Sun and sunburn

Understanding sunlight and the skin

Too much exposure to sunlight is harmful and can damage the skin. Some of this damage is short-term (temporary), such as sunburn. However, allowing your skin to burn can lead to future problems, such as skin cancer.

There are two main types of damaging ultraviolet (UV) sunlight: UVA and UVB.

• UVA rays penetrate deeper into the skin, damaging the middle layer (the dermis). The dermis contains the elastic tissues that keep the skin stretchy. UVA rays therefore have the effect of ageing the skin and causing wrinkles.

• UVB rays are absorbed by the top layer of skin (the epidermis). This causes suntanning and sunburn.

Both UVA and UVB rays increase your risk of developing skin cancer, as does sunburn.

Melanin is the coloured pigment in our skins. When skin is exposed to sunlight, more melanin is produced to help protect the skin against the UV rays. This makes the skin darker - what people refer to as a suntan. Although melanin stops your skin burning so easily, it does not reduce the risk of developing skin cancer.

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Who is at risk from the sun?

Everyone is potentially at risk from excessive sun exposure. Children and babies are more at risk because their skin is so delicate, so they develop sun damage such as sunburn much sooner in the sun.

People most at risk of sunburn and skin cancer are those with fair skin, blue eyes, freckles, and red or fair hair. People with white skin have less melanin than those with darker skins, so are at more risk of burning. People with darker skin can still get sunburn but it may take longer in the sun.

Anyone in the sunshine can be at risk, for example, people who work outdoors, have outdoor hobbies or sunbathe. Sun damage is more likely when the sun's rays are at their strongest, for example, in countries close to the equator, at high altitude, or between 10 am and 3 pm.

Sun damage may also occur from exposure to other UV light sources such as sunbeds and sunlamps.

What is sunburn?

Sunburn is the most common problem caused by too much sun exposure to skin that has not been protected enough to prevent damage.

When white skin is sunburnt the skin becomes pink or red, hot and painful. The skin may blister. People with darker skins may not see a colour change, but their skin may feel hot after sun exposure. After a few days the sunburn may cause peeling skin.

How to treat sunburn

A cool shower or bath will help to soothe sunburnt skin. Soothing creams will help. After-sun lotions cool the skin and contain moisturisers (emollients) to counteract skin dryness and tightness. Paracetamol or ibuprofen will help with pain, if you are able to take them. You should see a doctor if the sunburn is severe. This may be if the sunburn covers a large area, has lots of blisters or if you feel unwell with sunburn.

You should never allow babies or young children to develop sunburn. If they do, you should seek medical advice the same day.

What other problems may be caused by too much sun?

Heat rash and prickly heat

These are skin rashes. For more information see the separate leaflet Heat rash and prickly heat.

Heat exhaustion

Heat exhaustion occurs when the temperature inside the body (the core temperature) rises to up to 40°C (104°F). A normal temperature is about 37°C (98.6°F).

At these temperatures, you may feel sick, have a headache, sweat excessively and feel faint. The body is losing water and becoming dehydrated.

The treatment for heat exhaustion is to move swiftly to a cool, shaded place, and to drink plenty of cool fluids. Recovery should happen quickly, usually within 30 minutes, and there are no long-term complications. If untreated, heat exhaustion can progress to heat stroke which is very serious. If you have heat exhaustion, or are looking after someone with heat exhaustion, and improvement is not occurring, it is important to seek urgent medical advice. For more information see the separate leaflet Heat exhaustion and heatstroke.

Heatstroke/sunstroke

Heatstroke occurs when the core body temperature rises above 40°C (104°F). It is very serious. The cells in the body begin to break down, important bodily functions stop working, internal organs can fail (such as the brain) and, in extreme cases, death can occur.

Symptoms include being sick (vomiting), confusion, fast shallow breathing (hyperventilation) and loss of consciousness.

Treatment for heatstroke in a hospital involves cooling the body to lower the core temperature, and using an intravenous drip to replace the fluids lost.

See also the separate leaflet called Heat exhaustion and heatstroke.

What are the effects of long-term sun damage?

Skin damage

The effects of repeated sun damage include premature skin ageing and wrinkling, brown spots, non-cancerous (benign) warty growths on the skin (actinic keratoses), and skin cancer.

Skin cancer

About 8 to 9 of every 10 skin cancers are thought to be caused by sun damage. See the separate leaflets called Non-melanoma skin cancer and Melanoma skin cancer for more information. In particular, sunburn greatly increases the risk, particularly sunburn in childhood. Skin cells that are sun damaged are at greater risk of becoming abnormal and cancerous.

How can I avoid getting sunburnt?

In short: avoid the sun when it is strong, cover up with suitable clothing and use high-factor sunscreen.

Avoid the sun as much as possible when the sun is strong

In the UK, avoid direct sun exposure between 11 am and 3 pm between March to September. This applies all year round in hotter countries nearer to the equator. This middle time of the day is when the sun's rays are the strongest. Trees, umbrellas and canopies or suitable clothing can all provide good shade.

Cover up

Cover up when you are in the sunshine:

• Wear wide-brimmed hats with a brim that goes all around the hat to protect the face and neck. These are the areas most commonly result in sunburned skin. Men, in particular, seem most likely to develop skin cancers on their necks, shoulders and backs (women tend to get skin cancers more on their legs and arms). Baseball caps are not as effective, as they shade the face but not the neck, lower face and ears (unless you buy one with a neck protector). Young children should wear hats with neck protectors.

• Wear loose baggy T-shirts (or even better - long-sleeved tops) and baggy shorts. The material should be tightly woven to not allow sunlight through.

• Wear wrap-around sunglasses (your eyes can get sun damage too). Make sure the sunglasses conform to the European Standard, indicated by the CE mark (or equivalent) and are labelled as providing protection against UV light.

Use high-factor sunscreen liberally

You should apply sunscreen of at least sun protection factor (SPF) 30 (SPF 50 for children).

SPF gives a guide to how much sun protection is afforded by a particular sunscreen. The higher the SPF, the greater the protection. The SPF label shows the protection against UVB which can cause sunburn and increase the risk of skin cancer.

It is also important that your high SPF sunscreen has a high level of UVA protection. UVA can cause ageing effects of the skin and also, potentially, the damage that can cause skin cancer. Sunscreens with high UVA protection will have a high number of stars (these range from 0 to 5). It is advised to use a sunscreen which has at least 4 stars.

Be sure to cover areas which are sometimes missed, such as the lips, ears, around the eyes, neck, scalp (particularly if you are bald or have thinning hair), backs of hands and tops of feet.

Sunscreen is not an alternative to avoiding the sun or covering up. It is used in addition.

Ideally:

• Apply sunscreen 20-30 minutes before going out into the sun (it takes a short time to soak into the skin and to work).

• Re-apply frequently, at least every two hours, and always after swimming, towelling yourself dry or excessive sweating (even those that are labelled water-resistant).

• Apply enough sunscreen to cover exposed skin. For most people this is the equivalent of two teaspoons of cream for the head, neck and arms. For the whole body while wearing a swimming suit, this would be around two tablespoons.

• Re-apply to children even more often.

Sunblock is different to sunscreen. Sunblock is opaque and stronger than sunscreen. It is able to block most UVA and UVB rays, owing to the ingredients it contains (usually titanium dioxide or zinc oxide). As with sunscreen, sunblock is to be used in addition to other ways to protect your skin against sun damage.

Children and babies

Babies under 6 months of age should not be exposed to direct sunlight between the months of March to October in the UK. They should be kept in the shade or their skin covered by suitable clothing. Babies and children over 6 months of age should follow the cover up and avoiding strong sunshine advice above, as well as using SPF50 sunscreen. This should be applied more often to children than adults. Babies and children are at higher risk of heat exhaustion and heat stroke than adults, as they are less able to regulate their body temperature. Babies and children should never get sunburn. If they do, seek urgent medical attention.

More tips for protecting skin from sun damage

• Sunscreens can go off and not work after a time. Therefore, do not use out-of-date sunscreen (see the use by date on the bottle). Most have a shelf-life of 2-3 years.

• Being kept in the sun can cause deterioration of the active protective ingredients in sunscreen. Be wary of buying bottles of sunscreen that have been kept on a shelf in direct sunlight or outside in hot countries. Try to keep your sunscreen somewhere cool and shaded.

• Some experts think that the increased use of sunscreen lotions and creams may give a false sense of security. This may encourage people to go into the sun more and, as a result, cause an increase in your risk of developing skin cancers. It has to be emphasised that sunscreen only partially protects your skin. Using sunscreen does not mean that you can sunbathe for long periods without harm. If you tan then you have done some damage to your skin.

• Reflected light causes sun damage. On sunny days, even if you are in the shade, sun can reflect on to your skin. Sand, water, concrete, snow and ice can all reflect light and cause sun damage.

• Wet clothes let through more UV light than dry clothes. Take spare clothes with you if you expect to get wet.

• You can burn in the water. Even if you are swimming in a pool or snorkelling in the sea, you can still get burnt.

• Clouds may give a false sense of security. Most of the UV radiation from sunshine still comes through thin cloud cover.

• Many clothes worn in hot weather allow a lot of sunlight through. You need to wear tightly woven clothes to protect from the sun's rays. If you can see light through a fabric then damaging UV rays can get through too. Some clothing states it provides sun protection such as SPF50 clothing.

• The sun's rays are more powerful at higher altitudes. It may be cooler up a mountain but you will need more skin protection.

• Fair-skinned people who sunburn easily are at particularly high risk sun damage and should be most careful about protecting their skin.

• There is no such thing as a healthy tan. A tan is the skin's response to the sun's damaging rays and is therefore an indicator of sun damage.

• Artificial tanning from sun-ray lamps and tanning beds is just as damaging as sunshine - the advice is to avoid them. Studies have shown that sunbed use can make you much more likely to get all types of skin cancer.

• Fake tan from a bottle is safer than a natural tan because no sun exposure is required. Remember that fake tan is not a sunscreen, and, if you plan to go out in the sun, you will need to apply another product. Some fake tans are bronzers that simply stain the skin and can be washed off. Other products contain a chemical that reacts with the skin to give a tanned colour. The long-term effects of these chemicals are not yet known. However, they seem to be safer than tanning in the sun or under a sunbed.

• It is not the heat that does the damage but the UV radiation in sunlight, which is present all year. You can get a lot of exposure to UV doing winter sports, such as skiing, as it is often done in sunny weather and at high altitudes. In particular, remember ice and snow reflect a lot of sunlight. So, you should wear a hat, sunscreen, lip balm containing an SPF, and sunglasses.

The Solar UV Index

The Met Office provides information called the Solar UV Index with their weather forecasts. The index is given as a figure in a triangle over the maps they use when giving forecasts. Basically, the higher the index (from 1 to 10), the greater the risk from the sun, and the more care you should take of your skin when outside.

Sun protection is advised when the UV index is forecast to be 3 or higher.

Benefits of sunshine

Vitamin D

Vitamin D is vital for good health. Vitamin D is made in the skin with the help of sunlight. Sunlight is the main source of vitamin D for the body, as there is not enough found in the foods that we eat.

People need vitamin D for bone health as well as our body functions. Children with severe vitamin D deficiency may develop a condition known as rickets. Adults with severe vitamin D deficiency may develop a condition known as osteomalacia.

This means that to be healthy you do need a certain amount of sun exposure. Avoiding the sun altogether can cause vitamin D deficiency. The aim is to enjoy the sun sensibly, so as to make enough vitamin D, whilst not increasing the risk of skin cancer.

It is estimated that, to prevent deficiency of vitamin D in the UK, we need 2-3 sun exposures per week between March to September. Each exposure should last 20-30 minutes and be to bare arms and face. Short frequent periods of time in the sun are much more beneficial than long periods of time. It needs to be exposure to direct sunlight and not through a window. It is not the same as suntanning, and sunburn should be avoided at all costs. Darker skinned people may need more sun exposure to prevent vitamin D deficiency.

Everyone in the UK should consider taking a supplement of 10 micrograms of vitamin D through the winter. Other groups of people are advised to take vitamin D all year round. See the separate leaflet Vitamin D deficiency for more information.

Increased wellbeing

Sunlight tends to improve our general well-being and make us happier. It does this by causing us to produce more of a 'happy hormone' called serotonin. Physical activities and exercise outdoors are good for us, and we need to balance this against avoiding sun damage. The way to balance the good and bad effects of the sun is to enjoy the sun safely. This means using all the tips above.

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