What you need to know about the common condition, according to a dermatologist.

Psoriasis is an immune-mediated inflammatory disease that affects millions of people, Kim Kardashian West being just one of them.

This week the beauty magnate stepped out in Manhattan, and her shin had flared up in a manner typical to the non-contagious condition, as anyone who also suffers would know. (The itchiness? Its real.)

Photo: Getty ImagesSource:BodyAndSoul

But, while psoriasis affects 1.4 million Australians (or, around 2-4 per cent of the population, according to dermatologist Dr Natasha Cook of Darlinghurst Dermatology in Sydney) there is still a great deal of misinformation and misunderstanding among people who dont suffer from it - and even some who do.

First up, according to Dr Cook, psoriasis can cause red, scaly patches on your skin, irregular texture of your nails, and dandruff, and affects both sexes. If you think for the first time in your life you might be dealing with this, book an appointment with your GP who will be able to advise a correct treatment plan, as psoriasis can occur at any life stage to anyone (though it does tend to peak in early adulthood).

Your scalp, knees, elbows, hands, and feet are the most typically affected areas, though as Dr Cook explains it can occur anywhere on your body and as new cells mix with old cells, an accumulation on your skin occurs, which leads to raised red lesions called plaques on the body. Ouch.

According to Dr Cook, the condition has many triggers (genetic, for starters, as a third of people who are diagnosed have a family member who suffers, too) and a host of environmental and lifestyle factors can activate it, too.

Sore throats from a streptococcal infection can unmask a type of psoriasis known as guttate psoriasis, according to Dr Cook, as can trauma to the skin like bad sunburn, as can lifestyle factors smoking, excessive drinking, and being overweight can cause flare-ups, too... and another huge factor is stress, though it can still occur without these triggers at play.

According to Dr Cook, the cold weather can bring on psoriasis more than the heat (which might explain a few things, come to think of it) as winter dries out the skin more. Plus, the sun helps peoples psoriasis as it suppresses the immune system, and given this is an overactive immune disorder, it helps many cases.

And, while it cant be solved with a contour kit (sadly) there are certainly things you can do to keep the symptoms under control, says Dr Cook, like eating well, moisturising, de-stressing with meditation, yoga and quitting smoking, for starters. (All of which is sound advice, we think youll agree.)

Though, as every case (and every body) is different, its best to consult a healthcare professional for the right treatment for you.

Chloe went 2 nights with only 4 hours sleep to see what effect sleep deprivation had on her body and mind.

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