Psoriasis is a common skin condition that can occur at any age and affects both males and females equally. It often runs in families and is thought to have a genetic basis. The disease itself is caused by a change in skin cell turnover. It’s not contagious and cannot be transferred from one part of the body to another.

Normally skin cells take about 3-4 weeks to replace themselves, but in psoriasis, this process is greatly accelerated, and skin cells can be replaced every 2-6 days. This quicker process means that skin cells don’t have time to mature properly so they get to the surface and they’re not yet ready to be shed. This results in an accumulation of cells on the surface, which form a psoriatic plaque. The plaques appear as raised red patches of skin, covered with silvery-white scales. The silvery-white scales are the accumulation of the skin cells waiting to be shed, and the redness is due to the increase in blood vessels required to support the increase in cell production.

The condition can range in appearance from mild to severe. The plaques can appear in a variety of shapes and sizes, varying from a few millimetres to several centimetres in diameter, but they all have a well-defined border from the surrounding skin. It also common for the complaint to be itchy, and it can sometimes feel painful or sore.

Most people with psoriasis have the Vulgaris form in which larger plaques tend to appear on areas such as the elbows, knees, lower back and scalp. In guttate psoriasis, patches are usually smaller (often less than 1cm in diameter) and cover many areas of the body. This form is most often seen in children and teenagers and can be triggered by a throat infection. Other forms of psoriasis include pustular psoriasis, which is characterised by small blisters on the hands and feet, and nail psoriasis where there are changes in the appearance and texture of the nails, such as the development of ridges and pitting. In some cases, psoriasis can also cause joint problems that resemble rheumatoid arthritis.

In the past, psoriasis was thought to be a condition that existed purely within the skin. It is now understood that it is actually changed within the immune system that triggers the condition.

Psoriasis is frequently referred to as an ‘autoimmune’ or ‘T-cell mediated disease’. T-cells are a type of immune. They naturally circulate throughout the body waiting for other types of immune cells to alert them to a foreign substance. These foreign substances, called antigens, activate the T cell, which then initiates an immune response. The problem in psoriasis is that the T-cells end up in the skin and become overactive, producing excessive amounts of inflammatory chemicals and growth factors that can initiate the formation of a psoriatic plaque.

The cause of this overactivity is thought to be genetic but there are also links to digestive imbalances, stress and diet.

Medically psoriasis is usually initially treated with emollient and steroid creams. There are also drugs available that work on the turnover of skin cells that can be used for more severe cases. Sometimes UV light therapy is used either alone or in combination with medications to slow down skin cell turnover.

A functional medicine approach to psoriasis looks at how digestive function, diet and stress are influencing the immune system and aims to address the root causes. For example:

• Increased intestinal permeability and abnormalities in the lining of the gut have both been demonstrated in psoriasis patients. If the gut lining becomes leaky, the passage of antigens into the bloodstream increases, creating a situation called autointoxication. The immune system then reacts to the antigens, producing inflammation. In psoriasis, the deposit of excess antigens in the skin is thought to be one possible trigger for the development of a plaque.
• When protein digestion is poor, gut bacteria can start to break down the undigested proteins and produce toxic substances. One group of toxins are polyamines, which have been found to be higher in people with psoriasis than in the average population. Polyamines blocking the production of a substance that helps to stop skin cells going into division overdrive. Since protein digestion occurs in the stomach and the small intestine, low levels of stomach acid or reduced digestive enzymes levels may be to blame.
• Imbalances in friendly bacteria levels, as well as overgrowth of bad bacteria or yeast, can also exacerbate psoriasis. This is because gut flora imbalances can lead to excess toxin production in the intestines as well as interfering with the processes that keep the gut lining healthy.
• Leaky gut, gut flora imbalances and problems with digestive function can be identified by a comprehensive functional stool analysis and then targeted with a specific rebalancing protocol.
• Food sensitivities can also be an underlying cause in psoriasis, compromising gut integrity and triggering inflammation. A functional medicine practitioner will be able to identify those foods that are worsening your symptoms and design you a personalised low-reactive diet.

It is widely accepted that stress has an impact on psoriasis and the condition often worsens during stressful life periods. When people with psoriasis are put under stressful conditions their immune system actually starts to make more T-cells ready to create an inflammatory response that could lead to a flare-up. Stress can also compromise digestion. If stress is a trigger factor for your psoriasis, a functional medicine practitioner can also give you advice on natural stress management to allow you more control over your symptoms.