Psoriasis - skin condition

What is Psoriasis?

Psoriasis ("psora"=itch, "sis"=state) is a skin condition affecting around 2-3% of the population in the UK. This disease is virtually absent in some populations such as South American Indians and Australian Aborigines. It is autoimmune in nature, meaning that elements of the body's immune system attack the skin, causing the signs and symptoms of the disease. It is also generally remitting/relapsing in nature, being worse during some periods than at others. Being autoimmune in nature it is not possible to pass it on to other people.

There are different types of this disease, the most common form being plaque psoriasis (psoriasis vulgaris), which affects up to 90% of people with psoriasis. In this form, the disease causes excessive proliferation of the keratinocytes on the surface of the skin. This creates silver white scaly patches on the skin called plaque. It typically affects the knees, elbows, scalp and back. It is seen as an incurable disease, as is true of many autoimmune conditions. However, by addressing other issues that affect the whole of the body, such as stress and digestive imbalances much can be done to reduce its impact.

Inverse psoriasis affects around 5% of those with psoriasis, so roughly 1 in 1,000. Skin inflammation occurs between the thighs and genitals and under the armpits.

Guttate psoriasis affects around 2% of those with psoriasis, so roughly 1 in 2,500 people. It occurs most often after a streptococcal infection. Most people will completely recover from this form of the disease, although up to 40% may go on to develop standard psoriasis. 

Psoriatic arthritis can be a complication in about 1/4 of all common psoriasis cases.

Symptoms

Plaque psoriasis features patches of raised, red skin at sites such as the knees, elbows and scalp. It is by far the most common type.

Inverse psoriasis presents with flat lesions of red, moist, smooth and shiny skin in areas where skin touches skin. Areas such as the armpits, groin and under breasts are affected. Irritation and itching are common.

Guttate psoriasis features teardrop like spots, typically on the trunk. It may spread to the arms and legs and occasionally the face, ears and scalp. 

Causes

Nutrient deficiency/excess

This is a common cause for psoriasis.

Vitamin D

A key nutrient is vitamin D which is best received from direct sunlight. A UVB lamp is a good altenative in winter months with oily fish, liver and dairy produce as less powerful dietary sources of vitamin D.

Collagen

Collagen is a key component of skin and increased levels of it can help the skin to repair itself in cases of psoriasis. Eating bone broth and other less popular cuts of meat containing gelatine, which is derived from collagen, can help here.

Balance of polyunsaturated fats

Nuts and seeds or foods prepared in their oils, contain loads of omega 6 fatty acids. These can promote inflammation, which is fine in moderation, but too much is a bad thing and can worsen psoriasis symptoms. Equally foods containing omega 3 fatty acids such as oily fish can improve symptoms.

Gut problems

Problems in the gut can lead to psoriasis with both leaky guts and dysbiosis being responsible. Leaky guts allow large particles to travel from the digestive tract directly into the bloodstream. There they cause an immune response that can target skin cells, leading to inflammation. Dysbiosis is a state in which unhealthy bacteria predominate in our intestines. This also changes the types of cell our immune system releases, leading to inflammation around the body, which in some people is focused on their skin.

Stress

Stress can release chemicals in the skin, which can then affect the lining of blood vessels and immune cell levels. The blood vessels may contract limiting blood flow and making hands and feet colder, while extra immune cells causes inflammation under the skin.

Conventional treatment

The common plaque type of psoriasis is typically treated using a variety of creams. A cream needs to be carefully applied for a period of many weeks before a plaque clears. More severe cases may be treated with light therapy (see diet and lifestyle below) or drugs.

Moisturisers

These can be used to soften and loosen flaky skin. They may reduce itching and cracking of the skin.

Coal tar preparations

Coal tar

Coal tar creams been used for a long time. They may reduce inflammation, proliferation of skin cells and have anti-flaking effects. They can lead to skin discolouration. Unless you use a mild coal tar cream don't use them in flexures of skin, such as elbows, armpits and the groin, where skin touches skin. Also avoid during the first 3 months of pregnancy.

There is some evidence that coal tar preparations can be as effective over the longer term, as combinations of vitamin D creams with steroids(7).

Dithranol

This is a derivative of coal tar that produces a white paste. It has been available for a long time and like coal tar it can stop skin cells proliferating and has anti-inflammatory effects.

Steroid creams

While these may reduce inflammation and some of the symptoms, they can lead to worse symptoms when you stop using them. Steroid creams used long term may also thin the skin and discolour it.

Diet and lifestyle

There is quite a lot that can be achieved for psoriasis by changing diet. This can be 

Gut health and inflammation

Eating foods that reduce inflammation in the gut makes a lot of sense for anyone with psoriasis. As with virtually all autoimmune conditions psoriasis symptoms improve when anti-inflammatory foods are included in place of inflammatory foods.

Foods to decrease

Inflammatory foods include nuts, seeds, grains and their oils, which contain a lot of the inflammatory omega 6 oil , linoleic acid. 

Foods to increase

Anti inflammatory oils from oily fish such as trout, salmon, sardine sand anchovies can all help reduce psoriasis symptoms. Algae is a vegetarian alternative.

Vitamin D

The use of UVB lamps has proven effective in a number of cases. This may be due to to the fact that it raises levels of vitamin D. Vitamin D has the capacity to damp down the cell proliferation that causes psoriasis in the first place. So exposure to UVB lamps or getting out should have a beneficial effect(8).

Vitamin A

Tazarotene

Tazarotene is based on vitamin A and has been used to successfully treat psoriasis

Aloe Vera

Aloe Vera cream may be as effective as steroid creams, and should avoid some of the side effects of steroids, namely thinning of the bones and the skin(9).

References

6) http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4055457/ omega 3 oils

7) http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4248495/ coal tar + salicylic acid vs vitamin D + steroid

8) http://archderm.jamanetwork.com/article.aspx?articleid=210090 The use of UVB light

9) http://www.everydayhealth.com/columns/zimney-health-and-medical-news-you...