Autoimmune disorders are medical conditions in which the immune system mistakenly attacks healthy cells in the body. These disorders can affect various organs and systems, leading to a wide range of symptoms.

While there are over 80 recognized autoimmune disorders, some are more common than others. In this article, we will explore the top 10 autoimmune disorders that affect the most people worldwide.

1. Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory disorder that primarily affects the joints. It occurs when the immune system mistakenly attacks the synovium (the lining of the joints), causing pain, swelling, and stiffness.

RA can affect multiple joints and may lead to deformity and loss of function if left untreated. It affects approximately 1.3 million people in the United States alone.

2. Systemic Lupus Erythematosus (SLE)

Commonly known as lupus, SLE is a complex autoimmune disorder that can affect any part of the body, including the skin, joints, kidneys, heart, lungs, and brain.

The exact cause of SLE is unknown, but it is believed to involve a combination of genetic and environmental factors. Lupus affects women more frequently than men and usually develops between the ages of 15 and 44.

3. Type 1 Diabetes

Type 1 diabetes is an autoimmune disorder in which the immune system destroys insulin-producing cells in the pancreas. Without insulin, the body cannot regulate blood sugar levels, leading to high blood sugar.

Type 1 diabetes usually develops in childhood or adolescence, and individuals with this condition require daily insulin injections or the use of an insulin pump to survive.

4. Multiple Sclerosis (MS)

Multiple sclerosis is a chronic disease of the central nervous system in which the immune system attacks the protective covering of nerve fibers (myelin).

This disrupts the normal flow of electrical impulses between the brain and the body, resulting in a wide range of symptoms, including fatigue, muscle weakness, and problems with coordination and balance. MS affects approximately 2.3 million people worldwide.

5. Psoriasis

Psoriasis is a chronic autoimmune condition that affects the skin cells. It causes rapid skin cell growth, leading to the accumulation of thick, scaly patches on the surface of the skin. These patches can be itchy, painful, and may crack and bleed.

Psoriasis can also affect the nails, joints, and other body parts. It affects around 2% of the global population.

6. Hashimoto’s Thyroiditis

Hashimoto’s thyroiditis is an autoimmune disorder in which the immune system attacks and damages the thyroid gland. This leads to an underactive thyroid (hypothyroidism) and can cause symptoms such as fatigue, weight gain, and depression.

Hashimoto’s thyroiditis affects more women than men and often develops between the ages of 30 and 50.

7. Celiac Disease

Celiac disease is an autoimmune disorder triggered by the ingestion of gluten, a protein found in wheat, barley, and rye. In individuals with celiac disease, the immune system reacts to gluten, damaging the lining of the small intestine.

This can lead to malabsorption of nutrients and various gastrointestinal symptoms, such as diarrhea, abdominal pain, and bloating. Celiac disease affects approximately 1 in 100 people worldwide.

8. Inflammatory Bowel Disease (IBD)

Inflammatory bowel disease refers to a group of chronic inflammatory conditions of the gastrointestinal tract, including Crohn’s disease and ulcerative colitis.

These conditions occur when the immune system mistakenly attacks the lining of the digestive tract, causing inflammation and various symptoms such as abdominal pain, diarrhea, and rectal bleeding. IBD affects millions of people worldwide.

9. Sjögren’s Syndrome

Sjögren’s syndrome is an autoimmune disorder that primarily affects the salivary glands and tear glands, leading to dry eyes and dry mouth. It can also affect other parts of the body, including the joints, skin, and various organs.

Sjögren’s syndrome is more common in women and often occurs in conjunction with other autoimmune disorders, such as lupus or rheumatoid arthritis.

10. Ankylosing Spondylitis

Ankylosing spondylitis is a chronic inflammatory disease that primarily affects the spine. It causes inflammation of the joints between the vertebrae, leading to chronic pain and stiffness.

Over time, this inflammation can result in the fusion of the vertebrae, causing a permanent loss of mobility in the affected area. Ankylosing spondylitis affects approximately 0.5 to 1.0% of the global population.