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What Every Runner Needs to Know About Sun Safety – Part 2:
Want a Sexy Tan (I Mean, Skin Cancer)?
August 22, 2016 Lindsey N. Dyn
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Disclaimer: I am not a doctor of any kind. I never attended medical school. The information in this article was derived from a variety of resources which can be found in the References at the end of this posting. This article is meant as a vehicle for awareness and is not meant to be interpreted as medical advice.
Do you find wrinkles sexy? Do excessive sunspots really get you going? No? Then why do you still insist on getting a dark, summer tan?
In Part 1 last week we skimmed the surface and provided some of the basics on what UV radiation is and some of the factors that can affect the levels of UV radiation you receive. Today’s article is where you really need to start paying attention. The dangers of UV radiation extend far past painful and unsightly sunburns. We’ll jump in to the long-term effects UV radiation can produce and biggest secret the tanning industry doesn’t want you to know.
Dangers of UV Radiation
Is there really a need to be concerned about UV radiation? Yes! UV radiation has cumulative damaging effects. We need to be concerned about both types of UV radiation, as each type has the potential to affect the skin and our health in different ways. The cosmetic effects of UVA exposure include decrease in the skin’s elasticity, and thus increases in the prevalence of wrinkling. Of more serious concern is UVA’s negative influence on the immune system, which can contribute to skin cancer.(1) UVB radiation, often associated with causing those painful sunburns, also expresses the ability to suppress the immune system, (1) and can cause skin cancer as well (2).
It’s not just the occasional sunburn you get on vacation that impacts your health, but your overall lifetime UV profile. The effects of “UVA manifest usually after a long duration of exposure, even if doses are low” (1). What first surprised me was the finding that a “majority of a person’s lifetime exposure occurs before age 18” (3). We can’t turn back time, but we can aim to improve upon our current sun safety habits. Recognizing the need to create some form of easy awareness for citizens, the World Health Organization, World Meteorological Organization, United Nations Environment Programme, and International Commission on Non-Ionizing Radiation Protection came together to develop the Global Solar UV Index (UVI). The UVI is a means of measuring the intensity of UV radiation on the Earth’s surface with regard to the effects on the skin and communicating the potential dangers to the public. The scale ranges from 1 to 11+, with protection needed as early as level 3. (3)
Source/References = 3, 4
Going through the math calculations in Part 1, we’ve covered why UV radiation can be harmful – the theoretical basis. (If you skipped that portion, no problem – you can take my word or the say-so of thousands of much smarter scientists.) But where’s the support for the various alphabet soup governmental and international agencies (FDA, CDC, WHO) putting out warnings or statements as to the detrimental effect of improper UV exposure? You don’t have to just take their word for it – here’s a brief look into just some of the research to back it up.
Based on hundreds of studies (in mice) an indisputable link has been established between UV radiation and skin cancer (5). In 2009, The International Agency for Research on Cancer (IARC) convened to disseminate a comprehensive review of existing research on UV exposure and skin cancer. It concluded, and later published in 2012, that an overwhelming number of studies showed a positive link between basal cell carcinoma and incidence of sunburn (5). Using data to determine the relationships between UVA and UVB exposure and the incidence rates of various types of skin cancer, at least one study found support for the claim that melanoma may be induced by UVA exposure (5). While that study investigated UVA’s role in inducing melanoma, it is a fact that “the primary cause of melanoma is known: DNA damage resulting from exposure to ultraviolet light” (6). Data from the Surveillance, Epidemiology, and End Results Program by the National Cancer Institute revealed a steady increase in the number of newly diagnosed melanoma cases since the early 1990’s (6). Melanoma is becoming “a significant public health problem. Each year, 75,000 people in the United States are diagnosed with and 10,000 die from the disease” (6).
It’s not just your skin you need to be concerned about, however. Exposure to UV radiation has also been linked to causing ocular melanoma and cataracts. (7) UVB radiation has been singled out as a major culprit, with exposure to this radiation type serving as a major risk factor in developing cataracts (3). Cataracts isn’t a condition to take lightly, as it is “the leading cause of blindness in the world” (3). While people with darker complexions have more melanin (which provides more UV protection), the “risk of UV radiation-related health effects on the eye and immune system is independent of skin type” (3).
Naturally occurring sunlight isn’t the only type of UV radiation to be concerned about, however. Since the 90’s, I can recall seeing various tanning salons popping up throughout my hometown. Should we really be all that concerned with tanning beds? I’ve regularly heard the excuse that people tan to get a base layer of protection so they don’t get burned later on their vacation. Tans do NOT serve as adequate sun protection. Dark tans on folks with naturally pale complexions only provide the equivalent of an SPF of approximately 4. (3) Perhaps you’re thinking, ‘I usually only tan for a few minutes. It can’t really be that bad, right?’
#Truth in Tanning – What the tanning industry doesn’t want you to know
YES, it IS that bad! “Indoor tanning is designed to give you high levels of UV radiation in a short time.” (7) (emphasis added by this author). How high? “UV emission of a modern tanning appliance corresponds to an UV index of 12, i.e. equivalent to midday tropical sun” (5). Perhaps even more alarming, according to the IARC publication, the tanning beds in use primarily emit UVA radiation (5). A number of studies have sought to investigate the influence of tanning beds on cancer risk. Of the studies involving artificial UV radiation reviewed by the IARC, all of them demonstrated “an increased risk for melanoma when exposure started before approximately 30 years of age” (5).
But, perhaps our perception of the tanning industry is overblown (note sarcasm). Exactly how big of a problem is indoor tanning? To assess the prevalence of the indoor tanning phenomenon, researchers conducted a meta-analysis of 88 studies published between 1992 and 2013. Published in The Journal of the American Medical Association Dermatology in 2014, results from more than 490,000 participants revealed the following:
When surveyed whether participants had ever used indoor tanning,
35.7% of adults,
55.0% of university students, and
19.3% of adolescents responded yes.
When surveyed whether participants had used indoor tanning in the past year,
14.0% of adults,
43.1% of university students, and
18.3% of adolescents responded yes.
When the authors applied the data to determine attributable risks for the various types of skin cancer, they estimated almost 420,000 cases of skin cancer could be attributed to indoor tanning use each year, in the United States alone. As a comparison, the authors also quoted recent estimates of lung cancer cases in the U.S. These paled in comparison, with only 226,160 cases cited. (8)
The greater scientific and health-related minds of the world are not blind to the research and statistics. The World Health Organization (WHO) has classified indoor tanning as a group 1 carcinogen (8). That means it causes cancer! Why would you pay to voluntarily bake in an appliance that has been shown to cause cancer?! Other countries have wised up; Brazil and Australia have completely banned indoor tanning, and at least 11 European countries have banned indoor tanning for people under the age of 18. (7) Slowly the United States is realizing the dangers of indoor tanning and enacting restrictions. However, we have a long way to go. Currently the regulations vary on a state-by-state basis, and are restricted primarily to minors under the age of 18.(7) For a look at restrictions of indoor tanning by state, check out the National Conference of State Legislatures’ Indoor Tanning Restrictions for Minors: A State-by-State Comparison (9). Also an encouraging step in the right direction, the FDA has proposed a rule that would restrict minors under the age of 18 from using indoor tanning, effective at the federal level. Beefed up warnings for adults would also be included if the rule passes. To find out more about the FDA’s proposed indoor tanning safety measures, check out “FDA Proposes New Safety Measures for Indoor Tanning Devices: The Facts” (10).
These facts and statistics aren’t meant to scare you into living your entire life indoors, but rather are a cautionary tale as to the importance of proper sun safety. That was a lot of information to digest so we’re going to let it sink in. Stay tuned for the next sun safety article featuring tips on selecting a proper sunscreen and other useful sun safety tips. Until next time, happy running!
1.) Latha, M.S., Martis J., Shobha, V., Shinde R.S., Bangera, S., Krishnankutty, B., Bellary, S., Varughese, S., Rao, P., Kumar, B.R.N. Sunscreening Agents: A Review, The Journal of Clinical and Aesthetic Dermatology, Jan 2013; 6(1): 16-26.
2.) American Academy of Dermatology. Sunscreen FAQs, https://www.aad.org/media/stats/prevention-and-care/sunscreen-faqs accessed 7/19/2016.
3.) World Health Organization. Global Solar UV Index: A Practical Guide. 2002.
4.) World Health Organization. Global UV Project Intersun. http://www.who.int/uv/intersunprogramme/activities/uv_index/en/index1.html accessed 8/8/2016.
5.) International Agency for Research on Cancer. Solar and Ultraviolet Radiation. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, 100D 2012: 35-101.
6.) Sharfstein, J.M., A Spotlight on Sunscreen Regulation, N Engl J Med 2015; 373: 101-109 DOI: 10.1056/NEJMp1504912.
7.) Centers for Disease Control and Prevention. Indoor Tanning is Not Safe, http://www.cdc.gov/cancer/skin/basic_info/indoor_tanning.htm accessed 7/19/2016.
8.) Wehner, M.R., Chren, M.M., Nameth, D., Choudhry, A., Gaskins, M., Nead, K.T., Boscardin, W.J., Linos, E. International Prevalence of Indoor Tanning: A Systematic Review and Meta-analysis. JAMA Dermatol. 2014 April; 150(4): 390-400.
9.) National Conference of State Legislatures. Indoor Tanning Restrictions for Minors: A State-by-State Comparison, http://www.ncsl.org/research/health/indoor-tanning-restrictions.aspx accessed 8/1/2016.
10.) U.S. Food and Drug Administration. FDA Proposes New Safety Measures for Indoor Tanning Devices: The Facts, http://www.fda.gov/ForConsumers/ConsumerUpdates/ucm350790.htm accessed 8/1/2016.