The immune system helps defend your body against threats like diseases, viruses, bacteria, infections, and foreign substances, also known as antigens, which trigger an immune response.

When it encounters these antigens, it stores information and can later make antibodies to defend against these specific invaders.

But, an unhealthy immune system may have trouble fighting off threats.

If you’re immunocompromised, your immune system is less capable of producing antibodies and providing protection.

And in some cases, the immune system incorrectly recognizes the body’s own cells and tissues as antigens. When this happens, the body may produce an autoimmune response, attacking healthy cells in the body. This happens in the case of autoimmune disorders.

Below, we answer questions about the difference between people with autoimmune disorders and those who are immunocompromised.

Autoimmune disorders occur when your body’s immune response targets itself, attacking its own cells and tissues.

There are almost 100 recognized autoimmune disorders. And according to the National Institute of Health (NIH), over 24 million people in the United States have an autoimmune condition. You can be born with an autoimmune disease or develop it later in life.

Examples of autoimmune disorders include:

  • Addison’s disease: This autoimmune disorder happens when the adrenal glands don’t make certain hormones, including cortisol. It can cause weakness, fatigue, appetite loss, weight loss, and pain.
  • Celiac disease: This chronic digestive and immune disorder is caused by an intolerance to gluten and can lead to digestive problems.
  • Graves’ disease: This disease causes the immune system to attack the thyroid gland, resulting in an overproduction of thyroid hormones. Graves’ disease, which can cause hyperthyroidism, may lead to stroke, heart problems, fertility issues, eye issues, and osteoporosis.
  • Hashimoto’s disease: The most common cause of hypothyroidism in the United States, Hashimoto’s disease, can lead to high cholesterol, heart problems, and pregnancy complications. It can also lead to a rare, potentially life threatening condition called myxedema.
  • Multiple sclerosis (MS): MS is an autoimmune disease of the central nervous system that occurs when the immune system attacks the brain and spinal cord.
  • Psoriasis: The National Psoriasis Foundation shares that more than 3% of the U.S. population is affected by psoriasis. It occurs when the immune system accelerates skin cell growth and causes inflammation that results in raised plaques and scales on the skin. These skin issues can be very uncomfortable and cause pain, burning, and itching.
  • Psoriatic arthritis: This type of arthritis may infect up to one-third of people with psoriasis and can lead to permanent joint damage.
  • Rheumatoid arthritis: According to the Centers for Disease Control and Prevention (CDC), this inflammatory autoimmune disease attacks the joints. It can lead to chronic pain, organ problems, and mobility issues.
  • Systemic lupus erythematosus (SLE): A chronic autoimmune disease, lupus can cause painful inflammation in various parts of the body as it attacks healthy tissues. Lupus can affect many parts of the body, including the heart, kidneys, skin, and joints.
  • Type 1 diabetes: This autoimmune disease occurs when your body attacks the cells in your pancreas that produce insulin, a hormone that helps regulate blood sugar.

When you have an autoimmune disease, your immune system may mistakenly attack healthy cells.

Autoimmune conditions don’t necessarily cause a weakened immune system, but some medications used to treat these disorders may cause a weakened immune response.

Being immunocompromised means that you have a weakened immune system that may have trouble protecting you from things like bacteria, viruses, and fungi. Certain diseases such as AIDS, cancer, and hepatitis may cause you to become immunocompromised.

Certain medications can lead to you becoming immunocompromised. For example, immunotherapy, steroids, radiation treatment for cancer, and organ rejection medications can all leave your immune system in a weakened state.

Medications that have this effect are known as “immunosuppressive” because while they help treat a condition, they also decrease your immune system’s abilities.

Some signs that you may be immunocompromised include:

  • frequent infections
  • constant fatigue and tiredness
  • frequent colds or not recovering from a cold after 7 to 10 days
  • gastrointestinal issues like chronic diarrhea

Many factors can impact your immune system, including environmental factors and your behavior. Some things that can weaken your immune system include:

  • Unhealthy diet: According to research, diets high in saturated fats, sugars, and refined carbohydrates can contribute to chronic inflammation, which may affect your immune system’s effectiveness.
  • Excessive alcohol consumption: High alcohol consumption is associated with slower recovery from infection and wound healing. It can also lead to inflammation and organ damage.
  • Smoking: Studies show that smoking can disrupt your immune system and contribute to diseases and other health issues.
  • Stress: According to research, chronic stress may impair your immune system.
  • Not getting enough sleep: The CDC shares that lack of sleep can affect your immune system and lead to health disorders.
  • Not getting enough exercise: Regular physical activity is important for your overall health and immune system.
  • Age: Older adults may experience a decline in their immune system function.
  • Certain medications and treatments: Some medications that can weaken your immune system include corticosteroids and tumor necrosis factor (TNF) inhibitors. Doctors may prescribe these to treat autoimmune disorders.

According to the CDC, if you have a weakened immune system, you’re at higher risk of having severe outcomes or experiencing death due to illness.

Vaccines are designed to help prevent you from getting certain diseases or reduce your chance of experiencing serious complications. Common vaccines include:

  • COVID-19
  • chickenpox
  • flu
  • hepatitis B
  • human papillomavirus (HPV)
  • measles
  • mumps
  • polio
  • rubella
  • shingles

If you’re immunocompromised, it’s a good idea to talk with a doctor to determine if a vaccine is safe for you. Things to consider include:

  • whether you’ve had an allergic reaction after being exposed to an ingredient in a vaccine
  • whether you’ve had an allergic reaction after a previous dose of the vaccine
  • if you’re pregnant, whether the vaccine is safe for those who are pregnant
  • whether there are known interactions with medications you’re currently taking

And while it may be safe to get a vaccine, having a weakened immune system could limit your immune response. As a result, some vaccines may be less effective for those who are immunocompromised.

Some things that may help you improve your immunity if you’re immunocompromised include:

  • getting vaccinated
  • eating a healthy diet
  • avoiding smoking and excessive alcohol consumption
  • taking supplements
  • moderate exercise
  • getting enough sleep

Consult with a doctor to determine which steps you can safely take to potentially improve your immunity.

To help protect immunocompromised people, it’s important to be mindful of how your decisions can affect others. You may not always know who’s immunocompromised, but there are some basic things you can do to help reduce your chance of harming those who are:

  • Stay home if you’re sick: If you know you’re sick, you can help prevent transmitting the illness to the immunocompromised by avoiding public spaces and staying home when possible.
  • Wear a face mask or respirator in public places: According to the CDC, consistent use of a face mask or respirator (N95 or KN95) in indoor settings is associated with reduced transmission of diseases, including COVID-19. Correctly worn N95s and KN95s are associated with the best protection.
  • Get vaccinated: You can reduce the risk of passing diseases to at-risk people by getting vaccinated.
  • Practice good hygiene: Washing your hands with soap and water can help prevent the spread of certain diseases and bacteria.
  • Consider meeting up outdoors: A 2021 systematic review found the risk of transmitting respiratory viruses, including COVID-19, may be lower when outdoors.
  • Practice safer sex: Washing sex toys and using barrier methods like condoms can help reduce the risk of transmitting diseases.

According to research, around 2.7% of Americans are immunocompromised. These people are at greater risk for severe outcomes and death from diseases and other health threats.

If you have a weakened immune system, your doctor can help you determine the best steps to take to stay as healthy as possible. This may include getting vaccinated and forming healthy lifestyle habits.

People with healthy immune systems can help protect immunocompromised people by making choices that reduce the chances of passing on illnesses to others.