amounts.

Try incorporating a small serving regularly and pay attention to how your body responds.

And remember: more isn’t always better. Someone with a sensitive digestive system may tolerate certain fermented foods better than others.

4. Manage Stress

This may be one of the most underrated ways to support the gut–hormone connection.

Your gut and brain are in constant communication through the nervous system, immune system, hormones, and microbial metabolites.

When you’re chronically stressed, your HPA axis is activated more frequently, influencing cortisol and other aspects of the stress response.

At the same time, stress can affect digestion, gut motility, appetite, and the intestinal environment.

This doesn’t mean you need to eliminate stress from your life, which isn’t realistic.

Instead, create regular opportunities for your nervous system to shift out of “go mode.”

Try:

• Walking outside
• Deep breathing
• Meditation
• Yoga
• Journaling
• Spending time with people you enjoy
• Taking short breaks during the workday
• Creating a consistent bedtime routine

Stress management isn’t just about feeling calmer.

Your gut and nervous system are listening to each other.

5. Move Your Body

Movement benefits far more than your waistline.

Regular physical activity supports metabolic health, cardiovascular health, mood, sleep, muscle, and bone health—and it may also influence the composition and function of the gut microbiome.

For women, movement becomes especially important during perimenopause and menopause.

As estrogen changes, maintaining muscle and bone becomes increasingly important. Resistance training and weight-bearing activity can be particularly valuable during this stage of life.

And movement doesn’t have to mean an intense workout.

Think:

Walk. Lift. Stretch. Play. Garden. Dance. Move throughout the day.

Consistency matters more than perfection.

The Bigger Picture

The emerging research on the gut–endocrine connection is fascinating because it challenges the idea that each body system operates independently.

Your gut communicates with your:

Estrogen system → through the estrobolome and estrogen metabolism

Stress system → through the gut–brain and HPA axes

Thyroid system → through immune regulation, metabolism, and microbial interactions

Steroid hormones such as progesterone → through emerging pathways of microbial steroid metabolism

But this doesn’t mean that every hormonal symptom is caused by your gut.

It doesn’t mean that probiotics can “balance your hormones.”

And it certainly doesn’t mean that you need an expensive supplement or “hormone detox.”

The research is still evolving.

What we can say with much greater confidence is that supporting overall gut health is one piece of supporting overall health, and healthy lifestyle habits benefit many of the same systems involved in hormonal regulation.

So instead of trying to manipulate one hormone or one bacterial species, focus on the bigger picture:

Feed your microbiome.
Support regular elimination.
Include fermented foods if you tolerate them.
Manage stress.
Move your body.

Your hormones and your gut aren’t separate conversations.

They’re part of the same conversation happening throughout your body.