An earlier article by The Master (sorry, I don’t have the link) mentions that human skin colors darken the closer a population is to the equator.
What happened in the case of (Northern) Australia, where a significant fraction of the population migrated from northern/European climates? In a bit over 200 years they haven’t had much opportunity to evolve a darker skin color.
So, are they more susceptile to to skin cancer or other such problems? (I’m assuming, perhaps wrongly, that lighter-skin+more-sun=higher-risk-of-skin-cancer - correct me if wrong.)
For starters
[ul]
[li]Australia has the highest skin cancer incidence rate in the world1.[/li][li]Australians are four times more likely to develop a skin cancer than any other form of cancer2.[/li][li]Approximately two in three Australians will be diagnosed with skin cancer before the age of 703.[/li][/ul]
Source: http://www.health.gov.au/internet/skincancer/publishing.nsf/Content/fact-2
Even Aborigines can get skin cancer.
It’s really only over the last 30 years or so that the general community has started to take the problem of skin cancer/s seriously. Once upon a time it was considered absolutely normal to get sunburnt a few times a year, and any kid who didn’t have a bright red and peeling nose/shoulders by the time school went back in early Feb was regarded as a bit weird.
Nowadays, no child can go outside for school breaks unless they have a wide-brimmed hat on. Applications of SP30 sunscreen and/or wearing of long-sleeved shirts and pants are necessary for anything longer than a brief sojourn out in the sun. SLIP SLOP SLAP, a publicity campaign by the Cancer Council of Australia really brought home the necessity for protection from our harsh sun, especially for people of Anglo-Saxon origins.
kam…who has scars all over from skin-cancer removals thanks to being as white as a lily and growing up at the seaside.
Yes but my Australian friends tell me now, that as a direct result of the “slip/slop/slap” campaign, there is an epidemic of rickets amongst Australian kids.
Plus those kids that do, on occasion, get to go outside suffer from even worse sunburn than they would have had if they had periodic exposure to direct sunshine. By this means they increase their susceptibility to skin cancer.
However, I am led to understand that the question of sun exposure being the cause of skin cancer is controversial and unproven.
My Australian friends have pointed out that the Cancer Council cannot explain the fact that dark skinned people in the tropics get skin cancer on the soles of their feet. How does that happen?
I am told that the actual incidence of skin cancer is very low, and statistically very low on the causes of death amongst the Australian population. The total number is growing only because the total population of Australia is growing.
So the cost of preventing a few cases of skin cancer fifty years from now, is being paid for by a lot of kids today; assuming there is a cause and effect relationship.
Sounds like another manufactured crisis aimed at providing employment for the promoters of yet another dubious cause.
A long time ago I saw a photo in National Geographic of an Australian backcountry guide who had spent a lot of time in boats on rivers. It was a profile and he was holding his artificial nose out a few inches from his face. He had had melanoma in his nostrils, presumably from all the sunlight reflecting off of the water.
Unless you have another cite Grateful-Undead it appears that you may have been slightly misinformed.
Although this relates only to the decade between 1993 and 2003, the article states that although this is the largest case of vitamin D deficiency causing rickets in a developed country, the cases presented are “…almost exclusively recent immigrants or first generation off-spring of an immigrant parent with maternal vitamin D deficiency and exclusive or prolonged breast feeding.”
Of the 126 cases reported, 37% of these children were from the Indian subcontinent, 33% from Africa, 11% from the Middle East, and 4% Australian white children.
I’m not disputing your point of the re-emergence of rickets, I’m just putting some perspective on that.
The increase in rickets in Australia is real but is not primarily attributable to the sun protection program. It is mainly a disease of immigrants to Australia and their first generation children, mainly from Africa, the MidEast and the Indian subcontinent, and, not specified, often Muslim. The often darker skinned women are often fully covered and do not produce any where enough Vitamin D during pregnancy or while breastfeeding. Without supplement the babies are at very high risk of deficiency. There are no reports of an increase in rickets among the fairer complected populations in Australia that I can find or have heard of.
Palms and soles are obvious places for melanoma in darker complected people because they have less protection (pigment) there.
I have no cites for the comments I have previously expressed; the are purely anecdotal and come exclusively from discussions I have had with my friends in Australia.
In this respect the links citing the incidence of rickets are interesting: it raises the question of the incidence of both rickets and skin cancers in the countries of origin of these immigrant people.
Seems to me that the countries cited in the posts above would have sunshine exposure very similar to Australia, so how do their affliction rates compare to Australia?
While I didn’t spend a lot of time looking for statistics, this link does provide some background for Australia: Slip-Slop-Slap - Wikipedia .
It says that: “since the “slip/slop” campaign was introduced , the incidence of the two most common forms of skin cancer (basal-cell carcinoma and squamous cell carcinoma) in Australia has decreased.”
It also says: “ … however, the incidence of melanoma - the most lethal form of skin cancer - has increased”.
I can’t help but wonder if there has been a cost/benefit analysis of the slip/slop campaign in Australia? Ie: what is the benefit of an an increase in lethal melanoma, verses a decrease in treatable skin cancers?
Also, what exactly constitutes “a huge health problem”? Are people dying the streets in Australia, or what?
In reading the posts above, I wonder how much of the problem in Australia is an imported problem, and how much of it is caused by local conditions and exposure to “native” Australians?
If it is an “imported” problem, maybe the slip/slop campaign is redundant and misdirected?
Read on. 430,000 people are treated for skin cancer each year, from a population of about 21 million.
Also this pdf, which was published in response to people increasing their sun exposure due to fears of vitamin D deficiency. It gives a cite that “Sun exposure is the cause of around 99% of non-melanoma skin cancers and 95% of melanomas in Australia”.
Pretty much. The population is predominantly pale skinned, and they spend more time outdoors than other similar populations. It’s not that the sun is worse here, or that people are abnormally susceptible to skin cancer.
There is evidence here that there is a specific relationship between malignant melanoma and the age of arrival in Australia.
Migrant children below the age of 10 years have equal risk to Australian-born; after age 15, incidences proved to be about 25%; any age after that showed no significant advantage.
Given that, it may be arguable that the “slip, slop, slap” campaign is of less use to anyone over the age of, say 20.
I think you’ll find that the amount of time spent outdoors has less significance in determining the likelihood of skin cancer of any type, than does having a history of repeated incidences of sunburn and skin damage.
I’m a little confused as to what these statistics are saying:
They are saying that if the person arrives in Australia after age 20(?), in terms of susceptibility to cancers, they are indistinguishable from the “native” Australians.
Does this mean that their prior exposure is equivalent to that of the “native” Australian?
This would not seem to be consistent with the statistics for the earlier two age groups; and would seem to imply that Australian sun exposure is not any more than that experienced by the immigrant in their native country.
Would this not imply that high incidences of cancer in Australia are due to some factor other than sun exposure?
And no; it is if a child arrives aged 10 and under that their susceptibility to cancers are indistinguishable from Australian-born. Arriving after age 15 gives a 75% less chance of developing skin cancer, and arriving at any later age gives no further advantage than this 75%.
The propensity for developing the various forms of skin cancer is formed in childhood exposure to the damaging rays. Later exposure, especially if extreme can increase the incidence in older people, but it’s not generally considered to be statistically significant.
My story is that I am now 51 years old, with a very pale skin that freckles. I grew up in a small town in southern Australia that was a summer-holiday mecca for people escaping from the city for a spell of surf, sand and sun.
When I was a child, the notion of protection was, well, pretty much unheard of…except for a blob of zinc cream over your nose if you felt like it. The only lotion that was applied to the body was ‘coconut oil’ which of course basted your body like a turkey in an oven. In those days there was NO notion of keeping your body safe from the sun.
The damage that I sustained in those early years, which included severe sunburns on MANY occasions, sometimes enough to confine me to bed for several days, have now come home to roost. I have had seven cancers removed, and another four are in the pipeline. None of them (thankfully) have been malignant, but that is not to say that future ones will be of the same ilk.
Things have changed now. My little grandson is not allowed outside without his hat. When at the beach, he wears a full-body protective suit AND sunscreen for those small bits that aren’t covered.
(bolding mine) I used to hear a lot about the ozone hole (or at any rate, ozone depletion) creeping over the southern side of the country and, yes, making the sun here worse as far as skin cancer is concerned.
Haven’t heard much about that in the last decade or so. Even though the “ozone hole” is still, AFAIK, there
