Sun protection - sunburn

Make sure you never burn

Experts believe that sunburn during childhood can significantly increase your risk of malignant melanoma.

Why do we burn?

Our skin burns when we stay too long in the sun. Sunburn is our body's chemical response to over-exposure to UV rays.

Without protection, UV rays, which cannot be seen or felt on the skin, can penetrate deep into the skin's layers, damaging the cells. The radiation damages the material inside the nucleus of your cells that carries your genetic code, DNA.

Sunburn is not like a normal heat burn. When you get sunburnt the outermost layers of your skin release chemicals that cause your blood vessels to swell and leak fluids. This causes inflammation, pain and redness. Skin becomes hot and painful and severe sunburn can cause swelling and blisters.

Why does our skin peel?

Peeling after sunburn is your body's way of getting rid of damaged cells. This is necessary because cells damaged by the sun are at risk of becoming cancerous.

Although skin peels and new skin layers form, some sunburn damage may remain. This can cause problems later in life. So it is important to try to avoid burning in the first place.

How does the sun cause skin damage?

The sun emits UV rays which damage our skin. You can find out the strength of the sun's rays by looking at the UV Index.

There are two types of UV rays that damage our skin: UVA and UVB.

UVB radiation has a shorter wavelength than UVA. It penetrates the upper layer of the skin, the epidermis, and can cause sunburn and skin cancer.

UVA radiation has a longer wavelength and penetrates deeper into the dermis, affecting elastin and ageing the skin.

Until recently, UVA was thought not to have a role in skin cancer development. But increasing evidence shows that UVA and UVB both cause damage to DNA, which can lead to skin cancer.

It's easy to burn when you least expect it

Many cases of sunburn happen when people are not deliberately 'sunbathing'. You may be outdoors watching sport, doing the gardening or just sitting in the park.

We often forget how strong the sun can be. The sun does not need to feel hot to damage our skin. The heat in the sun comes from infra-red rays, not UV rays - so you can still burn on cool days. Your burn risk depends on your skin type.

Advice on treating sunburn is available on the NHS Direct website.

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