Can Sunburn or a Tanning Bed Really Treat Acne?

Social media is awash with dubious advice, and one of the latest skincare ‘hacks’ being promoted online is particularly concerning.

Some TikTok creators claim that getting sunburnt or using a tanning bed can clear acne.

Although natural sunlight and UV radiation have long been used in treatments for certain skin conditions, evidence indicates that these approaches do not work for acne. Any apparent improvement in the skin’s appearance is also outweighed by the serious risks associated with excessive UV exposure.

UV exposure and acne

Phototherapy is a medical treatment in which skin is exposed to sunlight or UV radiation under controlled conditions. It is commonly used for psoriasis and eczema when other treatments have failed or are unsuitable for a patient.

Research suggests that phototherapy can lower inflammation and dampen the skin’s immune response, both of which are important in the development of these conditions.

However, this treatment is carried out clinically, with the radiation dose carefully regulated to limit the harmful effects of UV exposure. Tests before treatment are also undertaken to minimise the chance of burning.

For acne, though, there is little evidence that exposure to UV radiation provides a benefit.

A 2023 retrospective cohort study involving 19,939 participants examined the six years of UV exposure before they enrolled. It found that young adults with long-term daily exposure to comparatively low levels of UVB - an invisible form of radiation emitted by the sun - for around one hour were associated with a lower risk of moderate to severe acne.

Yet the study had substantial limitations. The exact UV doses received by participants were not measured directly. Instead, researchers estimated sunlight exposure using location and weather data. The study also did not account for the harmful consequences of exposure.

Research using human skin cells has identified some possible effects of UVB rays, including the destruction of Propionibacterium acnes, the bacterium believed to cause acne. However, these effects have been demonstrated only in cells, not replicated in studies involving people. Most such studies also concluded that any positive effect was likely to be small and inadequate for treatment, particularly in view of UV radiation’s harmful side-effects.

A 2023 narrative review covering studies of sun exposure and acne published between 1992 and 2022 concluded that UV radiation exposure is unlikely to improve acne symptoms.

In certain cases, it could even make acne worse. UVB radiation may activate immune cells that intensify acne-related inflammation and raise sebum production, a recognised acne risk factor.

Sunburn risks

There is not only a lack of evidence that sun exposure can treat acne; sunlight also has many well-established harms, including a greatly increased risk of skin cancer.

Studies indicate that just one blistering sunburn during childhood or adolescence can double the likelihood of developing skin cancer later in life. The more frequently a person is sunburnt, the greater their skin cancer risk becomes. This is because UV exposure inflicts considerable DNA damage on skin cells.

UV radiation also plays a major role in premature skin ageing. It damages collagen and elastin, which may cause the skin to sag and wrinkles to develop.

When spending time in the sun, it is important to:

1. Apply broad-spectrum sunscreen with at least SPF 30, reapplying it every two hours and after swimming or sweating.
2. Stay in the shade, particularly during peak sunshine hours, typically 10am to 4pm.
3. Wear protective clothing, including wide-brimmed hats and UV-blocking sunglasses.

Effective acne treatments and sun safety

Currently, the most effective treatments for acne are available either from a pharmacy or on prescription from a doctor.

Severe acne may be treated with oral antibiotics, which have an anti-inflammatory effect. A doctor may also prescribe isotretinoin, a synthetic derivative of vitamin A. It decreases skin oils (sebum), skin bumps and the quantity of acne-causing bacteria in the skin. Isotretinoin is very effective at clearing acne lesions, by 85 percent in one study after four months of use. Only around one-quarter of patients who take it need a second treatment course.

Although these treatments work, worries about drug side-effects - particularly mood changes - may explain why some people with acne seek alternative options.

However, a recent study of more than 30,000 isotretinoin patients found no link between isotretinoin and mood changes, indicating that this side-effect is extremely uncommon.

Anyone prescribed acne medication should take extra care in the sun. Isotretinoin and tetracyclines, a group of antibiotics, can act as photosensitisers, meaning that sun exposure can cause greater skin damage. One study found that 20-40 percent of acne patients taking a common form of tetracycline experienced photosensitivity.

This is why sunscreen is important when going outdoors on sunny days. As well as protecting the skin and reducing the risk of skin cancer, evidence suggests sunscreen may help people with acne by lowering inflammation in skin cells and reducing photosensitivity.

Several safe, effective acne treatments already exist. If you are considering the sun or a tanning bed because your current treatment does not seem to be working, speak to your doctor rather than risking complications.

Karl Lawrence, Research fellow, King's College London and Wisam Alwan, Clinical Research Fellow in Dermatology at King's College London/Consultant Dermatologist Guy's and St. Thomas' NHS Foundation Trust, King's College London

This article is republished from The Conversation under a Creative Commons licence. Read the original article.