Autoimmune diseases are sweeping the globe. Around one in 20 Australians has an autoimmune diagnosis, though this may be underestimated. Globally, their prevalence is rising by about 12.5 per cent annually, ranking autoimmune disease among the fastest-growing health concerns.
Western medicine has historically emphasised treating physical symptoms of autoimmune disease, often through prescription drugs. While medication provides pain relief to many autoimmune disease sufferers, new research suggests we may be able to reverse and even heal autoimmune diseases. A key part of this approach for many people is improving mental wellbeing.
Why inflammation goes rogue
All autoimmune diseases involve inflammation. Inflammation is normally a short-term response to injury or infection, but when unresolved, it becomes chronic and attacks the body’s own tissues. This results in various symptoms, some common to all autoimmune diseases, others specific to certain autoimmune conditions.
Autoimmune diseases tend to cluster in families, suggesting they’re heritable and driven by genetics. Yet genes alone don’t explain their development. For example, not everyone with a gene linked to coeliac disease or Hashimoto’s develops the condition. That’s because environmental and epigenetic factors — diet, stress, trauma — influence whether these genes are expressed in a way that results in autoimmunity.
Dietary triggers such as gluten, dairy and nutrient deficiencies (eg vitamin D, B vitamins and selenium) are well-documented risk factors. Other contributors include toxins, infections, smoking and certain medications or forms of exercise. But these still don’t fully account for the rise in autoimmune diagnoses. One critical overlooked factor, however, is stress and trauma.
When stress becomes biology
The landmark CDC-Kaiser Adverse Childhood Experiences (ACEs) study of more than 17,000 adults found that the more early-life adversity a person experienced, including abuse, neglect and family dysfunction, the greater the risk of developing chronic health conditions. Adults with multiple adverse experiences were 70–100 per cent more likely to develop autoimmune diseases later in life.
One of the clearest mechanisms linking trauma to autoimmunity is nervous system dysregulation. According to Dr Seyma Katrinli, an instructor and researcher at Emory School of Medicine, autoimmune diseases are particularly prevalent in people with Post-Traumatic Stress Disorder (PTSD) and CPTSD. CPTSD often results from small stresses that add up and can be considered a bulk trauma, especially in childhood, and tends to produce more pronounced dysregulation of the stress response than other mental health conditions.
This dysregulation isn’t just psychological — it’s physiological. Research shows that people with PTSD are 58 per cent more likely to develop an autoimmune disease because trauma changes how the body functions.
PTSD triggers stress hormones that activate inflammation while suppressing the calming parasympathetic nervous system, particularly the vagus nerve, which connects the brain to most major organs. This shift pushes the body into a prolonged fight, flight or freeze state. One study found that suppressing vagus nerve activity can increase immune activity up to threefold, while stimulation reduces inflammation. This suggests nervous system regulation may be one of the most powerful tools we have for managing autoimmunity.
In chronic stress, this imbalance between a hyperactive sympathetic system and an underactive parasympathetic one can become self-reinforcing. The longer it persists, the more likely it is to trigger an inflammatory cascade that leads to autoimmune disease.
But the relationship between inflammation and PTSD isn’t just one way. “It’s bi-directional,” explains Dr Katrinli. Trauma can drive inflammation, and inflammation can increase vulnerability to PTSD.
For instance, people with elevated levels of C-reactive protein (CRP), a key inflammatory marker, are more likely to develop PTSD after trauma, even before symptoms appear. Social adversity, low income and poor diet can all raise CRP levels. This suggests that chronic low-grade inflammation may act as a primer, making some people more vulnerable to developing PTSD.
Inflammation also interferes with neurotransmitter function. Dr Katrinli explains that high levels of inflammation suppress the production of dopamine and serotonin — the brain’s feel-good chemicals. When those systems are dampened, people are more likely to experience low motivation, fatigue and turn to compensatory behaviours such as emotional eating, substance use or social withdrawal — all of which further fuel inflammation.
This may help explain why women are disproportionately affected.
Why women are more vulnerable to autoimmune disease
Women are two to three times more likely to develop PTSD and about three times more likely to be diagnosed with autoimmune disease than men. This is often attributed to hormonal factors, such as oestrogen’s role in immune modulation, but biology doesn’t tell the whole story.
Sociocultural pressures, particularly the expectation that women suppress difficult emotions, also increase inflammation. Emotional suppression raises inflammatory markers and when we’re taught not to cry, complain or make a fuss, those experiences don’t disappear, they stay in the body.
For women and other marginalised groups, such as racial minorities, the combined weight of systemic stress and emotional silencing may increase vulnerability to stress-relat