Teresa Pitman wrote:
> Okay, I don't understand this. If it's impossible to get enough
> Vitamin D from the sun, how did people survive all these generations?
>
Biologically, it's a 'new' issue.
We only left Africa approx 70 000 years ago. For much of that 70 000
years, Vit D wasn't a major issue, as we migrated very slowly, and our
skin (presumably) lightened to capture more Vit D from the weakening
sun, as we walked a bit, stayed put, had babies, walked a bit more. It
wasn't until we hit the very Northern Climes, with overcast skies much
of the year, and the need to wear clothing and shelter from the elements
all day long, that we ended up having to have exceptionally fair skins,
to capture as much Vitamin D as we possibly could.
We've only been into agriculture and towns and town living, for about 12
000 years. So we've only been able to survive in numbers from stored
food, in very cold climates, for about 6 - 8 000 years. Then we added in
transport, to move us about a lot, and then we worked on building the
sorts of homes we didn't like leaving, and in fact, only leave them to
work in buildings. Moving so fast that skin no longer adapted, is a
major problem - hence having dark skin in Northern climes means.. the
sun is too weak.
Biologically speaking, this is a very very new problem. Some areas of
the world, do have significant problems, such as Scotland, where they
are linking the highest MS rates in the world to chronic Vit D
deficiency. Scotland is cold, wet and windy much of the year. It has
overcast cloud cover for large parts of the year - part and parcel of
all that rain. It does not have a culture of being outdoors, bar for a
few weeks in the Summer, where, traditionally, you burn yourself red raw
as your skin as not touched natural daylight for the rest of the year.
Now, of course, the kids don't even get that, as they are slathered in
sun screen.
I'm pretty sure the more Northerly mainland European countries have less
of a problem with Vit D deficiency, as they have less cloud cover most
of the year, and light actually reflects off snow. Also, most of the
'snow' countries have an active tradition of getting out into it. The
UK is pretty dire about getting out and about: a sign of our massive
industrial expansion, no doubt.
Rickets from complete lack of sunshine at all, was common in UK
industrial slums in past generations. Coming back, as we only got out
into the sun for a very short sliver of time, culturally speaking.
And goodness knows what we've put into the sky, and how that affects
absorption.
Rickets has always been a problem whilst we've moved about - you can see
it in the bones records. But women with rickets didn't tend to birth,
as their pelvis twisting would hinder birthing. So severe rickets is
self-terminating. Since the Industrial revolution, they've also tended
to be the poorest women, stuck in factories in daylight hours. Which is
hilarious funny, as once only the rich, could be pale. Look at
classical art, and the most beautiful woman is always the one with ghost
white skin, highlighted as the palest of the pale. Everyone else worked
in the sun: pale skin was a sign of wealth and privilege. Until the
poor got to be pale, of course! Then you had to have a tan to be rich.
So, in terms of 'generations'.... modern travel and very large distance
migration is actually only 3-4 hundred years old, with most of it taking
place in the past 150 years. The culture of living and working
indoors, likewise.
Just like a lot of the foods we now eat, not having enough sunshine on
our skin, is pretty 'new' stuff for most of us. Biologically, a very
modern problem. And, of course, it's not impossible to get what you
need from the sun - if you have the right sun for the right skin and the
right lifestyle. But that requires _thinking_ about! We like quick
fixes, we humans. :-)
Also, when this debate is taking place, most people forget what the
'real' reason for wearing sun screen is for most people - especially
women. We like to bang on about it being for skin cancer, but that's
not actually correct. That's the reason we feel _safe_ in wearing it -
it's our 'protection from criticism' filter. The more pertinent reason
is vanity. Sun ages skin. I've worn sun screen on my face for over 25
years - and vanity is the reason, pure and simple. Originally, I wore
it all over, now I let the rest of my body have sun - even 'tho I hate
it. I like being pale and Gothic. But as for my face... I'm simply
vain about ageing. Next time you're talking to a woman about sun
screen... scratch the surface about why she's wearing it... ;-)
Morgan Gallagher
(Expecting a confrontation at Nursery any day now. My 4 year old does
not wear sunscreen, as I prefer to control the dangers of actually
burning, with shade and clothing, whilst actually letting THE SUN TOUCH
HIS SKIN! Currently, after a wonderful holiday in Fife, where THE SUN
came out, my 4 year old has a light touch of golden sun kiss. I'm
expecting Child Protection will be called any second now. ;-) )
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