Exposure to ultraviolet (UV) radiation - from the sun, tanning beds, lamps or booths - is the main cause of skin cancer, accounting for around 86% of non-melanoma and 90% of melanoma skin cancers. In addition, excessive UV exposure can increase the risk of eye diseases, such as cataract and eye cancers.
The health risks associated with exposure to UV radiation have certainly been well documented, so much so that the World Health Organization (WHO) have now officially classed UV radiation as a human carcinogen.
This year alone, Medical News Today reported on an array of studies warning of UV exposure risks. One study, published in the journal Pediatrics, revealed that tanning bed use among youths can increase the risk of early skin cancer, while other research found that multiple sunburns as an adolescent can increase melanoma risk by 80%.
Furthermore, in response to reported health risks, the Food and Drug Administration (FDA) recently changed their regulation of tanning beds, lamps and booths. Such products must now carry a visible, black-box warning stating that they should not be used by anyone under the age of 18.
How does UV radiation cause damage?
UV radiation consists of three different wavebands: UVA, UVB and UVC. The UVC waveband is the highest-energy UV but has the shortest wavelength, meaning it does not reach the earth's surface and does not cause skin damage to humans.
Tanning beds and tanning lamps primarily emit UVA radiation, sometimes at doses up to 12 times higher than that of the sun.
However, UVA has a long wavelength and accounts for 95% of solar UV radiation that reaches the earth's surface, while UVB - with a middle-range wavelength - accounts for the remainder. Tanning beds and tanning lamps primarily emit UVA radiation, sometimes at doses up to 12 times higher than that of the sun.
Both UVA and UVB radiation can damage the skin by penetrating its layers and destroying cellular DNA. UVA radiation tends to penetrate deeper layers of skin, known as the dermis, aging the skin cells and causing wrinkles. UVB radiation is the main cause of skin reddening or sunburn, as it damages the outer layers of the skin, known as the epidermis.
Excessive UV exposure can cause genetic mutations that can lead to the development of skin cancer. The browning of the skin, or a tan, is the skin's way of trying to stop further DNA damage from occurring.
Of course, it is not only the skin that can be subject to damage from UV radiation. Bright sunlight can penetrate the eye's surfaces tissues, as well as the cornea and the lens.
Ignoring the risks of UV exposure
But regardless of the numerous studies and health warnings associated with UV exposure, it seems many of us refuse to take note.
A 2012 survey from the Centers for Disease Control and Prevention (CDC) found that 50.1% of all adults and 65.6% of white adults ages 18-29 reported suffering sunburn in the past 12 months, indicating that sun protection measures are not followed correctly, if at all.
A more recent study from the University of California-San Francisco stated that the popularity of indoor tanning is "alarming" - particularly among young people.
The study revealed that 35% of adults had been exposed to indoor tanning, with 14% reporting tanning bed use in the past year. Even more of a concern was that 43% of university students and 18% of adolescents reported using tanning beds in the past year.
Overall rates of tanning bed use, the researchers estimate, may lead to an additional 450,000 non-melanoma and 10,000 melanoma skin cancer cases every year.
It seems unbelievable that so many of us are willing to put our health at risk to soak up some sunshine. So why do we do it?
The desire for a 'healthy tan'
A recent study published in the journal Cell suggested that UV radiation causes the body to release endorphins - "feel-good" hormones - which makes sun exposure addictive.
But Tim Turnham, executive director of the Melanoma Research Foundation, told Medical News Today that many people simply favor a tanned body over health:
"Despite elevated awareness of the dangers of UV radiation, people still choose to ignore the dangers in the pursuit of what they consider to be a 'healthy tan.' This is particularly an issue among young people who tend to ignore health risks in favor of enhancing their social status and popularity. We know that tanning appeals to people who are interested in being included, and this is a primary driver for teens - being part of the 'in' crowd."
Anita Blankenship, health communication specialist at the CDC, told us that the desire for a tan is particularly common among young women.
"In the US, nearly 1 in 3 young white women ages 16-25 years engages in indoor tanning each year," she said. "These young women may experience pressure to conform to beauty standards, and young people may not be as concerned about health risks."
Turnham agreed, telling us that the indoor tanning industry specifically targets this population. "Aggressive marketing, deep discount and package deals are used routinely by tanning salons, who market their services preferentially to young women," he said.
Blankenship added that the public are also presented with "conflicting messages" when it comes to the safety of excess UV exposure. She pointed out that a recent US report found that only 7% of tanning salons reported any harmful effects from tanning beds, booths or lamps, while 78% reported health benefits.
"It is important to monitor deceptive health and safety claims about UV exposure, as they may make it difficult for consumers to adequately assess risk," she told us.
"It is important for people to understand that tanned skin is damaged skin, and that damage can lead to wrinkles and early aging of the skin, as well as skin cancer including melanoma - the kind of skin cancer that leads to the most deaths."
Progress has been made, but more needs to be done
This month is UV Safety Month - an annual campaign that aims to increase public awareness of the health implications caused by UV exposure.
With the help of such campaigns and an increase in studies detailing UV risks, many health care professionals believe there has been a change for the better in attitudes toward UV exposure.
Many health care professionals believe much progress has been made in increasing awareness of UV exposure risks in recent years, but more needs to be done.
"Certainly the scientific community, a number of federal agencies, and possibly the general public are more aware of the risk of UV exposure," a spokesperson from the National Cancer Institute (NCI) told Medical News Today.
"Action and more coordinated efforts increased markedly about 4 years ago, when a number of epidemiological studies documented the harms of indoor tanning, the FDA held their scientific advisory committee meeting to discuss need for changing indoor tanning device regulations, and they also acted on their previous proposals to change sunscreen regulations."
The spokesperson continued:
"We think these summaries acted as a catalyst for efforts to make the public and policy makers aware of the risks of indoor tanning, and also they gave a boost to efforts to increase awareness of outdoor sun exposure risks and encourage sun safe protective behaviors."
In addition, some studies have indicated that many youngsters may even be moving away from the use of tanning beds. A recent Youth Risk Behavior Survey found that among high school students, indoor tanning activity decreased from 15.6% in 2009 to 12.8% in 2013.
Turnham told us that since sunless tanning - such as the use of spray tans - is on the increase, it may be that youngsters are using this as an alternative to tanning salons. But the NCI spokesperson said such an association needs to be investigated before any conclusions can be reached:
"We do not know if changes in indoor tanning are related to increases in use of spray-on and sunless tanning products and services," they told us. "Some studies indicate that sunless products and services are used by people who continue to engage in indoor tanning, but it is an area we continue to research. We are hopeful that we will be able to measure this in an upcoming national survey supplement that is being developed by NCI and CDC."
But despite widespread efforts to increase UV safety awareness, Turnham believes there is still a lot more that can be done to protect public health:
"Regulators could and should do much more to fight the ravages of UV exposure. We need federal legislation banning the use of tanning beds by minors. We need more funding for awareness and prevention efforts."
He added that doctors can also play a role in increasing UV exposure awareness by warning patients of associated risks - something the US Preventive Services Task Force (USPSTF) recommend. They state that health care providers should counsel fair-skinned youths between the ages of 10 and 24 about the risks of indoor tanning and how to protect themselves against UV radiation from the sun.
However, Turnham noted that doctors do not have much time with each patient and proposes that signage in waiting areas warning of the risks of UV exposure may also be effective.
Protecting against UV radiation
Whether there will be further regulation for indoor tanning or an increase in awareness efforts is unclear. But one thing is certain: we can help ourselves to avoid the negative health implications associated with UV exposure.
The American Cancer Society note that young children need extra protection from the sun, as they spend more time outside and can burn easily.
The CDC recommend the following for protecting against UV radiation:
- Stay in the shade if possible, particularly when the sun is at its strongest - usually around midday
- Wear clothing that covers your arms and legs
- Wear a wide-brimmed hat that provides shade for your head, face, ears and neck
- Wear wrap-around sunglasses that protect against both UVA and UVB radiation
- Use sunscreen with a minimum sun protection factor (SPF) of 15 that protects against UVA and UVB radiation, and reapply every 2 hours
- Avoid indoor tanning.
In addition, the American Cancer Society note that young children need extra protection from the sun as they spend more time outside and can burn easily. They add that babies younger than 6 months should be kept out of direct sunlight and be covered with protective clothing. Sunscreen should be used on any exposed areas of skin.