5 minute

Psoriasis: Understanding and Addressing the Underlying Causes

Kim Haslam
Kim Haslam
Written on
August 31, 2022

Psoriasis: Understanding And Addressing The Underlying Causes

Psoriasis is a common immune-mediated skin disorder that affects approximately 1 - 4 % of the global population. It is characterised by salmon-pink scaly or red plaques, most commonly located on the elbows, knees, intergluteal cleft, nails and scalp. Psoriasis has been traditionally understood as a chronic, multifactorial, immune-mediated inflammatory skin disease, but within the last decade, it has also been recognised as a systemic inflammatory disorder affecting the whole body.

There are 5 types of psoriasis, including guttate, pustular, plaque, inverse and erthyrodermic psoriasis, with plaque type being the most common. Normally, our skin cells take about three to four weeks to replace themselves. This process is accelerated in psoriasis, with skin cells being replaced every two to six days. This means that skin cells don't have time to mature properly, resulting in an accumulation of cells on the surface, which form psoriatic plaques. This process is mediated by immune system activity.


Whilst conventional medicine tends to view psoriasis primarily as a skin condition, psoriasis is essentially an autoimmune condition. Autoimmunity can generally be understood as the result of a genetic predisposition, and an environmental trigger combined with impaired gut health, and in the case of psoriasis, it is no different. Although the pathogenesis of psoriasis is not entirely understood, recent research shows an association between increased intestinal permeability, abnormalities in the lining of the gut and psoriasis.

Psoriasis patients seem to have an increased risk for other autoimmune disorders, particularly vitiligo, diabetes mellitus, autoimmune thyroiditis, rheumatoid arthritis, and IBD. We are increasingly aware that if someone has an autoimmune condition they are at risk of developing others, and Psoriasis follows that pattern.

Underlying Causes of Psoriasis

The underlying causes of psoriasis vary from person to person, but some of the common causes can include:

Poor Digestion
Poor digestion, especially incomplete protein digestion, can lead to the creation of toxins known as polyamines, which contribute to the excessive skin proliferation that drives psoriatic plaques. Low levels of stomach acid and/or reduced digestive enzyme levels may be at the root of this pathology.

Increased Intestinal Permeability ("Leaky Gut!)
Both increased intestinal permeability and abnormalities in the lining of the gut have been observed in psoriasis patients. The loss of barrier function allows the translocation of bacterial antigens into systemic circulation, where they may contribute to immune activation and act as a trigger for plaque formation. Research also indicates a higher level of circulating lipopolysaccharide (LPS) - the endotoxin derived from gram-negative bacterial cell walls. LPS is strongly pro-inflammatory, indicating a need for both intestinal barrier support and anti- inflammatory interventions.

Microbiome Imbalances
Over the past decade, the association between the microbiome and inflammatory skin diseases has been increasingly recognised. It is observed that imbalances in gut bacteria, or an overgrowth of Candida albicans can worsen existing psoriasis. An assessment of gut flora balance, candida and digestive function may be useful - see below for more on testing.

Nutritional Deficiencies
Psoriasis is associated with nutritional deficiencies, in particular omega 3 (n-3) fatty acids and vitamin D. Emphasising n-3 polyunsaturated fatty acids, vitamin D, vitamin B12, short chain fatty acids, selenium, and dietary fibre may mediate psoriasis via the suppression of inflammatory pathways.

Food Sensitivities
Some evidence suggests that food sensitivities may play a role in psoriasis. Gluten is a potential trigger for those who are sensitive, and research suggests a potential link between Coeliac disease and psoriasis. Other possible culprits may be nightshades and alcohol. Ultimately, food sensitivities may be compromising gut barrier function and triggering inflammation, and so a careful exploration of potential triggers may be useful.

Other factors that can contribute to flare ups are stress, alcohol intake, skin injuries including sunburn, changes in temperature, and anything else that affects the immune system including other illnesses such as respiratory infections and ear infections.


Psoriasis is usually diagnosed by a skin examination, with a biopsies sometimes used for confirmation. There is no single blood test that can diagnose the condition. With a psoriasis diagnosis, the patient is at a higher risk for certain comorbidities including other autoimmune diseases such as systemic lupus erythematosus, autoimmune thyroid disease, celiac disease, inflammatory bowel disease (IBD), especially Crohn's disease, multiple sclerosis, Sjögren's syndrome, vitiligo, and alopecia areata. Additional autoimmune tendencies can therefore be tested for. Colabs’ AL314 Auto-immune Panel includes antinucelar antibodies, rheumatoid Factors, anti-CCP, anti-dsDNA and thyroid antibodies.

Potential nutritional deficiencies that may be contributing to psoriasis can be easily identified with our Nutrient Testing. We offer an Essential Elements Panel, Mineral Panel, Omega Check, Amino Acids Panel and Fructose Examination. Different panels can be combined for a more complete picture. Food sensitivities can be investigated with a careful elimination diet.

The GI Map will give both an indication of upper digestion secretions with markers such as pancreatic elastase and steatocrit informing as to enzyme function and fat malabsorption. As well as offering a comprehensive view of the microbiome, The GI Map also includes some key bacteria that have the potential to trigger autoimmunity including Citrobacter freundii, Klebsiella pneumoniae and Klebsiella pneumoniae. Immune response and inflammation markers are also included, with an option for Zonulin as an add-on.

Our Intestinal Permeability and Barrier Analysis has analytes including leaky gut markers such as zonulin, B-Defensin, LPS and IL6, as well as calprotectin, histamine, DAO and food intolerance markers. It also offers an indication of immune defence, detoxification capacity and regulation of inflammatory processes.

Inflammatory markers such as ESR, CRP, Rheumatoid Factor and anti-CCPs can be added to any Colabs panels. If you'd like more information on any of the above tests, please do drop us an email.