Tassneem Miah
Communications Lead, The Psoriasis Association
Sun safety is crucial for those with psoriasis. Explore sun safety tips and learn about hospital UV treatment for this condition affecting 2–3% of the UK population.
In the UK, psoriasis affects around 1 in 50 people. It can develop at any age, with early adulthood or between 50 and 60 being common.
What is psoriasis?
Psoriasis is an immune-mediated inflammatory disease characterised by raised, flaky skin patches known as plaques. Typically, the skin cell replacement process takes around 21–28 days; for people with psoriasis, this is accelerated to only a few days.
Types of psoriasis
Plaque psoriasis affects roughly 80% of individuals and presents as raised, dry skin patches covered in grey or silver scales. Its appearance varies based on skin tone; in fair skin, it may appear as pink or red patches with silvery-white scales. In darker skin, it manifests as purple or brown patches with grey scales. Other types include guttate psoriasis, as well as rarer, severe forms like generalised pustular psoriasis (GPP) and erythrodermic psoriasis.
Natural sunlight and psoriasis
For many people with psoriasis, sunshine can help improve the skin’s appearance. Sunlight emits ultraviolet (UV) light, consisting of UVA and UVB rays; UVB penetrates the skin and slows the growth rate of skin cells affected by psoriasis. UVB also helps your body produce vitamin D, which contributes to healthy skin and bones.
Exposure to UV light (A or B) can increase
the risk of premature ageing, skin
damage, sunburn and skin cancer.
Sunbeds and hospital UV treatment
Hospital UV treatment is very carefully controlled; a dermatologist will administer the right amount of exposure and monitor the results. Hospital-based UV treatment uses only the specific part of the spectrum, which treats skin conditions and is well-monitored.
It includes two main types: Narrowband UVB (administered in a hospital phototherapy unit) and PUVA treatment (combines UVA light with psoralen, effective for thicker plaques). Sunbeds emit UVA light, which is ineffective for psoriasis treatment without psoralen.
Associated risks with artificial and natural sun exposure
Exposure to UV light (A or B) can increase the risk of premature ageing, skin damage, sunburn and skin cancer. Sunburn can also trigger ‘Koebnerization,’ where psoriasis appears on areas of skin injury.
While sunlight can benefit psoriasis, sun safety is crucial, particularly as treatments like topical treatments (applied directly to the skin), systemics (affect the entire body) and biologics (target specific parts of the immune system) can increase the skin’s sensitivity to sun.
The NHS advises wearing high-SPF sunscreen and reapplying regularly. Avoiding peak sunlight hours, wearing protective clothing like hats and sunglasses and opting for loose-fitting, pale clothing are additional precautionary measures.
