When your immune system does its job correctly, it helps protect your body against germs like bacteria and viruses that can cause illness. But sometimes, your immune system mistakes otherwise healthy parts of your body — like your joints or your skin — as foreign cells and sends out proteins to attack them. This immune system overactivity is what causes an autoimmune disease. Some autoimmune diseases only target one part of the body, while others affect the whole body.
Doctors and scientists don’t know what causes the immune system to attack healthy cells, but risk factors for developing an autoimmune disease External Site include genetics, diet, weight, serious bacterial or viral infections (like E.coli, Hepatitis C, and measles), smoking, or exposure to chemicals. Autoimmune diseases are also becoming increasingly common External Site, and are estimated to affect anywhere from 24 to 50 million people in the United States.
The most-common autoimmune diseases

According to the American Autoimmune Related Diseases Association, there are more than 100 autoimmune diseases External Site that affect a wide range of body parts. Some of the most common are:
- Rheumatoid arthritis. A condition where the immune system attacks the joints, which causes inflammation, swelling, pain, and, if untreated, permanent damage. Rheumatoid arthritis is different than osteoarthritis, which commonly affects older adults.
- Lupus. Occurs when the body produces autoimmune antibodies that attach to various tissues throughout the body, including the joints, lungs, blood cells, nerves, and kidneys.
- Ulcerative colitis and Crohn’s disease. Two major forms of inflammatory bowel disease, where the immune system attacks the intestinal lining and causes diarrhea, bleeding, abdominal pain, fever, and weight loss. This type of autoimmune disease is one of the top-10 conditions impacting the millennial generation.
- Multiple sclerosis or MS. Happens when the body’s immune system attacks healthy nerve cells, which can cause several symptoms including pain, weakness, poor coordination, muscle spasms, and even blindness.
- Type 1 diabetes. Caused when the immune system destroys cells that make insulin in the pancreas. Symptoms can appear suddenly and include increased thirst, frequent urination, extreme hunger, unintended weight loss, fatigue or weakness, and blurred vision.
- Psoriasis. A more visible autoimmune disorder that occurs when immune system blood cells collect in the skin, which causes skin cells to reproduce much faster than normal and leads to silvery, scaly plaques on the skin.
- Graves’ disease. Diagnosed when immune system antibodies stimulate the thyroid gland to overproduce the thyroid hormone (hyperthyroidism), which can cause weight loss, irritability, rapid heart rate, and more.
- Hashimoto’s thyroiditis. Produces the opposite effect of Grave’s disease. Immune system antibodies attack the thyroid gland and destroy the cells that produce the thyroid hormone, which significantly lowers the levels (hypothyroidism) over a period of months to years. Symptoms can include fatigue, depression, dry skin, weight gain, and sensitivity to cold.
Symptoms of autoimmune diseases
It can be difficult to diagnose autoimmune diseases because there is still so much that doctors don’t know. However, different autoimmune diseases affect different parts of the body, so early symptoms are often the same across the board. These can include a combination of:
- Tiredness or fatigue
- Difficulty concentrating
- Joint pain and swelling
- Skin problems like recurrent rashes
- Muscle aches
- Hair loss
- Gastrointestinal distress and abdominal pain
- Recurring fever
- Swollen glands
- Unexplained weight gain or loss
If you experience any of those symptoms suddenly, or they come and go at random, it’s best to speak to your personal doctor. They can order a blood test that looks for levels of antinuclear antibodies — the antibodies that attack healthy cells. However, this test, even if it’s positive, will only tell you that you might have an autoimmune disease — and can’t tell you which one.
Treatments for autoimmune diseases
There are not any cures for autoimmune diseases. Most treatment plans aim to reduce pain and inflammation with nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen and naproxen. Your doctor may want to help control your overactive immune system with immunosuppressing drugs, which are often highly regulated and expensive treatments that may require prior approval from your health insurance company.
There are also treatments that help manage certain symptoms like digestive pain, swelling, and skin rashes. Doctors may also suggest making some lifestyle changes, such as modifying diet and exercise, to help relieve symptoms.
Working with your health care provider
Diagnosing an autoimmune disease can be an extremely difficult process, which is why having a good relationship with your personal doctor is important. Your personal doctor knows you and your health history, and may also know specific specialists who can help treat your symptoms. If you don't have a personal doctor, you can find one in your health plan network by using the tools available with myWellmark® Opens New Window. You can also use myWellmark to advocate for your health, check costs before appointments, review claims, and stay up-to-date on your health plan.
