Why Do Women Get Autoimmune Disease More Than Men? The Science Explained

She saw six different doctors over four years. She was told she was anxious. She was told she was hormonal. She was told to try yoga. She had lupus.

Her story is not unusual. In fact, it is so common that researchers have a name for it: the diagnostic delay. If you have ever wondered why your autoimmune disease symptoms were dismissed as “just stress” or “hormones,” the answer lies deep in our biology.

In February 2024, Stanford Medicine published a landmark study in the journal Cell that identified a major biological mechanism behind why women make up roughly 80% of all autoimmune disease patients [1]. The key player is a molecule found in every single female cell — and it has been hiding in plain sight for decades [2].

This post breaks down what the science says about your body, and what you can do about it today.

Autoimmune disease statistics in women: the numbers that should shock you

Before we get into the biology, let us look at the scale of the problem.

Autoimmune diseases — conditions where the immune system mistakenly attacks the body’s own tissues — are not rare. They affect an estimated 3–10% of the global population and are the third most common category of disease in industrialised countries, behind only cardiovascular disease and cancer [3].

And they disproportionately affect women. By a significant margin.

Autoimmune Condition	Approximate Female-to-Male Ratio
Sjögren’s Syndrome	~6 women : 1 man
Systemic Lupus Erythematosus (SLE)	~9 women : 1 man
Hashimoto’s Thyroiditis	~7 women : 1 man
Rheumatoid Arthritis	~3 women : 1 man
Multiple Sclerosis	~3 women : 1 man

Ratios vary by study and population. Source: Fairweather et al., Journal of Clinical Investigation, 2024 [3].

You probably know someone with one of these conditions. For many years, the medical world could not fully explain this skew. That is starting to change.

The X chromosome connection: the molecule in every female cell

If you are searching for the reason why women get autoimmune disease more than men, you have to look at chromosomes. Until 2024, a molecule called XIST was not widely discussed outside of niche genetics labs — but it may be the key to one of the most important questions in medicine [2].

Women have two X chromosomes (XX), while men have one X and one Y (XY). The problem is that having two copies of these large, complex structures — and the genes they carry — could be biologically dangerous. To solve this, nature devised a solution: X-chromosome inactivation [2].

Early in development, every female cell permanently shuts down one of its two X chromosomes. This silencing is carried out by XIST (pronounced “exist”), a long non-coding RNA molecule that coats one of the two X chromosomes in each cell.

Here is where it gets important.

XIST does not work alone. It binds with dozens of proteins to form large, complex structures — and the Stanford researchers discovered that this molecular machine can sometimes generate autoantibodies: antibodies that target the body’s own tissues rather than an external threat. This is often the first step on the road to autoimmune disease.

In plain terms: The very process that keeps female cells running normally can, under certain conditions, trigger the immune system to turn against itself.

What the study did not prove — and why that matters

It is important to be precise here. The Stanford study identified XIST as a major contributor, not the sole cause, of autoimmune disease in women. Autoimmunity is influenced by multiple factors, including genetics, environment, infections, and hormones. Men also develop autoimmune diseases, which means XIST cannot be the entire explanation [2].

Perimenopause and autoimmune disease: the hormone connection

XIST is not the only biological factor at play. Oestrogen — the primary female sex hormone — has a profound and wide-ranging influence on the immune system [3].

Oestrogen receptors are found on nearly all immune cells, including T cells, B cells, and macrophages. This means the immune system is exquisitely sensitive to hormonal fluctuations [3].

When oestrogen is balanced, it supports immune regulation. It promotes the activity of T-regulatory cells — the immune system’s “peacekeepers” — that prevent excessive inflammation [3].

When oestrogen fluctuates or drops — as it does during perimenopause, postpartum, or times of significant stress — the immune system can lose some of that regulatory control. Pro-inflammatory signals can increase, and the immune system can begin to malfunction [3].

This is why so many women first notice autoimmune symptoms in their 30s and 40s, and why perimenopause can feel like a hidden trigger for women who were previously well.

When autoimmune disease symptoms in women are dismissed

Here is the part that is hardest to read — but most important to know.

Even with everything we now understand about the biology of autoimmune disease in women, the medical system is still routinely failing to diagnose it.

The average person living with an autoimmune disease sees 4 different doctors over 4.5 years before receiving a correct diagnosis [4]. For women, symptoms are frequently attributed to anxiety, stress, or depression before any objective investigation is carried out [5].

Research published in Cureus in 2025 found that gender bias continues to influence diagnostic pathways for young women, contributing to delayed recognition of serious autoimmune conditions [5]. The median time from first symptom to diagnosis for Systemic Lupus Erythematosus alone is 47 months [6].

If you have been told your symptoms are “just stress,” that is not a reflection of your health. It is a reflection of a system that was not built with women in mind.

What blood tests to ask your GP for

Knowledge is your most powerful tool in a healthcare system that does not always help. If you are experiencing unexplained fatigue, joint pain, brain fog, skin changes, or recurring infections, you do not have to accept “stress” as your answer. Here are the specific tests you can request at your next appointment:

1. ANA Panel (Antinuclear Antibodies). A broad screening test for autoimmune activity. A positive result does not confirm a diagnosis, but it opens the door to further investigation.

2. Anti-dsDNA and Anti-Ro/La Antibodies. More specific markers associated with Lupus and Sjögren’s Syndrome respectively.

3. Full Thyroid Panel. Including TSH, Free T3, Free T4, and TPO antibodies — the last of which is often missed in a standard thyroid screen.

4. Rheumatoid Factor (RF) and Anti-CCP Antibodies. If you have joint pain, morning stiffness, or swelling in your hands and feet, these two tests are essential for Rheumatoid Arthritis.

5. Inflammatory Markers. CRP (C-Reactive Protein) and ESR (Erythrocyte Sedimentation Rate) — objective markers of inflammation that are common in autoimmune disease.

Frequently asked questions (FAQ)

How long does it take to diagnose an autoimmune disease? On average, it takes 4.5 years and visits to four different doctors to receive an accurate autoimmune disease diagnosis. For women, this delay is often caused by symptoms being dismissed as stress, anxiety, or normal hormonal changes.

Can stress cause autoimmune disease? While stress alone is not the sole cause of autoimmune disease, chronic stress is a well-documented trigger. Prolonged stress increases cortisol and inflammation, which can dysregulate the immune system and trigger the onset of an autoimmune condition in someone who is genetically predisposed.

Why do autoimmune diseases flare up during perimenopause? Oestrogen is a major regulator of the immune system. During perimenopause, oestrogen levels fluctuate wildly and eventually drop. This loss of hormonal immune regulation can trigger systemic inflammation, unmasking a new autoimmune disease or causing an existing one to flare.

The bottom line

Science is finally catching up to what women have been experiencing for years.

The XIST discovery is a significant one — it gives women a real, biological reason for their symptoms. Combined with what we know about oestrogen, genetics, and environmental triggers, we are building a much clearer picture of autoimmune disease in women.

But understanding the biology is only half the battle. The other half is making sure your symptoms are heard. If you take one thing from this post, let it be this: you know your body. If something feels wrong, advocate for the tests, push for the answers, and do not let anyone tell you it is “just stress.”

Save this post. Share it with someone who has been dismissed. And if you are struggling — keep pushing for answers. The science is on your side.

This article is for educational purposes only and does not constitute medical advice. Always speak to your own healthcare provider regarding your symptoms and health concerns.

For more evidence-based women’s health content, follow me on Instagram @thesoulfulgp — where I break down complex medical research into digestible, actionable information every week.

Dr Rabia Yakoob — The Soulful GP