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The root cause of psoriasis

Why psoriasis begins & how it progresses

The skin is the largest organ in the body and the most visible one. It’s an incredibly complex network of cells, nerves, glands, blood vessels, and fat. It’s all housed in three distinct layers: the outermost epidermis, comprised of a spinous layer where special skin cells called keratinocytes are found; the middle dermis; and the lower fatty layer. It’s the interaction between the skin and immune cells, both in the skin and inside the body, that triggers psoriasis, a chronic disease that affects more than 7 million people of all ages in this country.

The Role of Inflammation

Psoriasis is known as a chronic inflammatory disease. This means that the disease is characterized by a normal immune response called inflammation that never shuts off. Inflammation is an essential protective tool of the immune system to fight off what it considers to be harmful like a virus, bacteria, or anything that can potentially cause injury to the body. The most common symptoms of inflammation are fever, loss of appetite, muscle stiffness, and chills. These are the symptoms that typically accompany illnesses like a cold or the flu.

Inflammation, with all its symptoms, is meant to be short term: it’s designed to turn on to get rid of the invader and turn off once it achieves this goal, with symptoms going away until the next invader appears on the scene. In those with psoriasis, however, this inflammation is occurring all the time. It’s as if the body is continually fighting off a bad virus but it’s never able to accomplish its task so it just keeps fighting. In this case, there is no invader or virus. Immune cells—particularly ones called T cells—in those with psoriasis see the body’s own skin cells as invaders and continually attack them. This self-attack on the body is why some chronic inflammatory diseases like psoriasis are called autoimmune diseases.

In the process of attacking the body’s own skin cells, the immune system is triggering even more inflammation and with it redness, itching, and swelling. This attack on the skin cells causes an acceleration of skin cell growth, so much so that skin cells in the epidermis called keratinocytes—which typically shed themselves every 28 days—are shedding themselves every three to four days. These shed cells get backed up, piling up on the surface of the skin and causing the raised plaques and scales on the skin so common in those with psoriasis.

The chronic inflammation that accompanies psoriasis often affects more than just the skin, however. It can affect other organs in the body like the brain, the heart, the lungs,
and the liver. Those who have psoriasis are more prone to cardiovascular disease, asthma, chronic obstructive pulmonary disorder, liver disease, diabetes, and osteoporosis, as well as joint pain and swelling (called psoriatic arthritis)—all chronic inflammatory diseases. What can help: doing what you can to reduce inflammation in the body, while following the treatment plan recommended by your doctor. Dietary changes, pp. 13-15, can help as can incorporating stress- reduction techniques.

Why Inflammation Becomes Chronic

Inflammation, a normal immune response in the body, can go haywire due to many factors.

  • An unhealthy diet Eating too many processed, sugary, or fried foods has been found to be a driver of inflammation in the body. Eat these foods regularly and inflammation can develop and persist.
  • Being overweight Fat releases inflammatory substances in the body; the more fat you have, the more inflammation you have. Lose the weight with a diet rich in good-for-you foods (see p. 13) and a consistent exercise program, and you’ll see flare-ups reduced.
  • Alcohol use There has been a great deal of research linking alcohol use to the development of psoriasis and, in those who have already been diagnosed, it can trigger flare-ups. Limit your alcohol use, or cut it out altogether, and you’re sure to see an improvement in your psoriasis symptoms.
  • Smoking This habit is a contributor to major diseases; psoriasis is no different. Quitting will help reduce psoriasis flare-ups.
  • Not getting enough sleep It’s during sleep that our cells repair themselves and the body rejuvenates itself. Not getting enough quality shut-eye can trigger inflammation. Lifestyle strategies that can help you sleep better: get out for fresh air and sunlight every day (morning sunlight exposure, in particular, has been shown to help), skip before-bed news, ban phone scrolling at least an hour before bed, avoid caffeine after 3 p.m., and dim bedroom lights about an hour before bed to set the stage for sleep.
  • Chronic stress Anxiety and stress are key drivers of inflammation and psoriasis flare-ups. Finding ways to reduce stress (see p. 10) can help lower inflammation overall and reduce lesions.

Understanding what can trigger your flare-ups is the first step to help manage them. Consistent treatment, as prescribed by your doctor, is the next step.

While there are distinct types of psoriasis, it is possible to have more than one type at the same time.

Plaque psoriasis is the most common type of psoriasis and is diagnosed in up to 90 percent of patients. It’s characterized by raised, itchy skin patches or plaques covered with scales.

Plaque psoriasis is the most common type of psoriasis and is diagnosed in up to 90 percent of patients. It’s characterized by raised, itchy skin patches or plaques covered with scales.

Scalp psoriasis is experienced by an average of 50 percent of patients. This type of psoriasis often looks like dandruff but can also appear as thick, crusted plaques. It can affect the areas on the scalp and around the hairline: the forehead, back of the neck, and around the ears. Many people with scalp psoriasis also have psoriatic arthritis that affects the joints.

Inverse psoriasis is one of the least common type of psoriasis with only about 7 percent of patients affected. It causes lesions in the skin folds in the groin area, the buttocks, and the breasts and is typically triggered by fungal infections.

Pustular psoriasiscan appear as pus-filled blisters on the palms and soles, but this is less common. In this same area, people can also get psoriasis on their nails. This type of psoriasis can cause pitting and white, yellow, or brown discoloration on the nails. Another less common type of psoriasis is called erythrodermic psoriasis. It causes a widespread, burning, peeling rash on the skin.