Skin Damage Caused by Sunlight

Some sunlight is important because our skin uses it to produce vitamin D, which helps to build and maintain strong bones. Too much sun is harmful and can damage your skin.

The sun gives out ultraviolet (UV) radiation that is made up of three types of rays: UVA, UVB and UVC. UVC rays from the sun can’t get through the ozone layer but UVA and UVB rays can, and these rays have been linked to skin damage.

Short-term skin damage

Sun tan

A tan is actually a sign that your skin has been damaged and is trying to protect itself. UV radiation stimulates your skin to produce more pigment (colour), which protects against damage. Your tan will fade, but the damage to your skin remains.

Sunburn

Short-term overexposure to the sun can cause your skin to burn, usually making it red, hot and painful. You can soothe your burnt skin with calamine lotion or aftersun lotions. If your sunburn is severe, you may need medical treatment.

Heat exhaustion and heat stroke

This is when your body becomes overheated after overexposure to the sun or by getting sunburn. You may have symptoms including vomiting, headaches and fever. If you think you have heat stroke, get to a cool place as soon as possible and drink plenty of water. If your temperature is higher than 39ºC (you can measure your temperature using an oral thermometer), your skin has become dry and flushed or you feel very unwell, you should see a doctor immediately.

Long-term skin damage

Ageing and infection

Ageing of your skin is a result of the UVA rays penetrating it, causing wrinkles and sagging. UV rays can also cause damage to the eyes. It has been suggested that too much sun exposure may damage your immune system, increasing your risk of infection.
Skin cancer

Although the exact cause of skin cancer isn’t known, some things make it more likely. Your risk of skin cancer increases if you’re exposed to UV rays because of spending a lot of time in the sun.

Preventing sun damage

To protect your skin, you should stay out of the sun between 11am and 3pm, when the sun’s UV rays are strongest. Look for shady areas such as under trees, and use umbrellas or canopies.

Watch the UV index

The UV index describes the strength of the sun’s UV radiation. It’s usually shown as a number in a triangle on a weather map. The numbers range from one to 11+ and the higher the number, the stronger the UV radiation. If the UV index is higher than three you will need protection when you go outside.

In many countries, the UV index is reported alongside the weather forecast in newspapers, on TV and on the radio.
You can protect your skin by wearing long-sleeved tops and trousers. Choose materials that have a close weave as these block out the most UV rays. Wet clothing stretches and lets more UV radiation through to your skin.

Wearing a wide-brimmed hat can halve the amount of UV radiation reaching your face.

Sunglasses help to protect your eyes and eyelids. Wraparound sunglasses will also protect the skin around your eyes. You should choose a pair of sunglasses that has the following labels:

* 100 percent UV protection
* UV 400 – this means it protects from both UVA and UVB rays

If you’re buying a pair of sunglasses in Europe, check that they also carry the European Standard CE mark and the British Standard (BE EN 1836:1997).

Wear sunscreen

Always use “broad spectrum” sunscreen. This means that it protects your skin against UVA and UVB rays. Make sure it has a sun protection factor (SPF) of 15 or higher. The SPF tells you how good the sunscreen is at filtering out the UVB rays. There isn’t a measure of protection against UVA rays. Sunscreen can’t give you complete protection since some UV rays will always get through, but you will get more than 90 percent protection from UVB rays with SPF 15.

Re-apply sunscreen every two hours or more often if you go swimming, or sweat a lot. Water reflects the sun’s rays so you need to apply sunscreen before swimming.

Cloud doesn’t stop the sun’s UV rays getting through so you should protect yourself even if it’s cloudy. Haze (from thin clouds or mist) can even increase your UV radiation exposure because the rays are scattered.

Check moles

You should check your moles regularly for changes that may indicate skin cancer. Most changes are harmless, but you should see your GP if you notice:

* growth of an existing mole – especially over 7mm (a quarter of an inch) in diameter
* a mole with an uneven or ragged edge
* a mole of varying shades of colour
* a mole with an inflamed or red edge
* a mole that bleeds, oozes or crusts
* a mole that feels different, painful or itches

Don’t use sunbeds

Sunbeds mimic the effect of the sun and give out artificial UVA and UVB radiation. Exposure to artificial UV radiation can also damage your skin. Sunbeds have been linked to an increased risk of skin cancer as well as eye conditions.

An artificial tan from a sunbed doesn’t protect your skin against sunburn on holiday; it’s similar to using a sunscreen with SPF 2 to 3.

There are no regulations relating to the use of sunbeds, but the World Health Organization (WHO) recommends that you shouldn’t use sunbeds if you:

* are under 18
* have sunburn, burn easily or had frequent sunburn as a child
* have a lot of moles
* tend to freckle
* have pre-cancerous or cancerous skin lesions
* are wearing cosmetic products (these may make you more sensitive to UV radiation)
* are taking medication (you should seek medical advice to check whether your medication will make you particularly sensitive to UV radiation)

Winter sun

You can’t feel UV rays. The warmth you feel on your skin is actually caused by the sun’s infrared radiation. So just because you can’t feel the hot rays of the sun, it doesn’t mean you won’t get sunburnt.

The amount of UV radiation is generally lower during the winter but snow reflects most of the sun’s rays, so you can still get sunburnt. If you’re high up in the mountains, there is less atmosphere to block out the UV rays, so make sure you use sunscreen.
Protecting children from the sun

Young skin is sensitive and very easily damaged by the sun. Getting sunburnt as a child is known to increase the risk of developing skin cancer as an adult.

Keep your baby in complete shade. Pop-up shelters are a good way to protect children from the sun on the beach or in the garden. Canopies and parasols for prams and buggies protect children when you’re out and about.

Dress your child in loose-fitting clothes that cover up their arms and legs. A hat with a brim at the front and a cloth flap that covers the neck provides good sun protection. Sunglasses will help to protect your child’s eyes.

Use water-resistant sunscreen with SPF 20 or higher on all exposed areas of your child’s skin and apply generously every couple of hours. If you take your child swimming, re-apply the sunscreen after towel drying.

Fake tans

Fake tanning lotions are a popular alternative to sunbathing and sun beds. The tanning lotion reacts with your skin and produces a brown pigment. Fake tan needs to be re-applied regularly if you want to maintain the tan, because your outer skin cells are shed naturally as your skin grows.

Some fake tanning lotions contain sun protection but the SPF is usually very low, so you should also wear sunscreen with an SPF of 15 or higher when you’re out in the sun.

Although fake tanning lotions aren’t known to be dangerous, they can sometimes trigger an allergic reaction. Always test the lotion on a small area of your skin first to see if you have a reaction.

Sunlight

Sunlight, in the broad sense, is the total frequency spectrum of electromagnetic radiation given off by the Sun. On Earth, sunlight is filtered through the Earth’s atmosphere, and solar radiation is obvious as daylight when the Sun is above the horizon.

When the direct solar radiation is not blocked by clouds, it is experienced as sunshine, a combination of bright light and radiant heat. The World Meteorological Organization uses the term “sunshine duration” to mean the cumulative time during which an area receives direct irradiance from the Sun of at least 120 watts per square meter.

Sunlight may be recorded using a sunshine recorder, pyranometer or pyrheliometer. Sunlight takes about 8.3 minutes to reach the Earth.

Direct sunlight has a luminous efficacy of about 93 lumens per watt of radiant flux, which includes infrared, visible, and ultraviolet light. Bright sunlight provides illuminance of approximately 100,000 lux or lumens per square meter at the Earth’s surface.

Sunlight is a key factor in photosynthesis, a process crucially important for life on Earth.

Life on Earth

The existence of nearly all life on Earth is fueled by light from the sun. Most autotrophs, such as plants, use the energy of sunlight, combined with minerals and air, to produce simple sugars—a process known as photosynthesis. These sugars are then used as building blocks and in other synthetic pathways which allow the organism to grow.

Heterotrophs, such as animals, use light from the sun indirectly by consuming the products of autotrophs, either directly or by consuming other heterotrophs. The sugars and other molecular components produced by the autotrophs are then broken down, releasing stored solar energy, and giving the heterotroph the energy required for survival. This process is known as respiration.

In prehistory, humans began to further extend this process by putting plant and animal materials to other uses. They used animal skins for warmth, for example, or wooden weapons to hunt. These skills allowed humans to harvest more of the sunlight than was possible through glycolysis alone, and human population began to grow.

During the Neolithic Revolution, the domestication of plants and animals further increased human access to solar energy. Fields devoted to crops were enriched by inedible plant matter, providing sugars and nutrients for future harvests. Animals which had previously only provided humans with meat and tools once they were killed were now used for labour throughout their lives, fueled by grasses inedible to humans.

The more recent discoveries of coal, petroleum and natural gas are modern extensions of this trend. These fossil fuels are the remnants of ancient plant and animal matter, formed using energy from sunlight and then trapped within the earth for millions of years. Because the stored energy in these fossil fuels has accumulated over many millions of years, they have allowed modern humans to massively increase the production and consumption of primary energy. As the amount of fossil fuel is large but finite, this cannot continue indefinitely, and various theories exist as to what will follow this stage of human civilization (e.g. alternative fuels, Malthusian catastrophe, new urbanism, peak oil).

Nature’s Healer: The Sun

The sun has always been seen as the source of life and healing. We must not forget the many benefits the sun bestows on us. It is nature’s healer.

Sunlight

Throughout history there has been no better and more common symbol of happiness and well being than the sun. The ancient Egyptians, the Aztecs, Romans and Greeks all worshipped the sun and thought of it as the source of life and health. Regardless of the historical time that comes to mind, you will find people cheered and uplifted by the life-giving rays of the sun.

Whether it was in the form of the god Helios or establishing Sun-day as the first day of the week, the sun always has played an important role in people’s lives.

The great Greek physician Hippocrates wrote extensively about the sun’s healing powers. Herodotus, the father of Heliotherapy, made frequent statements about the healing properties of the sun in his medical practice. In our own time, we see a reflection of these ancient sentiments in songs, poems and movies. And who of us could deny the feeling we have when the sun breaks through the darkened clouds: our mood lifts; our eyes turn upward; our energy and zest for life returns.

Although there have been many serious medical warnings about overexposure to the sun in recent years, we must not neglect the positive role sunlight plays in our mental and physical health. There is good news coming from scientific research telling us why we look and feel better from the sun.

The Blues

Sunlight is an important part of our daily lives. Ever notice how much time is spent at the office worrying about who gets the office with the window. And what about all that energy you feel when spring and summer come around. Everyone seems to be outdoors, planning hikes, barbecues and pool parties. You name it and it’s happening.

Tom Wehr, M.D., a research psychiatrist at the National Institutes of Health, is an expert in mood disorders and feels that our elevation in mood during the spring and summer can be directly linked to the amount of sunlight we are exposed to. “Researchers have found the exposure to natural light increases the production of serotonin, a chemical that stimulates the brain’s pleasure center, thereby perking up your mood while warding off anxiety and depression.”

In contrast, look at what happens to people in the long winter months, especially those living in the Northeast and Northwest. Over 11 million people suffer from what is called Seasonal Affective Disorder or SAD, and another 25 million suffer from a milder form of “winter blues.”

The symptoms of SAD and the “winter blues” can include fatigue, craving carbohydrates, irritability, sleeping more and a change of personality from your summer self to your winter self. It’s not exactly known what causes SAD, but according to health writer Francis FitzGerald, “SAD occurs year after year during a specific season – usually the winter – and vanishes when spring ushers in longer days and more sunshine.”

Medical Researchers think that our depressed moods during the winter may be the result of a chemical imbalance between serotonin and melatonin. With too little sunlight, melatonin makes us drowsy, and disrupts our internal clock.

Our Bodies

Besides just making us feel better and more energetic, exposure to sunlight plays an important role in helping us create vitamin D in our bodies. What makes this so important? Vitamin D has been shown to help prevent and treat serious medical conditions, including: breast cancer, osteoporosis, prostate cancer, psoriasis, acne, etc.

Though many people aren’t aware of it, most of our physiological requirements for vitamin D are provided for by casual exposure to sunlight. It is easy to see how important sunlight is for our physical and mental health.

Breast Cancer

Over 180,000 women will be diagnosed with breast cancer this year. It is a major concern for women of all ages. But there is hope. According to Judy Gaillard and Donald Smith of Sun Wellness magazine, a study by researcher Ester M. John at the Northern California Cancer Center, entitled “Vitamin D and Breast Cancer Risk…” casual exposure to sunlight, along with other factors, can help reduce the risk of breast cancer.

The scientists concluded “high exposure to sunlight was associated with a 25 percent to 65 percent reduction in breast cancer risk among women whose longest residence was in a state of high solar radiation.” A 25 percent reduction in the number of breast cancer cases would mean approximately 44,000 women would not have to suffer the trauma of this disease. Since vitamin D and sunlight exposure are life-style behaviors, this is good news for women wishing to reduce their risk of breast cancer.

Osteoporosis

Sometimes called “the silent disease,” osteoporosis is the loss of bone mass due to the malabsorption of calcium into the bone. Bone fragility results in increased risk of bone fracture in many parts of the body, including the hips, spinal vertebrae, and ribs. According to James F. Balch, M.D., author of Prescription for Nutritional Healing, fully “half of all women between the ages 45 and 75 show signs of osteoporosis.” Although osteoporosis is mostly an issue for post-menopausal women, both sexes and all age groups suffer from this disease.

“If vitamin D is absent, calcium, which is vital for normal bone growth and development, will not be absorbed from the intestinal tract and the bones become deformed,” says Zane Kime, M.D., M.S. in his book Sunlight. One of the best ways to get adequate vitamin D is moderate exposure to the sun. The World Health Organization Task-Force for Osteoporosis recently recommended sunlight as a part of the treatment and management of this disease.

Prostate Cancer

Prostate cancer is the second most common cause of death from cancer in men over age 75. In a recent study by Hanchette and Schwartz of the University of North Carolina and published in the journal Cancer, the researchers a 20 to 40 percent lower incidence of prostate cancer among men in southern climates. Because of findings like this some researcher are suggesting that vitamin D may be an effective preventive agent against prostate cancer. The importance of sunlight cannot be underestimated in maintaining prostate health. If the incidence of prostate cancer is reduced by 20 percent nearly 37,000 men would not suffer the anguish of this disease.

Athletic Achievement

Most of us believe that sunlight gives us extra pep and energy. During the summer months, we tend to sleep less, play more and just have more get up and go. To back up this idea scientifically, Bylle Dopps and Scott Hoover of Sun Wellness magazine looked at research from the Sports Medicine Department of the German National Olympic Team Training Center. The results of their research showed that routine exposure to the sun optimized performance capabilities and reduced the incidence and recovery time of athletes from minor injuries.

If simple sunlight can help world class athletes recover from the stresses of training and competition, it seems reasonable to conclude that we can all benefit from the stress busting affects of sunlight.

Conclusion

Recent scientific studies have demonstrated what humans have suspected all along: natural sunlight promotes feelings of well-being, improves immune function, promotes natural healing and optimizes athletic performance. Don’t neglect these positive benefits of sunlight. Include moderate exposure to the sun in your overall health regimen.