11 Common Types of Autoimmune Diseases

The immune system is a vast network of cells, tissues and organs. A functioning immune system safeguards the body against bacteria, viruses and infection and facilitates healing.

Autoimmunity occurs when the immune system becomes confused and mistakes the body's own cells as dangerous invaders. It then releases antibodies to kill the suspect cells, causing inflammation and damage. More than 100 autoimmune disorders are known and they affect nearly every part of the body.

Each of these disorders behaves differently and has distinct symptoms. However, some effects—including sexual health implications—are prevalent across conditions. These include low libido, erectile dysfunction (ED) and difficulty with orgasm.

Depression, anxiety, chronic pain, chronic fatigue and diminished self-confidence—all of which are also common with autoimmunity—can inhibit sexual health as well.

Certain conditions, including those that impact the nervous, endocrine and exocrine systems, can have more profound and direct impacts on sex and fertility.

The exact causes of autoimmunity aren't known, but experts believe a combination of genetics, environment and lifestyle factors may contribute. Women are twice as likely as men to develop autoimmunity generally. They are approximately 10 times as likely to develop certain autoimmune conditions such as lupus.

The reason isn't clear, but scientists believe genetics and hormones—estrogen, specifically—likely play roles.

All autoimmune diseases are chronic and incurable, but most can be managed with medical care and health-conscious habits.

11 common autoimmune disorders

Of all the many autoimmune disorders, a few are more prevalent, including the 11 explained below. The symptoms of autoimmune diseases vary by the disorder.

1. Addison's disease

Also known as adrenal insufficiency, Addison's disease occurs when the adrenal glands don't produce enough aldosterone, cortisol or androgen hormones. Cortisol, best known as the "stress hormone," is detrimental in excess, but too little of it is equally harmful. The hormone helps the body and brain use and store carbohydrates and repair tissues.

Aldosterone helps maintain water and salt balance in the kidneys. Without enough of this hormone, the body has insufficient sodium, and excess potassium accumulates in the bloodstream.

Usually, Addison's disease progresses gradually over months, according to Mayo Clinic. Initially, symptoms tend to be mild until a trigger, such as an illness or injury, kicks the disease into high gear. However, this process can occur abruptly in a phenomenon known as acute adrenal failure. In that case, it becomes a medical emergency.

Unaddressed, Addison's can become life-threatening. Symptoms include:

• Extreme weakness
• Fatigue
• Salt craving
• Low blood sugar
• Low blood pressure
• Loss of appetite
• Weight loss
• Nausea
• Vomiting
• Diarrhea

2. Celiac disease

Celiac disease, also called celiac sprue, occurs when the body has an adverse reaction to gluten, a protein found in certain cereal grains, primarily wheat, rye, barley and triticale. According to the Celiac Disease Foundation (CDF), when a person with celiac disease consumes gluten, the immune system attacks the small intestine and inhibits nutrient absorption.

Celiac disease is not the same as gluten intolerance; the latter is a sensitivity, not an autoimmune condition.

The primary symptoms of celiac disease include diarrhea, stomachaches, bloating, indigestion and constipation. Untreated celiac disease can cause serious health complications. People with this disorder are twice as likely to develop coronary artery disease and four times more likely to have small bowel cancers, according to the CDF.

3. Graves' disease

With Graves' disease, an autoimmune response causes the thyroid—an endocrine gland in the neck—to work overtime. The condition is the most common cause of hyperthyroidism, or overactive thyroid. Thyroid hormones influence multiple bodily processes, most notably metabolism.

Excess thyroid hormone, according to the American Thyroid Association (ATA), can cause symptoms such as:

• A racing heartbeat
• Insomnia
• Weight loss
• Muscle weakness
• Heat intolerance
• Nervousness
• Hand tremors

Approximately 30 percent of people with Graves' disease develop Graves' ophthalmopathy, which can result in exophthalmos, or bulging eyes. The condition can also cause erectile dysfunction, low libido and infertility if it is left untreated.

In men, it may affect sperm count and quality; in women, it can inhibit ovulation.

4. Hashimoto's thyroiditis

Hashimoto's thyroiditis is the most common cause of hypothyroidism, or underactive thyroid, in the United States. As with Graves' disease, the condition involves the immune system attacking the thyroid gland. With Hashimoto's, though, the thyroid doesn't produce enough hormones.

Symptoms include fatigue, weakness, depression, dry skin, sensitivity to cold, hair loss and weight gain. The disorder can also diminish libido and fertility in everyone. Men can experience diminished sperm count and motility, and altered sperm shape. Women may experience inconsistent ovulation and an increased risk of pregnancy complications, such as miscarriage.

Thyroid hormone supplementation may resolve these problems for many patients.

5. Inflammatory bowel disease (IBD)

Inflammatory bowel disease (IBD) is a term that encompasses two conditions characterized by inflammation in the walls of the gastrointestinal tract.

The first, ulcerative colitis, affects only the large intestine and rectum. The other, Crohn's disease, can cause inflammation in any part of the digestive system.

IBD is most prevalent in North America and Western Europe and becoming more common in these and other regions. Scientists have yet to determine why, but genetic, environmental and lifestyle factors are likely at play, according to Hana Patel, M.B.B.S., a general practitioner and mental health coach in London.

"More research is being done into Crohn's as to why the disease is more prevalent in urbanized societies. This has led researchers to propose that increased industrialization and sanitation also play a role," Patel wrote in an email interview.

She added that the Western diet—characterized by large quantities of red meats, refined carbohydrates and ultra-processed foods and beverages—may contribute, too.

6. Multiple sclerosis

In someone with multiple sclerosis (MS), the immune system attacks the myelin, a protective layer that surrounds the brain and spinal cord nerves. This damages the sheath—and sometimes the underlying nerves—and disrupts communication between the brain and body.

There are two main types of MS: relapsing-remitting and primary progressive. The condition is most common in North America and Northern Europe, far from the equator. For this reason, scientists have theorized that sunlight, or a lack thereof, may be a contributing factor.

MS symptoms include:

• Numbness in the extremities (usually the legs)
• Vision loss
• Weakness
• Balance issues
• Difficulty walking

About 50 percent of people with MS have trouble walking within 15 years of the disease's onset. Some people with MS experience erectile dysfunction, loss of sensation in the genitals and difficulty with orgasm.

7. Psoriasis/psoriatic arthritis

Skin cells usually grow and fall off each month, making way for new cells. With psoriasis, the immune system creates inflammation that causes skin cells to proliferate and accumulate instead of shedding.

There are different kinds of psoriasis, each with distinct characteristics. About 80 percent to 90 percent of people with psoriasis have plaque psoriasis, characterized by thick, discolored plaques and scales that usually appear on the elbows, knees and scalp. These raised patches can be itchy or painful.

About 30 percent of people with psoriasis develop psoriatic arthritis, which causes swelling, stiffness and joint pain, according to the National Psoriasis Foundation (NPF). Arthritis can cause permanent joint damage, disfigurement and disability if it is not treated.

8. Rheumatoid arthritis

Rheumatoid arthritis (RA) is the second-most prevalent type of arthritis next to osteoarthritis (OA), which is not an autoimmune condition. In RA, the immune system attacks the joints, usually several simultaneously, causing inflammation, pain and stiffness.

As a systemic disease, unmanaged rheumatoid arthritis can progress and inflict widespread damage to multiple body parts, including the heart, lungs, skin, eyes and nerves.

RA is usually diagnosed in people ages 40 to 60 but can occur as early as adolescence. The inflammation from rheumatoid arthritis may cause ED and vaginal dryness. As with other forms of arthritis, mobility restrictions and chronic pain can also hinder sex and intimacy.

9. Type 1 diabetes

Previously known as juvenile diabetes or insulin-dependent diabetes, type 1 diabetes occurs when the immune system attacks the pancreas. As a result, the pancreas produces little or no insulin, a hormone that helps cells take in sugar to use as energy. Without sufficient insulin, the sugar can accumulate in the bloodstream and lead to various health issues.

Unaddressed, type 1 diabetes can be life-threatening. It accounts for about 5 percent to 10 percent of cases of diabetes and is usually diagnosed in childhood but can develop at any age.

Type 1 diabetes symptoms include:

• Extreme thirst
• Frequent urination
• Fatigue
• Weight loss
• Itchiness in the genital area or frequent yeast infections
• Blurred vision

In addition to heart and blood vessel diseases, nerve and kidney damage, and other complications, type 1 diabetes can pose problems to fertility and pregnancy. With proper medical care, parents can have healthy pregnancies, according to Dyese Taylor, M.D., an OB-GYN and high-risk maternal-fetal medicine physician at Atlantic Maternal Fetal Medicine in Morristown, New Jersey.

"Decades ago, having type 1 diabetes and being pregnant used to be associated with grim outcomes for mom and baby. High blood sugar levels before and in the early weeks of pregnancy can increase the risk of miscarriage and abnormal development of the baby's body," Taylor said in an email interview. "High blood sugar levels throughout the pregnancy can negatively affect the baby, such as causing the baby to grow too big or too small, and can even be fatal to the baby."

However, Taylor continued, a doctor who specializes in high-risk pregnancies and diabetes management can help to manage blood sugar levels and mitigate risks.

10. Sjögren's syndrome

With Sjögren's syndrome, the immune system attacks the mucous membranes and glands that produce fluids such as tears and saliva. It typically begins in the mouth and eyes but can spread to other body parts, including the vagina. It frequently co-occurs with other autoimmune disorders, such as rheumatoid arthritis or systemic lupus erythematosus.

Most people with the condition are women older than age 40.

Besides dry mouth and eyes, other symptoms include fatigue, vaginal dryness, a persistent cough, skin rashes or dry skin, joint pain and swelling, and swollen salivary glands, according to Mayo Clinic.

11. Systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is the most common kind of lupus. Lupus is usually associated with a skin rash, but SLE's widespread inflammation can affect various tissues, joints and organs. Besides rashes, people typically experience joint pain and swelling and fatigue. SLE is about 10 times more common in women than in men and disproportionately affects people of color.

There's much overlap between systemic lupus erythematosus and rheumatoid arthritis, and they can co-exist, according to Elliot Rosenstein, M.D., one of the directors of the Institute for Rheumatic & Autoimmune Disease at Overlook Medical Center in Summit, New Jersey.

However, lupus generally affects the kidneys and central nervous system, whereas RA doesn't. Conversely, lupus can affect the joints but doesn't usually cause substantial, permanent anatomical changes as is typical with RA.