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 usually protects you from diseases and infections. When it senses these pathogens, it creates specific cells to target foreign cells.

Usually, your immune system can tell the difference between foreign cells and your cells.

But 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.

Some autoimmune diseases target only one organ. Type 1 diabetes damages your pancreas. Other conditions, such as systemic lupus erythematosus, or lupus, can affect your whole body.

Below we provide an overview of some of the most common autoimmune diseases.

Doctors don’t know exactly what causes the immune system to misfire. Yet some people are more likely to get an autoimmune disease than others.

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

  • Your sex: People assigned female at birth between the age of 15 and 44 are more likely to get 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 people in certain groups. 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 nutrients may impact 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. 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 14 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. This can include your:

  • heart
  • kidneys
  • eyes
  • nerves

2. Rheumatoid arthritis (RA)

In RA, your immune system attacks the joints. This causes symptoms affecting the joints such as:

  • swelling
  • warmth
  • soreness
  • stiffness

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. Psoriasis/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. This can cause joint symptoms that include:

  • swelling
  • stiffness
  • pain

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.

This damage can lead to:

  • numbness
  • weakness
  • balance issues
  • trouble walking

Different forms of MS progress at different rates. Difficulties with walking are one of the most common mobility issues with MS.

5. Systemic lupus erythematosus (SLE)

Although doctors in the 1800s first described lupus as a skin disease because of the rash it commonly produces, the systemic form, which is most common, actually affects many organs. This can include your:

  • joints
  • kidneys
  • brain
  • heart

Common symptoms can include:

  • joint pain
  • fatigue
  • rashes

6. Inflammatory bowel disease

IBD describes conditions that cause inflammation in the lining of the intestinal wall. Each type of IBD affects a different part of your gastrointestinal (GI) tract.

Common symptoms of IBD can include:

  • diarrhea
  • abdominal pain
  • bleeding ulcers

7. Addison’s disease

Addison’s disease affects the adrenal glands, which produce the hormones cortisol and aldosterone as well as androgen hormones. Too little cortisol can affect how your body uses and stores carbohydrates and sugar (glucose). Too little aldosterone can lead to sodium loss and excess potassium in your bloodstream.

Common symptoms of Addison’s disease can include:

  • weakness
  • fatigue
  • weight loss
  • low blood sugar

8. 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 that may include:

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

9. Sjögren’s disease

This condition attacks the glands that provide lubrication to your eyes and mouth.

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

10. Hashimoto’s thyroiditis

In Hashimoto’s thyroiditis, thyroid hormone production slows to a deficiency. Common symptoms of Hashimoto’s thyroiditis can include:

11. 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. Muscle weakness can also affect:

  • eye movements
  • opening and closing eyes
  • swallowing
  • facial movements

12. 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. Symptoms can include:

According to the National Institute of Diabetes and Digestive and Kidney Diseases, celiac disease affects about 1% of people in the world.

13. Autoimmune vasculitis

Autoimmune vasculitis happens when your immune system attacks blood vessels. The inflammation that results narrows your arteries and veins, allowing less blood to flow through them.

14. 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’ll develop anemia, and your body’s ability for proper DNA synthesis will be altered.

It can cause symptoms that include:

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

What are 5 common symptoms of an autoimmune disorder?

Some autoimmune disorders can have similar symptoms at 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%.

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 bring down inflammation in the body.

The Healthline FindCare tool can provide options in your area if you need help finding a specialist.

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