Well, technically, yes, psoriasis affects the skin. But it's actually caused by the immune system. People with psoriasis have excess skin cells because their immune systems send out faulty signals to the body. Instead of falling off, the cells build up on the skin and form red, scaly patches.
Psoriasis is the second most common autoimmune disease in the United States, after multiple sclerosis.
Psoriasis is the most prevalent autoimmune disease in the United States -- about 7.5 million people are affected.
No one knows what causes psoriasis.
It's true -- the cause of psoriasis has never been pinpointed, although you can be genetically predisposed to it.
Our bodies shed around 80,000 skin cells every minute.
When our bodies are working properly, we get rid of 40,000 skin cells a minute.
About 10 percent of the population has psoriasis.
Experts think about 10 percent of us are genetically predisposed to psoriasis, but only about 2 to 3 percent actually have it.
There are five kinds of psoriasis.
There are five kinds: guttate, pustular, inverse, plaque and erythrodermic.
The most common kind of psoriasis is inverse psoriasis.
About 80 percent of people with psoriasis have plaque psoriasis -- red, scaly patches that usually appear on the elbows and knees.
Guttate psoriasis is a rash of small red bumps that cover the body from the neck down.
Guttate psoriasis often starts in childhood, and it does affect the entire body below the neck.
Palmoplantar psoriasis is a form of pustular psoriasis that's linked to alcohol abuse.
Past and present smokers are the usual palmoplantar psoriasis patients. Its pustules appear on the soles of the feet and palms of the hands.
Erythrodermic psoriasis can lead to congestive heart failure.
Erythrodermic psoriasis is the most rare type -- it causes protein and fluid loss that can lead to infection, pneumonia and congestive heart failure.
Psoriasis is considered severe when it covers more than half of your body.
About a quarter of psoriasis patients have severe cases -- when it affects more than 10 percent of your body.
If you have psoriasis, you usually have three basic treatment options.
Yes, there are three options: topical or oral medication, and phototherapy.
Therapy with UVA light rays is a common psoriasis treatment.
UVA treatment does exist, but it must be combined with a medication called psoralen. UVB light can be used on its own, and many patients have their own UVB machines at home.
Psoriasis is more prevalent in African Americans than it is in Caucasians.
No, it's more common in Caucasians -- 2.5 percent versus 1.3 percent.
Psoriasis is most likely to appear when you're over 50.
Young adulthood -- between the ages of 15 and 25 -- is the most common age for the onset of psoriasis.
If both parents have psoriasis, their child has a 50-50 chance of having it, too.
A child of two psoriasis sufferers has a 50-50 chance. If one parent has it, the risk goes down to 10 percent.
Sun exposure is the biggest psoriasis trigger.
Moderate sun exposure can actually help some cases of psoriasis (although sunburn is a no-no), and there's no definite link between diet and psoriasis flare-ups.
Medications, stress and skin injuries are much more likely to trigger psoriasis.
Yes, all three are common psoriasis triggers.
If you have severe psoriasis, you have an increased risk of digestive problems.
People with severe psoriasis do have increased risk of having a heart attack.
About 10 to 30 percent of people with psoriasis will develop psoriatic arthritis.
Psoriatic arthritis develops in 10 to 30 percent of psoriasis patients, usually between the ages of 30 and 50.
Do you know why psoriasis develops, who gets it, and how to treat it? Test your knowledge about this medical skin problem with our psoriasis quiz.
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