by Ian Wishart
“Paradoxically,” reports Godar’s study, “although outdoor workers get much higher outdoor solar UV doses than indoor workers get, only the indoor workers’ incidence of cutaneous malignant melanoma (CMM) has been increasing at a steady exponential rate.”
“The Godar paper argues that the environment we have created living indoors behind glass since the beginning of the 20th century, which allows exposure to UVA, but not UVB which synthesises vitamin D, is responsible for the epidemic of melanoma,” explains Robert Scragg, a vitamin D expert at New Zealand’s University of Auckland. Office buildings, homes and car windows have been allowing burning UVA radiation through while blocking UVB rays – which actually help generate protective vitamin D3 if they can reach your skin.
The US Food and Drug Administration study found vitamin D3 – created in the skin by suntanning – acts like a timebomb when it is absorbed by melanoma cancer cells.
“Outdoor exposures include UVB (290–320 nm) radiation, so that previtamin D3 and thermal conversion to vitamin D3 can occur in the skin. Vitamin D3 can then be converted to its most hormonally active form, 1a,25-dihydroxvitamin D3 or calcitriol, which kills melanoma cells and SCC (squamous cell carcinoma),” the Godar study reports.
The D3 attaches itself to melanoma cancer cells and explodes them.
“Calcitriol can control or eliminate melanoma cells by binding to the vitamin D3 receptor (VDR) on the nuclear membrane signalling for either growth inhibition or cell death via apoptosis, while it protects normal melanocytes from apoptosis.”
Apoptosis is the way the body normally destroys cancer cells safely, but cancers spread when apoptosis isn’t working properly. Vitamin D3 appears to power-up the body’s natural cancer-destroying mechanisms.
We spend our working lives indoors, and the only times we go out in the sun we slap on a chemical cocktail capable of severely restricting vitamin D production.
Little wonder that an Austrian scientific study in the late nineties found users of sunscreens were a whopping three and a half times more likely to develop melanomas than regular unprotected sunbathers:
“The factor most significantly associated with increased melanoma risk was the use of sunscreens. Subjects who often used sunscreens had an increased odds ratio (OR) of 3.47 (95% confidence interval [CI]1.81-6.64) compared with subjects who never used sunscreens (P = 0.001), after adjustment for sex, age and other significant sunlight-related factors. Skin colour and higher numbers of sunbaths were significant protective factors.”[21]
The Austrian team found that people who sunbathed more than 30 times a year reduced their risk of melanoma by a massive 91%. The only thing that ramped their risk right up again was if they got sunburnt doing it.[22]
A recent Swedish study, based on the knowledge that sunburn can lead to melanoma, examined society’s most vulnerable – our children. Staggeringly, they found children whose parents regularly slopped sunscreen on them were more likely to get sunburnt:
“Sunscreen was an independent risk factor of being sunburnt between 2 and 7 years of age (not or seldom using sun screen was protective)… Swedish children are frequently sunburnt and children living in the south are more sunburnt than those in the north. Sunscreens that were seldom used or not used at all were found to be protective. These results support previous reports that photosensitive skin type is an important risk factor for suffering sunburn as a child and therefore increases the risk of cutaneous malignant melanoma.”[23]
The Monty Python team could not have said it more deftly: “Sunscreens that were…not used at all were found to be protective”.
In other words, parents who encouraged their children to tan naturally and gradually, without sunscreen, turned out to be more responsible than parents who followed official policy advice to slather on the sunscreen.
There are many scientists now daring to suggest that the sunscreen, sunsmart emperor has no clothes.
“Many primary care providers advise patients to use sunscreen as a means to reduce their risk for skin cancer, especially cutaneous malignant melanoma (CMM),” writes Dr Margaret Planta.[24] “Despite the availability and promotion of sunscreen for decades, the incidence of CMM continues to increase in the U.S. at a rate of 3% per year. There currently is little evidence that sunscreens are protective against CMM. A number of studies suggest that the use of sunscreen does not significantly decrease the risk of CMM, and may actually increase the risk of CMM and sunburns.”
Planta warns “providers may need to alter their advice regarding sunscreen use for CMM prevention”.
In 2006, the US Environmental Protection Agency put it on the record with a bald statement of fact, “there is no evidence that sunscreens protect you from malignant melanoma.”[25]
Dr Planta cites more evidence, like the fact that residents of cooler northern US states like Delaware have a higher incidence of melanoma than sunnier southern states like Texas, which again suggests a greater and more regular sun exposure might actually protect against melanoma. Planta, incidentally, still insists sunscreens are necessary, but that the public need to be fully informed of their weaknesses.
“Future studies with humans,” write Burnett & Wang in the conclusion of their own report, “will need to be conducted under real world conditions with modern sunscreens, before we can determine definitively the safety and efficacy of sunscreen.
“However, none of the data published to date conclusively demonstrate adverse effects on the health of humans from the use of sunscreens.”
Dermatologists will frequently tell patients, “by the time you have a tan, the sun has already caused DNA damage inside you”. Statements like this take a significant role in sunsmart messaging. However, whilst true, they are not the whole truth. Getting a tan is the body’s response to UVB radiation – our DNA is actually programmed to repair the “damage” caused by UVB and to manufacture a protective tan as a result. Without the damage, the DNA won’t flip the switch to activate the tan.
Further scientific evidence indicating that dermatologists may not have the full story emerged in a study published February 2012, in the journal Mutation Research.[26] Scientists discovered vitamin D actually prevents DNA from being damaged by free radicals, and maintains genetic integrity. The vitamin also regulates the growth rate of cells and appears to “reduce oxidative damage in humans.”
“Both animal studies and cell culture studies show that vitamin D treatment drastically reduced oxidative stress damage and chromosomal aberrations, and prevented telomere shortening and inhibiting telomerase activity, which also suggested that vitamin D may extend lifespan in humans,” reported journalist David Liu of the findings.[27]
All of these things are what you would expect to find in a complex biological system where life has been reliant on the sun for millions of years. And so far, sun tans are looking a lot more protective against deadly skin cancers than anything humans have devised in the sunsmart arsenal. Maybe the natural response was the best after all.
After all, Cancer Research UK has announced “Over the last 25 years, rates of malignant melanoma in Britain have risen faster than any of the most common cancers.” Melanoma’s drag race up the fatality charts, then, has coincided with a similar mass uptake of sunscreens over the same period.
So what causes melanoma? A cynic at this point might be muttering “sunscreens”, and for all we know that could be true. However, scientists have found some significant risk factors that point to whether you are more likely to develop melanoma.
They include:
Fair skin (29% increase when compared against olive or brown-skinned people)
Very fair skin (183% increase in risk)
Blue/grey eyes (71% increase in risk compared with brown eyes)
Green/hazel eyes (24% increase in risk)
Blonde hair (76% increase in risk compared with black or brown haired people)
Red hair (185% increase in risk)
Able to get moderately tanned (31% increase in risk comp
ared to people who easily tan deeply)
Mild or occasional tans (88% increase in risk)
No suntan at all, or freckled (124% increase in risk)
Additionally, your burn ratio is important. People who go brown without burning had no increase beyond the average risk, but for others:
Mild burning followed by a tan (14% increase in risk)
Painful sunburn followed by peeling (113% increase in risk)
Severe sunburn with blistering (114% increase in risk)
Sunburn before the age of 20 (24% increase in risk compared with people never sunburnt)
Sunburn since 20 (56% increase in risk)
The University of Leeds research unit discovered something else as well:
“We had known for some time that people with many moles are at increased risk of melanoma,” Professor Julia Newton-Bishop explained, but “in this study we found a clear link between some genes on chromosomes 9 and 22 and increased risk of melanoma. These genes were not associated with skin colour.”[28]
It was the first time science had found a genetic link to melanoma that did not involve hair, eye or skin colour. In this case, the genes influenced the number of moles a person has, and hence the number of pre-existing stepping stones that melanoma could spring from. The study determined that at least five genes exist that have an impact on melanoma risk, and most people in the world are carrying at least one of these genes. If you happen to be the lemon in the one-armed-bandit lottery and find you are carrying all five genes, your risk of developing melanoma is 800% higher than a person carrying none.[29]
Here’s something else to think about: if you live in a high UV area like Queensland, sunburn easily or get skin cancer, which has a tiny mortality rate, a new study out of Australia indicates your risk of then developing pancreatic cancer (mortality rate 95% within a year, the remaining 5% soon after) is cut in half.[30] Most people survive breast cancer. The vast majority survive skin cancer. But you don’t walk away from pancreatic cancer.
More people die each year from pancreatic cancer than skin cancer, it is the world’s fourth most deadly cancer measured by number of deaths. Recent high profile victims include Apple co-founder Steve Jobs and actor Patrick Swayze. If it was likely that sunbathing would increase your risk of skin cancer, but reduce your risk of pancreatic cancer by 49%, how would you weigh your relative risk on this?
Tough question, but it’s the kind we need to be asking ourselves because we don’t live in a perfect world, and everything involves a trade-off of some kind.
There’s something else about the pancreatic cancer study that’s confusing researchers: is it vitamin D lowering the risk in this case, or is it sunlight itself? The implications of that are that there may be something protective in the way the human body processes UV radiation that mere vitamin D supplements can’t replicate.
Their logic for saying this is that areas with the highest UV radiation in Australia have the lowest rates of pancreatic cancer, but that some studies have found no impact of vitamin D on this particular cancer.
Then there’s another interesting revelation: sunburn might not be the cause of melanoma, merely an indicator that you are prone to melanoma. It seems like an odd thing to say, but a recent study reported:[31]
“Unfortunately, some aspects of the promotion and analysis of sunscreen use are controversial. Many take the perspective that if sunburns are strongly associated with the development of melanoma, and sunscreens prevent sunburn, then sunscreens will prevent melanoma.
“However…it is likely that sunburn is a clear indicator of the interaction between excessive sun exposure and a susceptible phenotype – that is, severe solar exposure to skin unaccustomed to it – rather than a direct cause of melanoma and basal cell carcinoma.”
In other words, it is not that the sunburn necessarily causes the cancer, it’s just that people most susceptible to skin cancer burn more easily.
What then, can we take away from all this?
That sunscreens are excellent at helping prevent solar aging of the skin, and squamous cell carcinomas.
That there is currently no evidence that sunscreens are of any use at all in the fight against deadly skin cancers like melanoma and basal cell carcinoma.
That there is evidence people who regularly use sunscreen are paradoxically at a much higher risk of developing melanoma.
That if you sunburn easily or fall into a melanoma risk group (fair skin, blue or green eyes etc), it is very important that you do not sunburn.
That sunbathing without sunscreen during summer, but importantly also without burning, confers greater protection against melanoma than using sunscreen, but that this benefit does not exist for high risk individuals, who should use vitamin D supplements rather than sunlight.
That, used correctly, sunscreens make it impossible for your body to absorb healthy amounts of vitamin D.
That, seeing as most people don’t use sunscreens correctly, those users are still getting some, if not the optimum amount, of vitamin D in summer.[32]
The inconvenient truth about sunscreens, melanoma and cancer generally appears to be this: there is no easy solution. If you want youthful radiant skin, the price of beauty appears to be a much higher risk of breast, colon or other cancers of the internal organs, heart disease, Alzheimer’s, multiple sclerosis, mental illness or a range of other nasties we’ve covered off in this book.
In short, it’s a trade-off. The less sunlight you get, the happier your dermatologist will be, but the wealthier your oncologist, cardiologist and psychotherapist might become.
So what if you are one of those people who burns easily or who – despite what you’ve read here about the natural benefits of UV – doesn’t want to spend time in the sun – how do you get sufficient vitamin D? As we’re about to see, there are some alternative options.
[1] “UV protection and sunscreens: What to tell patients”, Jou et al, Cleveland Clinic Journal of Medicine, Vol 79, number 6, June 2012, pp427-436
[2] “Sunscreen use and malignant melanoma”, Westerdahl et al, International Journal of Cancer, 1 July 2000, Vol 87, issue 1, pp145-150
[3] “Ultraviolet radiation reports shine light on how pediatricians can help patients avoid skin cancer”, Sophie J. Balk, M.D., FAAP, http://aapnews.aappublications.org/content/32/3/32.short
[4] “Where the Rubba Meets The Road”, Wishart & Morrow, Investigate magazine, July 2005, http://issuu.com/iwishart/docs/investigate_july05/39
[5] “Serum 25-Hydroxyvitamin D3 Levels are Associated With Breslow Thickness At Presentation and Survival From Melanoma”, Newton-Bishop et al, Journal of Clinical Oncology, 21 September 2009, DOI:10.1200/JCO.2009.22.1135
[6] Peak UV levels in New Zealand and Australia are 40% higher than peak levels in the UK or North America, according to the official position statement on UV and cancer published by the New Zealand Government’s Ministry of Health
[7] A cautionary note. The protective effect of sunbathing did not extend to people with freckles, or photo sensitive skin. A common sense approach suggests vitamin D supplements are a better bet for those individuals.
[8] In the interests of balance, it is worth pointing out that our sun has been more active over the past century than in the previous one thousand years. That was announced by the Max Planck Institute for Solar System Research in Germany in 2004 and reported in The Telegraph, 19 July 2004.
[9] “UV Protection and Sunscreens”, Jou et al, Cleveland Clinic Journal of Medicine, Vol. 79, No. 6, June 2012
[10] Ibid, sub-referencing “Sunscreen abuse for intentional sun exposure” by Autier, P. Br Journal of Dermatology 2009; 161(suppl 3):40-45
[11] “Prolonged prevention of squamous cell carcinoma of the skin by regular sunscreen use”, Van der Pols et al, Cancer Epidemiol Biomarkers Prev 2006;15:2546-2548
[12] “The Good, the Bad, and the Ugly of Sunscreens,” M Berwick, Clinical Pharmacology & Therapeutics, Jan 2011, doi:10.1038/clpt.2010.227
[13] “Su
nscreen plain English Questions and Answers, 14 February 2012” NZ Cancer Society pamphlet, http://www.cancernz.org.nz/assets/files/info/SunSmart/Sunscreen%20QA%27s_14Feb2012%283%29.pdf
[14] “Dark Side of Tanning Campaign conveys deadly message to young Victorians this summer”, Sunsmart Australia news release, 2 December 2010
[15] “Reduced Melanoma after Sunscreen Use”, Green et al, Journal of Clinical Oncology, 2011; 29:257-263
[16] “UV Protection and Sunscreens etc”, Jou et al, citing a follow up response, “Increased Melanoma After Regular Sunscreen Use?”, Goldenhersh & Koslowsky, Journal of Clinical Oncology, 2011, 29:e557-e558
[17] “In vitro UV-A protection factor (PF-UVA) of organic and inorganic sunscreens”, Couteau et al, Pharmaceutical Development and Technology, 2009;14(4):369-72, http://www.ncbi.nlm.nih.gov/pubmed/19630696?dopt=Abstract
[18]http://www.pgbeautyscience.com/assets/files/research_updates/UV%20Toolkit%20063005.pdf
[19] “The Truth About Sunscreen and Effective Patient Education”, Lawrence Samuels MD, Practical Dermatology, March 2011:27-32, http://www.bmctoday.net/practicaldermatology/pdfs/0311%20sunscreen%20feature.pdf
[20] “Increased UVA exposures and decreased cutaneous Vitamin D(3) levels may be responsible for the increasing incidence of melanoma”, Godar et al, Medical Hypotheses. 2009 Apr;72(4):434-43
[21] “Phenotypic markers, sunlight-related factors and sunscreen use in patients with cutaneous melanoma: an Austrian case-control study”, Wolf et al, Journal of Melanoma Research, 1998 Aug;8(4):370-8, http://www.ncbi.nlm.nih.gov/pubmed/9764814?dopt=Abstract
[22] In contrast to the impact of sunbathing on reducing melanoma risk, the current ‘darling’ of dermatology is aspirin, with a number of reports suggesting low-dose aspirin daily can cut your risk of melanoma. If you read the following study, you’ll see the risk reduction is 13% over a seven year period. Not quite a 91% risk reduction! See “Nonsteroidal anti-inflammatory drugs and the risk of skin cancer: A population-based case-control study,” Johannesdottir et al, Cancer, online 29 May 2012, doi: 10.1002/cncr.27406