Do Aussies need more time in the sun?

GOLD COAST, Australia — In a strange twist, the sun-soaked citizens of Down Under are becoming vitamin D deficient, making them vulnerable to a multitude of cancers.

Could it be a case of public health campaigns — accelerated in the 1980s, after scientists discovered a hole in the ozone layer that would let unfiltered UV rays through to the earth with dangerous consequences — working a little too well on those living in the “skin-cancer capital of the world?”

In western Australia and the northeastern state of Queensland, vitamin D deficiency has rarely been cause for concern among young people, who pride themselves on an outdoor lifestyle that takes full advantage of the country's vast coastline.

However, studies have found young adults to be either deficient or largely insufficient in the important vitamin, which is now strongly linked with colon, prostate and breast cancers, along with the skin cancer, melanoma. In Queensland, also known as the Sunshine State, studies have shown vitamin D deficiencies in up to 40 percent of people tested.

Figures point to lifestyle choices as a probable cause.

Despite their adoration for the beach and the huge population migration toward coastal living, Australians also work some of the longest hours in the Western world. Like Americans and Europeans, they spend much of their day commuting in trains, buses and cars, and often spend lunch breaks sitting at their desks. The elderly also tend to spend more time indoors: the average age of an Australian melanoma patient is 80, indicating that their disease is the result of a long life of exposure to the sun.

So, are Australian's fears of developing skin cancer — stoked by two decades of public awareness campaigns that range from the catchy to the downright scary — unfounded?

Rebecca Mason, professor of physiology at the Bosch Institute, University of Sydney, points to research from Omaha, in the United States, and studies from the United Kingdom and Germany that suggest a complicated relationship between sunlight and melanoma. The studies from Europe conclusively found that a small amount of sun exposure on the hands, face and neck on a regular basis may in fact protect against the skin cancer melanoma, even after diagnosis and the initial removal of cancerous tissue.

Evidence also showed that if a patient had a melanoma removed in the summer months when their vitamin D levels were higher, their chances for survival were vastly improved.

Contrast this with the message broadcast by government-sponsored groups such as the Cancer Council Australia:

  • Skin cancers account for 80 percent of all newly diagnosed cancers in Australia each year;
  • Two in three Australians will be diagnosed with skin cancer by the time they are 70;
  • More than 10,000 Australians are treated for melanoma each year, of which around 1,250 die;
  • Melanoma is the most common cancer in Australian aged 15-44 years;
  • Australia has one of the highest incidences of skin cancer in the world, at nearly four times the rates in Canada, the U.S. and the U.K. 

Regardless, the issue of a vitamin D deficiency is occupying a new generation of researchers.

Why the concern?

Research suggests that the vitamin may slow the growth of cancer cells, especially after an initial melanoma is removed, and that it may strengthen the immune system’s response to some cancers. There is an especially strong link with colon cancer, but vitamin D deficiency has also been linked with susceptibility to multiple sclerosis, Type 1 diabetes, high blood pressure and rheumatoid arthritis.

In a proposed new study, a team from the University of Sydney will be working with the Australia and New Zealand Melanoma Trials Group with the aim of giving high-risk skin cancer patients large oral doses of vitamin D as part of their treatments. Much evidence already points to benefits for skin cancer patients taking this approach.

According to the American Medical Association:

  • Each year, over 1 million cases of skin cancer are diagnosed in the United States;
  • Squamous cell carcinoma has a 95 percent cure rate if detected early, but in 1998 about 1,200 died from this type of skin cancer;
  • One in 79 Americans has a lifetime risk of developing melanoma;
  • One person dies every hour from melanoma.

In the meantime, debate continues about just what is the ideal amount of exposure to the intense Aussie sun.

Mason suggests a “little and often” approach to sun exposure, or the safer choice of a vitamin D supplement, combined with calcium and exercise. However, she stresses the standard advice to stay out of the sun at what she calls the “witching hours” — the hottest times of the day, between 11 a.m. and 3 p.m.

Rodney Hannaford, the medical director of the Skin Cancer Foundation of Australia, says protecting oneself against skin cancer is about taking the view of a “lifetime program” of sensible sun exposure.

“We deal with people on an individual basis and each patient is assessed on their merits. An elderly person who spends a lot of time indoors might be encouraged to go out in the sun a bit more to boost their vitamin D levels," he says. “It’s about doing what’s sensible for you. You do get the odd person who just locks themselves away and completely stays out of the sun. That might be taking things too far. There is no evidence to support that working."

“The most horrifying thing is when people come in with a tan and say that they’ve been on holiday and they got sunburned and would like a check-up. At that point we say to them, well, you’re going to need check ups for the next 60 years now,” Hannaford says.