Autoimmune diseases are conditions in which your immune system mistakenly damages healthy cells in your body. Types include rheumatoid arthritis, Crohn’s disease, and some thyroid conditions.

Your immune system has the job of protecting you from diseases and infections. When it detects a problem, it sends immune cells to sort out the issue.

Usually, your immune system can tell the difference between foreign cells and your body’s own cells.

However, if you have an autoimmune disease, your immune system mistakes parts of your body, such as your joints or skin, as foreign. It releases proteins called autoantibodies that attack healthy cells.

Doctors don’t know exactly what causes autoimmune diseases. Yet some people are more likely to be affected than others.

Some factors that may increase your risk of developing an autoimmune disease include:

  • Your sex: People assigned female at birth between the ages of 15 and 44 years are more likely to develop an autoimmune disease than people assigned male at birth.
  • Your family history: You may be more likely to develop autoimmune diseases due to inherited genes, though environmental factors may also contribute.
  • Environmental factors: Exposure to sunlight, mercury, chemicals like solvents or those used in agriculture, cigarette smoke, or certain bacterial and viral infections, including COVID-19, may increase your risk of autoimmune disease.
  • Ethnicity: Some autoimmune diseases are more common in certain ethnicities. For example, White people from Europe and the United States may be more likely to develop autoimmune muscle disease, while lupus tends to occur more in people who are African American, Hispanic, or Latino.
  • Nutrition: Your diet and nutrient intake may affect the risk and severity of autoimmune disease.
  • Other health conditions: Certain health conditions, including obesity and other autoimmune diseases, may make you more likely to develop an autoimmune disease.

Different autoimmune diseases may have similar early symptoms. These can include:

With some autoimmune diseases, including psoriasis or rheumatoid arthritis (RA), symptoms may come and go. A period of symptoms is called a flare-up, and a period when the symptoms go away is called remission.

Individual autoimmune diseases can also have their own unique symptoms depending on the body systems affected. For example, with type 1 diabetes, you may experience extreme thirst and weight loss. Inflammatory bowel disease (IBD) may cause bloating and diarrhea.

Researchers have identified more than 100 autoimmune diseases. Here are 10 more common ones.

1. Type 1 diabetes

Your pancreas produces the hormone insulin, which helps regulate blood sugar levels. In type 1 diabetes, the immune system destroys insulin-producing cells in your pancreas.

High blood sugar from type 1 diabetes can damage the blood vessels and organs.

2. Rheumatoid arthritis (RA)

In RA, your immune system attacks the joints, which can lead to swelling and stiffness in these areas.

While RA more commonly affects people as they get older, it can also start as early as your 30s. A related condition, juvenile idiopathic arthritis, can start in childhood.

3. Psoriatic arthritis

Skin cells grow and then shed when they’re no longer needed. Psoriasis causes skin cells to multiply too quickly. The extra cells build up and form inflamed patches. On lighter skin tones, patches may appear red with silver-white scales of plaque. On darker skin tones, psoriasis may appear purplish or dark brown with gray scales.

Up to 30% of people with psoriasis also develop psoriatic arthritis.

4. Multiple sclerosis

Multiple sclerosis (MS) damages the protective coating surrounding nerve cells (myelin sheath) in your central nervous system. Damage to the myelin sheath slows the transmission speed of messages between your brain and spinal cord to and from the rest of your body.

Different forms of MS progress at different rates. Difficulty walking is one of the most common mobility issues in MS.

5. Inflammatory bowel disease

IBD refers to conditions that cause inflammation of the intestinal lining. There are two types of IBD that affect different parts of your gastrointestinal (GI) tract.

6. Graves’ disease

Graves’ disease attacks the thyroid gland in your neck, causing it to produce too much of its hormones. Thyroid hormones control the body’s energy usage, known as metabolism.

Having too much of these hormones revs up your body’s activities, causing symptoms like a rapid heart rate and unintentional weight loss.

Some people with Graves’ disease may also experience symptoms affecting the skin (Graves’ dermopathy) or eyes (Graves’ ophthalmopathy).

7. Sjögren disease

This condition attacks the glands that lubricate your eyes and mouth.

The hallmark symptoms of Sjögren disease are dry eyes and dry mouth, but it may also affect your joints or skin.

8. Myasthenia gravis

Myasthenia gravis affects nerve impulses that help the brain control muscles. When the communication from nerves to muscles is impaired, signals can’t direct the muscles to contract.

The most common symptom is muscle weakness. It may worsen with activity and improve with rest.

9. Celiac disease

People with celiac disease can’t eat foods containing gluten, a protein found in wheat, rye, and other grain products. When gluten is in the small intestine, the immune system attacks this part of the GI tract and causes inflammation.

People with celiac disease may experience digestive issues after consuming gluten.

According to the National Institute of Diabetes and Digestive and Kidney Diseases, celiac disease affects about 1% of the global population.

10. Pernicious anemia

Pernicious anemia may happen when an autoimmune disorder causes your body to not produce enough of a substance called intrinsic factor. Having a deficiency in this substance reduces the amount of vitamin B12 your small intestine absorbs from food. It can cause a low red blood cell count.

Without enough of this vitamin, you may develop anemia, and your body’s ability for proper DNA synthesis may be altered.

This rare autoimmune disease typically occurs in people ages 60 to 70 and older.

Can an autoimmune disease be cured?

Generally speaking, autoimmune disorders cannot be cured. They can, however, be managed with medications and other treatments.

Researchers are continuing to look for better treatments, so the answer to this question may change in the coming years.

What is the average life expectancy of someone with an autoimmune disease?

There are over 80 different types of autoimmune disorders, and most are not life threatening. People can expect to live full lives with no shortening of typical life expectancy.

What are 5 common symptoms of an autoimmune disorder?

Some autoimmune disorders can share similar symptoms in their early stages. These can include fatigue, dizziness or lightheadedness, low grade fever, muscle aches, and swelling.

What is the most serious autoimmune disease?

Many researchers recognize giant cell myocarditis, a rare autoimmune condition that can lead to heart failure, as one of the most serious autoimmune diseases. It has a 1-year mortality rate of 70%, meaning that only 30% of people with it survive over 1 year.

What are the most common autoimmune disorders?

The most common autoimmune diseases are psoriatic arthritis, rheumatoid arthritis, connective tissue diseases, multiple sclerosis, autoimmune thyroid diseases such as Hashimoto’s, celiac disease, and inflammatory bowel disease.

The symptoms of autoimmune diseases often overlap, complicating diagnoses.

Blood tests that look for autoantibodies can help doctors diagnose these conditions. Treatments include medications to calm the overactive immune response and reduce inflammation throughout the body.