How the sun damages your skin: UV exposure and skin cancer

The sun is an essential part of life, providing warmth and aiding in vitamin D production. However, the effects of sun damage can be long-lasting and, in some cases, life-threatening.

In this article, leading dermatologist Dr Saqib Jawaid Bashir explores how UV radiation harms the skin and what steps you can take to protect yourself.

How UV radiation affects the skin

The sun emits different types of ultraviolet (UV) radiation, but the two that impact the skin the most are:

UVA rays: they penetrate deep into the skin, leading to premature ageing and long-term cellular damage.
UVB rays: they affect the skin’s outer layers and are responsible for sunburn. They are also a primary cause of DNA mutations that can lead to skin cancer.

Both types contribute to skin cell damage, increasing the risk of skin cancer over time.

How does sun exposure cause skin cancer?

Sunburn is a visible sign of skin damage, but even without visible redness, harm occurs at a cellular level.

Repeated sunburns directly damage the DNA within skin cells. When this DNA is damaged, the body's natural repair mechanisms may not always function correctly, leading to mutations.

Over time, these mutations can result in uncontrolled cell growth, which is how skin cancer develops.

Types of skin cancer

There are three main types of skin cancer, all linked to UV exposure:

Basal Cell Carcinoma (BCC): the most common type, often appearing as a shiny bump or scaly patch. It grows slowly, but it can cause significant local damage if left untreated.
Squamous Cell Carcinoma (SCC): it can appear as a red scaly sore that doesn’t heal. It is more aggressive than BCC and has the potential to spread.
Melanoma: the most serious form of skin cancer. It can develop from existing moles or appear as new, irregularly shaped dark patches. Melanoma spreads quickly if not detected early.

Who is most at risk?

Anyone can develop skin cancer, but certain factors increase the risk, including:

Fair skin: people with lighter skin have less melanin, making them more vulnerable to UV damage.
The use of sunbeds: sunbeds expose the skin to concentrated UVA and UVB radiation, significantly increasing the risk of skin cancer.
Frequent sun exposure: spending long hours in the sun without adequate protection increases the risk of UV-related skin damage.
History of sunburn: repeated sunburns increase the likelihood of developing skin cancer later in life.
Family history: a genetic predisposition can make some individuals more susceptible.

How to protect your skin from sun damage

The following steps are essential to minimise the risk of sun damage:

Use sunscreen properly

Applying sunscreen is one of the most effective ways to protect your skin. Choose a broad-spectrum sunscreen with SPF 30 or higher and reapply every two hours, especially if swimming or sweating.

Seek shade and wear protective clothing

UV rays are strongest between 11 am and 3 pm, avoid direct sun exposure during these hours. Wearing long sleeves, sunglasses, and a wide-brimmed hat can provide additional protection.

Check your skin

Regularly examine your skin for any changes in moles, new growths, or unusual patches. If you notice anything suspicious, like sores that do not heal, consult a dermatologist as soon as possible.

While the sun has its benefits, overexposure can have dangerous consequences. UV radiation is a leading cause of skin cancer, but taking simple precautions, can greatly reduce your risk.

If you are concerned about skin damage or have noticed any unusual changes, consult with Dr Saqib Jawaid Bashir via his Top Doctors profile to assess your condition and explore the best course of action.