But isn’t the link between sunbathing and cancer common
sense? Well yes, it is, but not necessarily right.
In 1975, faced with 30 years of increasing rates of skin cancer,
the State Government of Queensland in Australia followed the
medical establishment common sense link between sunbathing and
skin cancer, and embarked on a massive campaign to raise their
citizens’ awareness of the dangers. At first it appeared
to be hugely successful. People quickly accepted that exposure
to the sun could give them skin cancer. High-factor sun screens
were slapped onto every inch of skin whenever they left the
house. If children were even allowed outside they were dressed
in long-armed T-shirts, long trousers, socks and hats. The sun
screen on their hands and faces was renewed every hour.
Sunbathing and sun tans became unfashionable. Pasty white was
the new bronze, but there was a problem. Someone noticed that
the rate of malignant melanoma, the most serious, often fatal,
skin cancer, had not fallen but doubled during the ten years
since the campaign began, and that the rate in children had
risen to its highest ever, 30 cases per million, seven times
that in Europe. Furthermore, rickets had made a big come back,
as had all the other illnesses linked to vitamin D deficiency,
including breast and prostate cancers, multiple sclerosis and
type 1 diabetes.
Revised and re-issued in 1988, Australia's Cancer Council's
‘Sun Smart’ guidelines urged Australians to show
a little skin as described above, but with no effect. Most Aussies
are still paranoid about the sun. Even so, nearly all of the
sunbathers you see on Bondi Beach are still foreign tourists.
Vitamin D
Adequate levels of vitamin D are essential to many body functions,
which is why vitamin D deficiency has been linked to so many
illnesses, from osteomalacia (rickets) and high blood pressure
to colon, breast, prostate and ovarian cancer, multiple sclerosis
and type 1 diabetes. It can be acquired through food or a food
supplement, but the best way is by exposing your skin and eyes
to direct sunlight, at least during the summer months.
From late Spring to early Autumn, in sunny Cyprus or San Francisco,
for instance, 30 minutes exposure of the face and arms is sufficient
to produce enough vitamin D for several days. In countries further
north or south of the 30° latitude lines, where the angle
of sunlight is more oblique, at least 45 minutes is required.
From mid Autumn to mid Spring, as the angle of sunlight becomes
more oblique, more exposure is needed. In countries within 30°
of the equator 45 minutes to an hour is necessary. In countries
further from the equator, no amount of exposure can generate
sufficient vitamin D. Maximising vitamin D-rich foods,* or taking
a vitamin D supplement is necessary. Two thirds of Britons fail
to do this and are vitamin D-deficient by the end of their cold,
grey winter.
N.B. The exposure to the ultraviolet rays in sunlight must
be direct, not through glass. This means venturing outside,
not taking the car for a stroll, and not wearing sunglasses.
How much vitamin D do I need?
The UK Department of Health’s recommended dietary allowance
(RDA) is five micrograms or 200 international units (i.u.) a
day. The human body thinks it needs much more. Given enough
ultraviolet light on the skin and eyes, it produces 500 micrograms
a day for itself. Even more amazingly, it keeps the level of
new vitamin D at 500 micrograms. Any excess produced is destroyed!
No-one yet knows why, but zoologists do know that Nature never
designs such complex systems without good reason. Why is there
such a big difference? RDAs were first set during World War
II by the US National Academy of Sciences as guidelines for
keeping soldiers alive. The body is interested in achieving
the best possible health.
Sun screens
When there is a sudden unexpected epidemic of some illness,
particularly of a new illness, scientists quite rightly look
for changes in lifestyle which have developed over the same
period. Sometimes the link they make is spot on. Sometimes another
equally plausible link is missed. Here, the huge rise in sunbathing
and the two week bronzing blitz abroad were the common sense
links.
It looks like no-one in the scientific establishment, and certainly
no scientist employed by cosmetics manufacturers, ever chose
to note that the use of sun lotions and sun screens had also
soared. Could it be not only sun screens’ ultraviolet
light-blocking ability, but also the many chemicals they contain,
that are the main problems?
The skin is the body’s largest organ. It absorbs up to
60% of anything spread on it. Most sun lotions and sun screens
contain chemicals which are thought to increase the risk of
cancer. These include:
psoralen Now restricted to one part
per billion in sun screens following the finding that fair skinned
people who used sun screens containing psoralen ran a fourfold
risk of melanoma
para-aminobenzoic acid (PABA) Damages
DNA, increasing the risk of skin cancer
titanium dioxide Thought to be cancer-causing,
and now used in its more toxic nanoparticle form
six other UVB screening chemical compounds
which all made cancer cells grow rapidly in laboratory tests
What to do?
The UK Department of Health recommends against sun screens because
many only protect against burning, not against skin cancer,
and people think that they can stay in the sun longer. Green
Health Watch agrees, but also because of the dangerous chemicals
most sun screens contain. In our view, they should only be used
when absolutely essential. This goes especially for children,
whose smaller body sizes and weights make any toxic chemicals
their skin absorbs even more damaging.
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Clare Kitchen. Daily Mail