Almost 80% of people diagnosed with autoimmune diseases are women

Yet it's still unanswered what may account for that difference. To better understand this disparity researchers are exploring factors including hormonal changes that occur around puberty, pregnancy, and menopause, as well as gut microbe differences, and aspects of X-chromosome protein-coding genes. (Some users may encounter a paywall.)

Women typically have more robust immune responses than men

This difference helps women better combat infectious diseases, but this more turbo-charged response may also make women more vulnerable to autoimmune diseases by potentially priming their immune systems to overreact to their own cells and tissues and label them as invaders that must be destroyed. Roughly 80% of American women have autoimmune conditions.

Autoimmune disorders are one of the top 10 killers of young and middle-aged women

Studies in the US and the UK, though conducted decades ago, have underscored that autoimmune diseases, when grouped together, are a top killer of women.

More than 5 million Americans have more than one autoimmune disease

Overall, about 4.6% of the US population—15 million people—have an autoimmune condition. Some common examples include rheumatoid arthritis, psoriasis, type 1 diabetes, Grave's disease, and autoimmune thyroiditis.

Autism occurs among women, too

Males have higher rates of diagnosed autism than females, but recently scientists and people with autism have been exploring if females have been disproportionately missed in screening and if girls are perhaps masking their symptoms better, leading to missed diagnoses.

Autoimmune disease prevalence and incidence are on the rise—but no one knows why

Researchers theorize that environmental factors, including shifts to less healthy diets, air pollution, infections, stress, climate change, and exposures to xenobiotics—substances like pesticides, plastics, and toxins that incite immune responses—may all be fueling epigenetic changes to our bodies that make people's immune responses go awry.

How autoimmune diseases, which attack your own tissues and cells, work in the body

These diseases remain some of medicine's thorniest problems because the immune system can mistakenly attack almost any tissue in the body, resulting in myriad diseases, including lupus (numerous tissues affected), Hashimoto's (thyroid), and MS (the nervous system).

Autoimmune diseases affect between 5% and 10% of people worldwide, but their causes remain unknown

Autoantibodies—which attack the body—may be detectable in the body years before a patient develops symptoms, but some people may have detectable levels yet never go on to develop an autoimmune disease. This video discusses this and other unsolved mysteries with autoimmune disease.

Many patients with psoriasis develop other autoimmune diseases, too

A small study published in 2024 found that nearly three-quarters of patients with psoriasis—a condition in which the body attacks healthy skin cells—also developed autoimmune disorders including thyroid diseases, connective tissue diseases, and more, suggesting such connections between these autoimmune disorders warrant further exploration.

Twin studies suggest celiac disease is among the more genetically-linked disorders

Genetics appear to play a larger part in this condition's development than many other autoimmune disorders. Research shows a roughly 60-75% genetic probability that if one identical twin has it, the other will too. Celiac triggers a small intestine attack when people eat gluten, a protein commonly found in wheat, barley, and rye.

86 commonly used drugs, including certain antidepressants, painkillers, and immunosuppressants, have different results for men and women, according to recent research.

MS disproportionately sickens women, but men tend to have worse outcomes

Though the disease is more common in women, men's symptoms progress more quickly, with men more often diagnosed with progressive MS and men's cases typically resulting in more severe symptoms—perhaps due at least partly to more delayed diagnosis—and more severe disability over time.

Learn about the more than 100 known autoimmune diseases

Explore this resource with summaries and related resources for the dozens of autoimmune diseases defined in the medical literature. Many of these disease write-ups also have interviews with a patient with the disorder—offering a personal take about challenges, advice, and lifestyle effects.

Male pattern baldness is not solely inherited from the maternal side; its causes are still under investigation, but scientists think the genetic component of this type of hair loss involves multiple genes.

Here's why genetically identical sisters can have different colored eyes

The sequence of DNA that we inherit from our parents encodes directions for making our cells and giving us specific traits. Identical twins have the same DNA sequence, so how can one twin end up with a genetic disorder while the other twin does not? Robin Ball explains how the secret lies in X chromosome inactivation.

Rheumatoid arthritis affects about 1% of the population

Rheumatoid arthritis is an autoimmune condition leading to breakdown and inflammation of multiple joints throughout the body. This academic article provides an updated deep dive into our current cellular understanding of rheumatoid arthritis, how it is diagnosed, and the variety of medications available for treating this painful condition.

How Nobel Prize-winning research unraveled why the immune system doesn't always attack itself

The 2025 Nobel Prize was awarded to scientists who discovered how immune system soldiers are typically stopped from attacking healthy tissue. The work furthered autoimmune understanding and cancer therapies.

Females are diagnosed with MS roughly 3 to 4 times more often than males

This PBS documentary traces a filmmaker's personal journey with MS after being diagnosed at age 26. It encompasses both his efforts to stymie the disease's progression and his search for answers about the disease, when, statistically, he seemed at low risk due to his gender, lack of known family risk, and other factors.

Women's health research continues to be underfunded

Health conditions that affect women more than men get less research funding. This interactive collection of graphs details the gendered gap in health research funding. Of the conditions that affect one sex more than another, those that create the...

Women are four times as likely to be diagnosed with seasonal depression

This prevalence trend mirrors the broader incidence of depression among women and is well-documented. Researchers suggest the disparity stems from differences in hormones, social role expectations, coping mechanisms, and more. Men may also present with depression differently, and seek help less.

The gut microbiome may play a major role in autoimmune disease and symptom flare-ups

Certain unhealthy foods can promote gut bacterial growth and inflammation in the lining of the gut, potentially disrupting its lining—leading to a leaky gut that may allow pathogens to dribble out into the bloodstream, fueling further inflammation that can both cause disease flare-ups and set the stage for future disease development.

Even if you have some ASD-linked gene variations you may not develop ASD

Individual environment and life experiences affect how genes perform in the body, potentially adding methyl groups to DNA that affect their function and turning genes on and off—which may heighten or reduce disease risk.

Early menopause, occurring before age 45, can be triggered by certain risk factors

Some potential causes of early menopause include autoimmune disorders, chemotherapy, smoking, and certain surgeries that cause the body to produce lower levels of estrogen and progesterone.

The word allergy is partly derived from the Greek word 'allos' for 'other'

For people with allergies, their immune systems recognize substances as a harmful "other"—cuing an inflammatory response. This podcast explores allergy details and related topics, including how scientists are interested in if the same allergic response mechanisms could underpin other health issues, including severe, painful symptoms around the time of menstrual cycles. Since estrogen acts on white blood cells called mast cells, which leads to the release of histamines—similar to what happens during allergic responses—an understudied question is whether the same process is fueling some of the uncomfortable symptoms around menstruation. An allergist guest notes this raises questions about if antihistamine medications like Pepsid might alleviate them, something that hasn't yet been explored in clinical trials.

Common genetic disorders

As research continues, it's clear that disease and genetics go hand in hand. Here's a selection of 50 National Human Genome Research Institute (NHGRI) articles providing basic information on genetic, orphan, and rare diseases caused by mutations in DNA sequences, whether inherited from parents or brought about by outside factors.

The gaps in menopause research and their effects

Nearly all studies (99%) researching the biology of aging don’t consider menopause in their setup. A Harvard professor noted that about 75% of aging-related diseases are likely influenced by menopause. In this article, she discusses how gaps in research are negatively impacting how the medical system can effectively treat aging women. Read her analysis of the issue here.

Women are born with all the eggs they will ever produce in their lifetimes

Girls are born with an estimated 1 million to 2 million eggs in their bodies, but around 10,000 die monthly before girls hit puberty. Scientists have not yet figured out why there's such an excessive number of eggs prior to menstruation, but they've calculated that there are roughly 300,000 to 400,000 eggs left at puberty.

How one autoimmune disease patient is questing for inflammation cures

This article's writer, who has Hashimoto's Disease and characteristic symptoms from her body attacking her thyroid—like exhaustion, hair loss, and brain fog—shares big take-aways from an anti-inflammatory retreat in Italy. The writer suggests that a holistic approach to eating, sleeping, and stress management, are the only sustainable ways to lower inflammation.

Half of human DNA is inherited from each parent

Within most cells reside 23 pairs of chromosomes made of tightly wound DNA, and half of each pair is inherited from each parent. The 23rd pair consists of two X-shaped chromosomes, or one such chromosome paired with a Y chromosome, and determines biological sex.

Humans are more genetically similar to cats than to dogs

While humans are not closely related to either cats or dogs from an evolutionary standpoint, scientists find that human and cat chromosomes are organized more similarly to each other than human and dog chromosomes, making cats a better model for studying human diseases.

The sibling of someone with autism has a 20% chance of developing ASD

The disorder is strongly linked with inheritance, and research suggests that if one child has ASD, there's a one in 5 chance the next child will develop autism, which is seven times more likely than the general population.

An interactive dive into the immune system

Our bodies are equipped with an incredible system able to fight off invasive pathogens to protect us from illness. The complicated system includes lymph nodes, the spleen, bone marrow, and even the tonsils. But this same system can turn against itself, a condition known as autoimmune disorders. Follow along with this thorough, engaging explainer on the human body's defense system.

Autoimmunity is when the body attacks itself, causing inflammation

Inflammation is the body's way of healing itself, and acute inflammation saves our lives when we have injuries or infections. It increases blood flow to the affected areas to bring immune cells to fight off invaders. This often results in short-term swelling, redness, and pain.

Marriages are more at risk when the woman is sick

A study tracking 25,000 copies over 18 years revealed marriages tend to end in divorce more often when the woman is sick. Conversely, men's health issues do not impact divorce rates. Researchers noted that increased depression, potentially as a result of financial dependence, contributes to the disparity. Generally, most marriages do not end when a spouse becomes sick.

Why CAR-T therapy has become one of the main focus areas for autoimmune diseases

The therapy, originally targeting cancer, involves taking a patient's own T cells, genetically reprogramming them to recognize and attack a specific target and then infusing them back into patients. For autoimmune diseases, the therapy instead programs them to target immune cells that are causing problems, restoring immune system tolerance.

Sex determination isn't all XX and XY

We're generally taught that chromosomes determine an animal's sex, but it is way more nuanced than that. Watch this 12-minute video to find out how.

Less than 1% of aging studies consider menopause and its effects

Nearly all studies researching the biology of aging don't consider menopause in their setup. In part, that's because menopause is difficult to emulate in animal models. Menopause is uncommon in the animal world beyond humans and whales. This presents a problem for medicine and science because about 75% of aging-related diseases are likely influenced by menopause.

Why are there as many males as females?

Pretty much every species breaks down with an equal sex-ratio, with roughly the same number of males as females. But on the surface, it appears that most species wouldn't need many males to keep the population growing, with their energy-efficient, abundant sex cell production. So why is it equal? Scientists argue an equal ratio is the most evolutionarily stable. Learn about this quirk of biology here.

Adults are developing food allergies that they didn’t have as children

Research published in 2019 found that almost half of 40,000 surveyed adults with food allergies developed a new food allergy as adults, underscoring that our immune systems may newly misclassify substances later in life.