The Sunlight Paradox: How Public Health Campaigns against Sun Exposure May Worsen Health in the British Isles

SAHAR ASHRAFZADEH

Vitamin D
Photo by Colin Dunn, “Vitamin Packaging” via Flickr. Creative Commons Attribution.

We’ve all heard the warnings: exposure to the sun’s UV rays increases one’s risk of skin cancer. It is estimated that over 60% of melanomas and 90% of non-melanoma skin cancers are the result of excess sun exposure.1 As the ability to prevent skin cancer became better known in the 1980s, health officials in Australia introduced programs that advised individuals to avoid midday sunrays and cover up with clothing and sunscreen. The World Health Organization soon endorsed these recommendations, broadening anti-UV campaigns to a global scale. Following suit, the United Kingdom and Ireland enacted programs that encouraged their populations to avoid spending time in the sun and to use sun protectant when outdoors.2

But skin cancer prevention campaigns shouldn’t discredit sunlight’s positive effects, particularly in areas that already receive low amounts of sunshine. Sunlight contains ultraviolet B (UVB), which enables synthesis of vitamin D in the skin.3 Vitamin D is necessary for bone health, and as recent research suggests, prevention of cancer, diabetes, heart disease, and multiple sclerosis.2 The US Institute of Medicine asserts that serum 25-hydroxyvitamin D [25(OH)D] (a precursor of active vitamin D) concentrations in blood should be greater than 50 nmol/L to maintain bone health.4,5 However, most of the population in the British Isles has serum levels well below this minimum.5 A study found that over 45% of British adults have blood serum levels under 40 nmol/L during the winter and spring, when the sunshine is most absent.6 In Scotland, the average 25(OH)D concentration is only 37.5 nmol/L, and almost half of those residing in the least sunlit areas of the country have serum concentrations under 25 nmol/L.4

Numerous factors contribute to the alarming prevalence of vitamin D deficiency in the British Isles. The UK and Ireland have cloudy skies with only a few months of direct sunshine, which itself is often low in strength.2 By contrast, Australia’s climate allows for abundant and intense sunrays with a high UV index year-round.3 Due to these regions’ distinct climates, it is unwise for policies on sun exposure in the British Isles to be based on those of Australia. Individuals residing in the British Isles are already receiving limited sunlight; public health campaigns that advocate for sun avoidance only exacerbate the issue.2 Despite widespread vitamin D deficiency among adults, public health departments in the UK and Ireland recommend neither dietary supplements nor vitamin D fortification of foods, as is common practice in many countries including the United States and Canada.5 As Oliver Gillie writes in his paper titled “Sunlight robbery: A critique of public health policy on vitamin D in the UK,” “We are victims not only of our challenging climate but also of public health policies that maintain low levels of sun exposure as well as a low intake of dietary and supplementary vitamin D.” Together, these factors have caused a vitamin D deficiency pandemic across the British Isles, which may contribute to the increased incidence of cancer, heart disease, diabetes, and multiple sclerosis in the UK compared to other European nations.2

Together, these factors have caused a vitamin D deficiency pandemic across the British Isles, which may contribute to the increased incidence of cancer, heart disease, diabetes, and multiple sclerosis in the UK compared to other European nations.”

Recently, the UK and Ireland have recognized that previous warnings against sun exposure were mistaken; new policies involve emphasis of sunburn avoidance rather than evading sunshine altogether.2 Still, the misguided years demonstrate the paradoxical nature of public health efforts: policies that are beneficial to one population can be potentially harmful to another. Before adopting public health programs from other nations, it is crucial to consider the context in which the programs were created in order to determine whether it is appropriate for a specific population. In the case of sunshine, sometimes the benefits outweigh the risks.

Works Cited:

  1. Fry, Alison, and Julia Verne. “Preventing skin cancer.” BMJ 326.7381 (2003): 114-115.
  2. Gillie, Oliver. “Sunlight robbery: A critique of public health policy on vitamin D in the UK.” Molecular nutrition & food research 54.8 (2010): 1148-1163.
  3. “Risks and Benefits of Sun Exposure Position Statement.” Cancer Council Australia. ATLAS, 3 May 2007. Web. 26 Dec. 2014. <http://www.cancer.org.au/content/pdf/CancerControlPolicy/PositionStatements/PSRisksBenefitsSunExposure03May07.pdf>.
  4. Rhein, Helga M. “Vitamin D deficiency in Scotland.” BMJ: British Medical Journal 348 (2014).
  5. Holick, Michael F. “The vitamin D deficiency pandemic: A forgotten hormone important for health.” Public Health Rev 32.1 (2010): 267-83.
  6. Hyppönen, Elina, and Chris Power. “Hypovitaminosis D in British adults at age 45 y: nationwide cohort study of dietary and lifestyle predictors.” The American journal of clinical nutrition 85.3 (2007): 860-868.

 Sahar Ashrafzadeh is a Brevia contributing writer. She can be reached at sashrafzadeh@college.harvard.edu.