She came to me frustrated.
Not the dramatic, at-her-wit’s-end frustrated. The quieter kind, the kind that comes from doing the right things for a long time and still not feeling the way you expected to feel.
She was bloated most afternoons, even on days when she’d eaten well. Her mood felt unpredictable, not low exactly, just uneven. She’d noticed a kind of brain fog that descended most mornings and lifted, if she was lucky, by mid-afternoon. And despite training consistently and eating enough protein, her body composition wasn’t shifting the way it should.
When I asked about her digestion, the bloating, the irregularity, the way her stomach felt unpredictable from one day to the next, she paused.
“I just assumed all of that was normal at my age,” she said.
It is common. It is not normal. And it is not something you simply have to accept.
The symptoms she was describing, the bloating, the mood instability, the brain fog, the stubborn weight, are all connected to a system most women have never been properly introduced to. Not because it’s obscure or complicated, but because the research is relatively recent, and mainstream health conversations have been slow to catch up.
Your gut microbiome. And its profound, measurable relationship with your hormones.
What Your Gut Microbiome Actually Is
Your gut microbiome is the vast community of microorganisms, bacteria, fungi, viruses, and other microbes that live primarily in your large intestine. There are approximately 38 trillion microbial cells in the human body, outnumbering human cells at roughly a one-to-one ratio. This community is so metabolically active, so influential on virtually every system in the body, that researchers have begun referring to it as an organ in its own right.
A healthy, diverse microbiome performs functions that are essential to your wellbeing: it produces short-chain fatty acids that fuel the gut lining and reduce inflammation; it synthesizes vitamins including B12, K2, and folate; it trains and regulates the immune system (approximately 70 percent of your immune tissue lives in your gut); it produces neurotransmitters including serotonin (around 90 percent of the body’s serotonin is made in the gut); and it plays a direct role in how your body processes and recycles hormones, including oestrogen.
The Estrobolome: The Gut-Hormone Connection You Need To Know About
Within your microbiome lives a specific collection of bacteria called the estrobolome. These bacteria produce an enzyme called beta-glucuronidase, which is responsible for deconjugating, essentially reactivatin, oestrogen that has been processed by the liver and sent to the gut for excretion.
When the estrobolome is healthy and in balance, this process is well-regulated: some oestrogen is reactivated and recirculated, while the rest is excreted. When the estrobolome is disrupted through antibiotic use, poor diet, chronic stress, alcohol, or insufficient dietary fibre, this balance breaks down.
An overgrowth of beta-glucuronidase-producing bacteria can cause too much oestrogen to be reactivated and recirculated, contributing to oestrogen dominance, associated with heavy periods, breast tenderness, mood instability, and weight gain. Conversely, an impoverished estrobolome can result in insufficient oestrogen recirculation, accelerating the symptoms of oestrogen decline in perimenopause.
Research published in the journal Maturitas found that the composition of the gut microbiome changes significantly across the menopause transition, and that these changes are associated with shifts in oestrogen metabolism, body composition, and inflammatory markers. In other words: what is happening in your gut is directly influencing your hormonal experience of perimenopause and postmenopause.
How Stress Disrupts Your Gut (And Why Last Week’s Article Meets Here)
The gut and the brain are in constant bidirectional communication via the vagus nerve, a pathway so significant it has its own name: the gut-brain axis.
When cortisol is chronically elevated, as we covered last week, the gut is one of the first systems to feel the effects. Chronic stress reduces gut motility, increases intestinal permeability (what is sometimes called “leaky gut”), reduces microbial diversity, and shifts the composition of the microbiome toward less favourable bacterial populations.
This creates a self-reinforcing loop: stress disrupts the gut, a disrupted gut produces less serotonin and more inflammatory signals, those signals travel via the vagus nerve back to the brain and amplify the stress response. Anxiety, low mood, and heightened cortisol reactivity are not just psychological experiences, they have a microbial dimension.
A landmark review published in Nature Reviews Neuroscience described the gut microbiome as a key regulator of the stress response, with significant implications for mood, anxiety, and cognitive function. For women in midlife navigating the compounding effects of hormonal change and life demands, the state of the gut microbiome is not a peripheral concern. It is central.
Signs Your Gut Microbiome May Need Support
- Bloating, particularly after meals that don’t seem to warrant it
- Unpredictable bowel habits, constipation, loose stools, or alternating between the two
- Brain fog that lifts later in the day or after eating certain foods
- Mood instability, anxiety, or low mood that doesn’t have a clear external cause
- Skin issues including adult acne, eczema, or rosacea (the gut-skin axis is well established)
- Frequent colds or slow recovery from illness
- Sugar and carbohydrate cravings that feel disproportionate to your actual hunger
- A sense that certain foods ‘don’t agree with you’ that wasn’t there in your 30s
What Actually Supports A Healthy Gut After 40
Diversity of plant foods
The single most well-supported dietary intervention for gut health is variety. Research from the American Gut Project found that people who ate 30 or more different plant foods per week had significantly more diverse microbiomes than those who ate 10 or fewer. This does not mean eating 30 servings, it means 30 different types: vegetables, fruits, legumes, wholegrains, nuts, seeds, herbs, and spices all count.
Each plant food feeds different bacterial populations. Diversity in, diversity out.
Prebiotic fibre
Prebiotics are the specific types of fibre that feed beneficial gut bacteria. Particularly good sources include garlic, onion, leek, asparagus, Jerusalem artichoke, green banana, oats, and chicory root. These foods feed the bacterial populations that produce short-chain fatty acids, the compounds that reduce gut inflammation, support the gut lining, and improve insulin sensitivity.
Fermented foods
Fermented foods introduce live beneficial bacteria directly into the gut. A landmark Stanford study published in Cell found that a high-fermented food diet increased microbiome diversity and reduced markers of inflammation more effectively than a high-fibre diet alone. Useful sources include plain Greek yoghurt, kefir, sauerkraut, kimchi, miso, tempeh, and as those of you who made the Portobello Beef Burger a few weeks ago will know, fermented condiments like the BBQ sauce in that recipe.
Even small, consistent amounts of fermented food appear to have meaningful effects on microbiome composition over time.
Manage cortisol – consistently
As the gut-brain axis makes clear, no amount of dietary intervention fully compensates for a nervous system under chronic load. The practices at the heart of the Strong Calm Lean Method, yoga, pranayama, meditation, and walks in nature, are gut health interventions as much as they are stress interventions. The two cannot be meaningfully separated.
Minimise microbiome disruptors
Alcohol, ultra-processed foods, and artificial sweeteners have all been shown to reduce microbial diversity and disrupt the gut lining. This does not mean perfection is required, but consistent, daily exposure to these compounds has a cumulative effect on the microbiome that dietary fibre alone cannot offset.
The Strong Calm Lean Perspective
Your gut health affects your oestrogen metabolism. Your oestrogen levels affect your cortisol sensitivity. Your cortisol affects your sleep. Your sleep affects your muscle recovery. Your muscle mass affects your metabolism, your insulin sensitivity, and your hormonal environment.
These are not separate topics. They are one interconnected system. And the Strong Calm Lean Method works at all of them simultaneously, because addressing one in isolation, while ignoring the others, is why so many women do the right things and still don’t feel the way they deserve to feel.
Your gut is not a footnote to your health. It is the foundation of it.
If the symptoms in today’s article sound familiar the bloating, the brain fog, the mood shifts, the weight that won’t move, I’d love to hear what’s happening in your unique physiology.
Book a complimentary Roadmap Call and let’s talk. I’ll listen to what’s going on for you, and if I feel I can help, I’ll share the options to work with me inside the Strong Calm Lean Method. It’s a no-pressure conversation, and you’ll walk away with clarity and value either way.
Book Your Free Roadmap Call: www.karmabeing.com