Gut Health, Inflammation, and RA & Sjögren’s: What Does the Evidence Say?
- Cristina Montoya, RD
- 4 days ago
- 8 min read
Updated: 18 hours ago
By Cristina Montoya, RD — Arthritis Dietitian
Originally published: November 2019
Updated: March 2026, to reflect the emerging evidence on gut health, inflammation and inflammatory arthritis.
There is no single “autoimmune diet” proven to treat rheumatoid arthritis or Sjögren’s disease. However, research shows that gut health, dietary patterns, and fibre intake can influence inflammation, immune regulation, and quality of life.
Inside this article:
Why a "one-size-fits-all" autoimmune or anti-inflammatory diet doesn't exist
The gut microbiome and autoimmune rheumatic diseases
How the Western diet affects gut health and inflammation in autoimmune disease
Does the Mediterranean Diet reduce inflammation?
Does the Autoimmune Protocol (AIP) diet reduce inflammation?
Fibre, inulin, and methotrexate response in Rheumatoid Arthritis
How to increase fibre safely in rheumatoid arthritis and Sjögren’s disease
How to apply gut–immune nutrition gently without another restrictive diet
Why a "one-size-fits-all" autoimmune or anti-inflammatory diet doesn't exist
If you live with rheumatoid arthritis (RA), Sjögren’s disease (SjD) or another autoimmune rheumatic disease, you’ve probably been told that you should just "change your diet" to control inflammation or even cure your disease.
And yet, the more you try to follow online nutrition advice, the more confusing, restrictive, and stressful eating becomes.
One day, it’s gluten-free.
The next one is dairy-free.
Then, it’s keto, carnivore, AIP, low-lectin, or sugar-free.
No wonder so many people living with autoimmune rheumatic diseases feel anxious, defeated and frustrated with their food choices.
Here is the truth: there is no single “autoimmune” or “anti-inflammatory” diet.
But there is strong, growing evidence that diet quality and gut health can influence arthritis management by modulating the immune system, reducing inflammation, alleviating fatigue, improving pain, and enhancing quality of life.
In fact, long before we had the words gut microbiome, dysbiosis, or immune modulation, clinicians were already noticing a link between digestion and inflammatory arthritis.
A 100-year-old gut health and arthritis insight we ignored
The idea that diet can manage inflammatory arthritis is not new.
In the early 1900s, physicians treating rheumatoid arthritis noted a link between gastrointestinal disturbances and inflammation.
They focused on modifying what they called "intestinal toxemia," which we now recognize as dysbiosis (an imbalance in the composition and function of the gut microbiome) and immune activation.
The recommendations focused on:
Gentle, soft, and easily digestible foods
Fermented milk products
Rest before and after meals
Calm, pleasant mealtime environments
Even a pint of whisky
It has taken more than a century to appreciate this core concept: Gut health and inflammation are deeply connected.
What early clinicians observed intuitively is now being confirmed by modern research:
The gut is much more than a digestive tract that absorbs nutrients and disposes of waste; it is a key regulatory centre for the immune system.
One fascinating quote from that era feels modern:
"To promote digestion and nutrient absorption, it is beneficial to rest for 30 to 60 minutes both before and after meals.”
The gut microbiome and autoimmune rheumatic diseases
The gut microbiome refers to the trillions of microorganisms living in your digestive tract that play a key role in immune regulation and inflammation. They actively:
Train and regulate your immune system by teaching it to distinguish between harmful and beneficial substances.
Produce Short-Chain Fatty Acids (SCFAs) like butyrate, which are essential to nourish your gut cells and protect the gut barrier
Modulate systemic inflammation
Supporting the production of B vitamins (B1, B9, B12), and vitamin K
Studies have shown a pattern of dysbiosis across multiple autoimmune rheumatic diseases, including RA, Sjögren’s disease, psoriatic arthritis, spondyloarthritis, and lupus:
Decreased microbial diversity where the gut ecosystem has less resilience and variety.
Loss of beneficial bacteria: A reduction in species that produce short-chain fatty acids (SCFAs), which are vital for gut health.
Overgrowth of pro-inflammatory species: Elevated levels of bacteria like Prevotella copri have been specifically linked to immune activation and the onset of early Rheumatoid Arthritis (RA).
Compromised Gut Barrier (referred to as"Leaky Gut"): Increased intestinal permeability allows potentially harmful substances to cross into the bloodstream, thereby triggering systemic inflammation.
Furthermore, an imbalance in the oral microbiome has been associated with a higher risk of systemic complications in RA and Sjögren.
These findings suggest a potential therapeutic opportunity within the gut–oral–immune axis for treating autoimmune diseases.
What types of dietary patterns disrupt this process?
How the Western diet affects gut health and inflammation in autoimmune disease
The Standard Western Diet is characterized by excessive consumption of ultra-processed foods, refined carbohydrates, added sugars, an unbalanced intake of Omega-3 and Omega-6 fatty acids, excessive intake of red meat, and a low fibre intake (“fibre gap”).
The Western Diet consistently:
Reduces gut microbial diversity
Promotes pro-inflammatory bacteria
Increases intestinal permeability
Worsens systemic inflammation
This is not because any single food is "toxic," but the overall pattern starves beneficial microbes and fuels chronic immune activation.
Anti-Inflammatory Diet for Sjogren's Disease
Learn more about the impact of inflammatory foods on Sjogren's.
Fortunately, not all dietary patterns disrupt the gut microbiome.
Does the Mediterranean Diet reduce inflammation?
The Mediterranean dietary pattern (MedDiet) is conditionally recommended for RA as it may alleviate pain and improve fatigue with low to moderate evidence certainty.
However, it does not impact physical function or disease activity, and adherence may be influenced by patient preferences, cost, access, and burden.
Yet, the MedDiet remains one of the healthiest, most sustainable, and evidence-based lifestyle models for managing chronic inflammation.
The Mediterranean Pattern works because of its focus on:
Fibre diversity: Promotes whole grains, fruits, vegetables, nuts, and legumes.
Healthy fats: Primary use of Extra-Virgin Olive Oil (associated with anti-inflammatory markers), fatty fish, nuts, and avocados.
Antioxidants and phytochemicals from plant-rich foods.
Sustainability and adherence: It is a flexible lifestyle, not a rigid, restrictive diet.
8 Ways to Start Your Mediterranean Diet
The much-lauded MedDiet is more of a lifestyle than a deprivation or elimination diet.
This is also why isolated interventions like probiotics or supplements cannot replace an overall dietary pattern with anti-inflammatory components.
Do probiotics help RA and Sjögren’s?
In rheumatoid arthritis, Lactobacillus strains have shown modest benefits in reducing inflammatory markers and pain scores.
Evidence in Sjögren’s disease remains mixed.
Probiotics do not provide consistent effects.
Fibre diversity matters far more for long-term gut health.
At the other extreme, some people turn to highly restrictive elimination diets, desperately seeking symptom relief.
Does the Autoimmune Protocol (AIP) diet reduce inflammation?
The Autoimmune Protocol (AIP) diet, while claimed as a personalized elimination tool to potentially reduce inflammation and improve quality of life in conditions like Hashimoto thyroiditis and Inflammatory Bowel Disease, is highly restrictive.
The AIP diet requires expert guidance to mitigate the risk of nutrient deficiencies in vitamins B1, B2, B3, folate, B12, riboflavin, iron, vitamin D, and calcium.
Unfortunately, the evidence supporting the use of the AIP diet in RA is currently insufficient.
A pilot study found that 4 of 9 participants experienced improvement in fatigue, pain, and sleep; however, participants had to be on stable medication and supplements for 8 weeks.
The AIP diet should be seen as a complementary therapy, not a replacement for arthritis treatments, and should be guided by a nutritional professional. There is no evidence on its long-term impact.
Fact Check Your Fork
In this podcast episode, the Arthritis Dietitian and the Arthritis Foundation explore common arthritis and diet myths and separate science from fiction.
Fibre, inulin, and methotrexate response in Rheumatoid Arthritis
When gut bacteria ferment dietary fibres, they produce Short-Chain Fatty Acids (SCFAs), especially Acetate, Propionate, and Butyrate.
These compounds are vital because they:
Strengthen the gut barrier and reduce intestinal permeability.
Regulate immune tolerance and modulate T-cells.
Lower inflammatory signalling throughout the body.
Lower SCFA production has been observed in both rheumatoid arthritis and Sjögren’s disease and is associated with immune dysregulation.
Fibre can be a powerful immune-regulating nutrient, but it's highly underutilized.
A 2025 randomized, double-blind, placebo-controlled trial (the Superfibre Trial) found that supplementing 12 g/day of inulin improved methotrexate response rates in people with RA.
Participants receiving inulin showed greater reductions in disease activity (DAS28), particularly among those taking methotrexate.
Suggesting that gut-derived SCFAs, such as butyrate, may enhance methotrexate efficacy through immune modulation.
This does not mean fibre supplements are a magic solution.
It means that gut-supportive nutrients can be a complementary therapy to medical treatment.
How to increase fibre safely in rheumatoid arthritis and Sjögren’s disease
While the Superfibre Trial used an inulin supplement, this doesn’t mean everyone with rheumatoid arthritis or inflammatory arthritis should start taking fibre supplements.
Gut-supportive fibre is best introduced through food first, and gradually, especially if you live with flares, IBS-type symptoms, gastroparesis, or Sjögren’s disease.
A gentle, flare-safe approach looks like this:
Prioritizing fermentable fibres and resistant starches from foods such as oats, barley, lentils, chickpeas, beans, bananas, kiwi, cooked-and-cooled potatoes or rice, onions, garlic, asparagus, and flax or chia seeds.
Increasing fibre slowly, preferably over weeks rather than days.
Choosing softer, well-cooked, or blended fibre-rich foods during flares (soups, stews, porridges, smoothies).
Using small portions of higher-fermentable foods initially.
Considering fibre supplements like inulin or psyllium only when food intake is low, or tolerance is poor, starting with very low doses, preferably under professional guidance.
The goal is gradually increase gut tolerance of fermentable fibre to support SCFA production, gut barrier integrity, and immune regulation, without triggering symptoms or flares.
Here is a recipe I developed for Arthritis Society Canada to get you started on closing your fibre gap.
So, if fibre and gut diversity support immune regulation, the next logical question becomes:
How to apply gut–immune nutrition gently without another restrictive diet
The evidence on the gut microbiome, inflammation, and immune regulation is growing, but it becomes meaningful only when it can be applied in the real-world, especially for individuals living with autoimmune rheumatic diseases.
This is exactly why I created the GLOW Method™.
Instead of rigid food rules or extreme elimination diets, GLOW is a gentle, sustainable, and guilt-free approach to support individuals with autoimmune rheumatic diseases, centred on four supportive pillars.
Evidence Snapshot: Gut Microbiome and Autoimmune Rheumatic Diseases
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Frequently Asked Questions
Quick answers to common questions about diet, gut health, and autoimmune disease:
Can diet cure autoimmune diseases like RA or Sjögren’s?
No. Diet cannot cure autoimmune diseases, but it can meaningfully influence inflammation, gut health, fatigue, metabolic health, and quality of life.
Is the gut microbiome linked to rheumatoid arthritis and Sjögren’s?
Yes. Research consistently shows changes in the gut microbiome (dysbiosis), including reduced microbial diversity, altered short-chain fatty acid (SCFA) production, and increased gut permeability.
Is the Mediterranean diet good for autoimmune disease?
Yes. It is one of the most consistently supported approaches for reducing inflammation and supporting gut health in autoimmune conditions.
Does the Autoimmune Protocol (AIP) work?
The AIP diet may improve symptoms in the short term for some individuals. However, it is highly restrictive and not designed to be followed long-term without professional guidance.
Do probiotics help autoimmune disease?
Some strains may modestly improve inflammation and symptoms. However, overall dietary patterns, especially fibre diversity, have a more consistent and lasting impact on gut health. There is currently insufficient evidence to support the use of specific probiotics for the prevention or management of autoimmune rheumatic diseases.
Final Thoughts
Nutrition is not a cure for autoimmune disease.
But it is a powerful, modifiable, and complementary therapy we have to support immune regulation, gut integrity, inflammation control, energy levels, and quality of life.
Food should not become another source of stress, fear or failure.
Nutrition should become part of a supportive, realistic care pland that works with your autoimmune body, not against it.
Start with a Gentle Reset
If you’d like a simple place to begin, you’re invited to join my free Kitchen Refresh, a gentle, practical way to start applying these concepts in your everyday routine.
You’ll learn how to:
Build more supportive, anti-inflammatory meals
Stock your kitchen with gut-friendly staples
Take small, realistic steps without restriction or overwhelm
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