Psoriasis is a chronic, noncontagious skin condition that causes skin cells to build up and form red, inflamed patches.

Following decades of research, doctors remain unclear as to the exact causes of psoriasis. But they understand that the immune system, genetics, and environmental factors can play a key role.

This article will look at psoriasis and the immune system and how to boost immunity. It will then explore possible complications of psoriasis, as well as triggers and treatments.

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Many experts classify psoriasis as an autoimmune disorder, although others disagree. One alternative theory is that psoriasis occurs because the immune system reacts irregularly to bacteria on the skin due to genetics.

In an autoimmune disease, specific triggers cause the immune system to malfunction. These triggers vary between individuals. But in the case of psoriasis, they can include stress and skin trauma, such as insect bites, sunburn, and scratches.

In psoriasis, the activated immune system mistakenly launches an inflammatory response. It begins to attack healthy cells as though they were harmful invading pathogens. White blood cells called T helper lymphocytes, or T cells, become irregularly active and produce excess signaling molecules.

These cytokine molecules cause the blood vessels in the skin to widen. In turn, this causes white blood cells to accumulate, and keratinocytes, which make up the outer layer of the skin, to multiply much faster than usual.

In psoriasis, the process of a cell dividing, maturing, migrating to the skin’s surface, and sloughing off is complete in as few as 3–7 days, compared with 3–4 weeks in a person without psoriasis.

The result of this skin buildup is thickened, flushed, and scaly skin plaques.

Learn what psoriasis on black skin can look like here.

Learn five facts about psoriasis and the immune system here.

Psoriasis causes

There are many different types of psoriasis.

Researchers believe that a combination of factors can cause an individual to develop psoriasis.

In some cases, genetics can be a cause, as the condition often runs in families. If a child has one affected parent, they have a 16% chance of developing psoriasis. With both parents, the chance jumps to 50%.

But some individuals with no family history may also develop psoriasis. This finding highlights the effect environmental factors such as stress, smoking, and diet may have on psoriasis development.

Having psoriasis does not necessarily mean a person is immunocompromised.

But some people take medication for psoriasis that reduces immune function, called immunosuppressant drugs. This can mean a person is immunocompromised. An example of an immunosuppressant drug that doctors use to treat psoriasis is adalimumab.

Learn whether COVID-19 is more dangerous for people with psoriasis here.

Having a properly functioning immune system is essential to health.

There are various ways that individuals with psoriasis can regulate their immune systems through diet and exercise.

Mediterranean diet

According to a 2018 study, following a Mediterranean diet can slow the progression of psoriasis since it reduces inflammation.

The Mediterranean diet consists of the following:

High consumption of:Low consumption of:
vegetablesdairy products
extra-virgin olive oil


People use this yellow spice in cooking and natural medicines. Turmeric may positively impact someone’s immune response.

According to one 2017 paper, the curcumin found in turmeric has antioxidant and anti-inflammatory effects.

So, turmeric may reduce symptoms of many conditions that inflammation can worsen, including psoriasis.


Garlic may boost the immune system.

One 2014 review showed that study participants taking a placebo had over twice as many colds between them as the people taking garlic supplements.

The researchers recommended further research to confirm the immune-modulating effects of garlic.


Regular exercise can improve immune system functions.

One study found that 30–60 minutes of daily brisk walking improves the body’s defense system.

Regular exercise can also be important for people with psoriasis, as it can reduce the risk of other complications they are more likely to experience, such as high blood pressure or diabetes.

Psoriasis appears on the skin and nails, but problems with the immune system that cause psoriasis can cause other conditions alongside it.


Psoriatic arthritis, or joint inflammation, occurs in around 30% of people with psoriasis.

Psoriatic arthritis can be a painful and destructive inflammatory type of arthritis. But symptoms may reduce with treatment.

Cardiovascular disease

Psoriasis can mean a person has a higher risk of developing cardiovascular diseases such as:

This is possibly due to the inflammation that occurs with all the conditions.

Psychosocial disorders

People with psoriasis may feel emotional distress that disrupts their regular social interactions or working life.

According to a 2018 study, people with psoriasis have an increased risk of experiencing depression and anxiety.

Individuals with psoriasis may have different triggers, and the condition may run in families.

Common triggers that can cause flare-ups in people with psoriasis can include:

  • stress
  • injuries to the skin, including tattoos or shaving cuts
  • alcohol
  • smoking
  • dry, cold weather
  • sunburn and hot weather
  • infection
  • medications

Learn about the causes of psoriasis here.

If psoriasis is mild, treatment with a skin moisturizer, medicated shampoo, and exposure to sunlight may be enough to alleviate symptoms.

But most people require medical therapies to manage their psoriasis. Options include:

Topical therapies

Corticosteroid ointments, gels, and lotions of varying strengths can reduce inflammation and itching.

Long-term use of potent topical corticosteroids can cause skin thinning and damage. So, doctors may recommend forms of vitamin D and vitamin A instead of, or in conjunction with, steroid use. They may also prescribe corticosteroid-free, immune-modulating topicals for delicate areas instead.


Doctors can use UV radiation to treat moderate to severe psoriasis.

They may prescribe UVB in combination with other topical medications and reserve UVA for psoriasis that does not respond to other treatments.

Learn about light therapy for psoriasis here.

Learn about home remedies to ease psoriasis here.

Doctors remain unclear as to the exact causes of psoriasis. There is evidence for genetic involvement, as those with a family history of psoriasis are more likely to have it themselves.

Psoriasis appears to be an autoimmune response, with specific triggers causing the immune system to react against healthy tissue.

Although it cannot be cured, individuals can manage the symptoms with various therapies. These include topical corticosteroid creams, phototherapy, and biologic immunosuppressant agents.

Further research is needed to understand the inheritance and immune system involvement of psoriasis.