Hormonal changes during perimenopause don’t just affect your periods—they influence how every cell, tissue, and system in your body functions. In fact, perimenopause can be a major trigger for the onset or exacerbation of autoimmune conditions. In this blog post, we’re diving into the fascinating connection between your hormones, your gut, and your immune system—and most importantly, what you can do to support your body through it.
The Hormonal Shifts of Perimenopause
The two major hormonal changes that define perimenopause are:
- A decline in progesterone, due to less regular or less robust ovulation.
- Erratic fluctuations in oestrogen, often higher than before, before starting a more steady decline later on.
These hormonal shifts don’t just impact your reproductive system—they interact with receptors throughout the entire body, influencing mood, metabolism, immune regulation, and gut function.
Autoimmunity and the “Triad”
According to Dr. Alessio Fasano, a leading researcher in this field, three key ingredients are needed for an autoimmune condition to develop:
- A genetic predisposition
- Increased intestinal permeability (aka “leaky gut”)
- A trigger—such as stress, infection, environmental toxins, or hormonal shifts like those experienced during perimenopause
Let’s take a closer look at the last two components of this triad.
Leaky Gut and Immune Dysregulation
Your intestinal lining plays a critical role in your immune system. It forms a selective barrier that allows nutrients in while keeping harmful substances out. When this barrier becomes compromised—a condition often referred to as “leaky gut”—larger particles such as undigested food, bacteria, and toxins can pass into the bloodstream and trigger an immune response.
This process contributes to systemic inflammation and, in susceptible individuals, can pave the way for autoimmune conditions.
Key causes of leaky gut include:
- Diets high in refined carbs, sugar, and ultra-processed foods
- Chronic stress
- Alcohol
- Gut dysbiosis (imbalanced gut bacteria)
- Certain medications (e.g. NSAIDs, antibiotics)
- Eating too frequently without rest periods
- Gluten
Even without digestive symptoms, leaky gut can manifest as fatigue, brain fog, joint pain, or skin issues—because the inflammation it triggers is systemic.
Common Autoimmune Triggers
Even if you have a genetic predisposition, autoimmunity usually doesn’t happen without a trigger. Common ones include:
- Chronic stress: Disrupts immune regulation and keeps the body in a prolonged state of inflammation.
- Hormonal shifts: Particularly fluctuations in oestrogen, which plays a key role in immune modulation.
- Infections: Both viral (like Epstein-Barr virus) and bacterial (like Helicobacter pylori or Lyme-related pathogens).
- Environmental toxins: Heavy metals, pesticides, air pollution, and other modern exposures that challenge the immune system.
When these triggers are layered on top of a compromised gut barrier, the immune system may start to misfire—mistaking your own tissues for invaders.
The 5R Gut Healing Approach
In functional medicine, a popular framework for healing the gut is the “5R” approach. Here’s how it works:
1. Reset
Shift your lifestyle to support digestive health—slow down meals, chew thoroughly, avoid eating when stressed, prioritise sleep, and manage stress.
2. Replace + Support
Support digestion by replenishing what might be missing—like stomach acid, bile, or digestive enzymes. You may also benefit from probiotics.
3. Remove
Identify and remove inflammatory foods such as gluten, refined carbs, alcohol, caffeine, and ultra-processed foods. Address any infections or overgrowths through targeted support.
4. Rebalance
Rebuild a healthy gut microbiome through a diet rich in prebiotic fibres, fermented foods, and a diversity of plant-based foods.
5. Repair
Support the healing of the gut lining using key nutrients such as:
- Vitamin D3 (test and supplement accordingly)
- Vitamin A (retinol form)
- L-glutamine, zinc carnosine, NAG, DGL, aloe vera, slippery elm
- Omega-3s (EPA and DHA)
- Bone broth or collagen
Nutritional Foundations for Gut and Immune Health
Here are some foods to regularly include:
- Protein: Grass-fed meats, oily fish, organic poultry, free-range eggs, quality (unflavoured) protein powders
- Veg: Half your plate in non-starchy, colourful vegetables and herbs
- Berries: Blueberries, raspberries, cranberries, strawberries
- Starchy carbs: Sweet potatoes, squash, beetroot, carrots, quinoa, brown rice
- Healthy fats: Avocados, nuts, seeds, olive oil, flaxseed, coconut, grass-fed butter
- Fermented foods: Sauerkraut, kefir, kimchi, live yoghurt, fermented pickles
- Prebiotics: Onions, garlic, leeks, asparagus, Jerusalem artichokes
- Resistant starches: Cooled potatoes or rice, green bananas, inulin, raw potato starch
- Vitamin A-rich foods: Organ meats like chicken liver
Lifestyle Tips to Support Digestion
- Eat slowly and mindfully
- Avoid eating on the go
- Take 3–5 deep breaths before meals
- Chew each bite thoroughly (30–40 times)
- Stick to 3 meals a day with 4-hour gaps
- Fast overnight for 12 hours (e.g. 7pm–7am)
Final Thoughts
If you’re dealing with strange new symptoms, or autoimmune conditions that seem to have appeared or worsened during perimenopause, you’re not imagining things. The gut-immune-hormone connection is very real.
The empowering news is—there’s a lot you can do to support your body. Starting with gut health is one of the most powerful first steps.
Need personalised support? I offer both a 3 month one to one Nutritional Therapy package and a supportive monthly membership to help you navigate perimenopause with clarity and confidence. Book a free discovery call so we can meet online and figure out the best option for you and if we are a good fit 🙂
Prefer to listen? Listen to the full podcast episode: Autoimmunity & Perimenopause: Triggers, Gut Health, and What You Can Do
