TEDxGlasgow
Richard Weller: Could the sun be good for your heart?
Richard Weller: Kunne solen være godt for ens hjerte?
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1,175,703 views
Vores kroppe får D vitamin fra solen, men som hudlæge Richard Weller foreslår, giver sollys måske et andet overraskende gode. Ny forskning af hans team viser at nitrogenmonoxid, en kemisk sender, der gemmes i kæmpe depoter i huden, kan frigives af UV lys, til stor fordel for blodtrykket og det kardiovaskulære system. Hvad betyder det? Jamen, det forklarer måske hvorfor skotter er mere syge end australiere …
Richard Weller - Dermatologist
Dermatologist Richard Weller wants to know: Why are Scots so sick? Full bio
Dermatologist Richard Weller wants to know: Why are Scots so sick? Full bio
Double-click the English transcript below to play the video.
00:16
So, before I became a dermatologist,
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Så, inden jeg blev hudlæge,
00:18
I started in general medicine,
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startede jeg i almen medicin,
00:21
as most dermatologists do in Britain.
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som de fleste hudlæger i England gør.
00:23
At the end of that time, I went off to Australia,
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Derefter tog jeg til Australien,
00:25
about 20 years ago.
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for cirka 20 år siden.
00:27
What you learn when you go to Australia
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Det man lærer når man tager til Australien
00:29
is the Australians are very competitive.
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er at asutraliere er utrolige konkurrencemennesker.
00:32
And they are not magnanimous in victory.
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Og de er ikke storsindede med deres sejr.
00:34
And that happened a lot:
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Og det skete ofte:
00:36
"You pommies, you can't play cricket, rugby."
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"I britter, I kan ikke spille cricket, rugby."
00:38
I could accept that.
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Det kunne jeg acceptere.
00:40
But moving into work --
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Men med hensyn til arbejde --
00:43
and we have each week what's called a journal club,
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og hver uge er der det der hedder en journal klub,
00:45
when you'd sit down with the other doctors
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hvor man sidder ned med de andre læger
00:48
and you'd study a scientific paper
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og gennemgår en videnskabelig artikel
00:50
in relation to medicine.
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relateret til medicin.
00:52
And after week one, it was about cardiovascular mortality,
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Og efter den første uge, handlede det om kardiovaskulær mortalitet,
00:54
a dry subject -- how many people die of heart disease,
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et tørt emne -- om hvor mange mennesker dør af hjertelidelser,
00:58
what the rates are.
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om hvad raten er.
01:00
And they were competitive about this:
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Og de var konkurrencemindede omrking dette:
01:01
"You pommies, your rates of heart disease are shocking."
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"I britter, jeres antal af hjertelidelser er chokerende."
01:05
And of course, they were right.
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Og selvfølgelig havde de ret.
01:06
Australians have about a third less heart disease than we do --
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Australiere har omkring en tredjedel færre hjertelidelser end vi har --
01:10
less deaths from heart attacks, heart failure, less strokes --
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færre dødsfald af hjerteanfald, hjerte fejl, færre slagtilfælde --
01:14
they're generally a healthier bunch.
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de er generelt set et sundere slæng.
01:16
And of course they said this was because of
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Og selvfølgelig sagde de at dette var på grund af
01:18
their fine moral standing, their exercise,
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deres gode moral, deres motion,
01:20
because they're Australians and we're weedy pommies, and so on.
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fordi de er australiere og vi er splejsede britter, og så videre.
01:24
But it's not just Australia that has better health than Britain.
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Men det er ikke kun Australien der har bedre helbred end England.
01:29
Within Britain, there is a gradient of health --
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Indenfor Storbritanien, er der grader af helbred --
01:33
and this is what's called standardized mortality,
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og det er det der hedder standardiseret mortalitet,
01:35
basically your chances of dying.
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som dybest set er ens chancer for at dø.
01:37
This is looking at data from the paper about 20 years ago,
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Her ser vi på data fra en artikel fra omkring 20 år siden,
01:40
but it's true today.
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men det er stadig sandt i dag.
01:42
Comparing your rates of dying 50 degrees north --
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Sammenlignet med ens rate for at dø 50 grader nord --
01:45
that's the South, that's London and places --
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det er syden, det er London og sådanne steder --
01:47
by latitude, and 55 degrees --
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i breddegrader, og 55 grader --
01:50
the bad news is that's here, Glasgow.
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de dårlige nyheder er, at her, Glasgow.
01:53
I'm from Edinburgh. Worse news, that's even Edinburgh.
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Jeg kommer fra Edinburgh. Dårligere nyt, det er selv Edinburgh.
01:55
(Laughter)
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(Latter)
02:00
So what accounts for this horrible space here
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Så hvad er det, der gør rede for dette forfærdelige sted her
02:03
between us up here in southern Scotland
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mellem os heroppe i det sydlige Skotland
02:05
and the South?
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og syden?
02:06
Now, we know about smoking,
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Men, vi kender til rygning,
02:08
deep-fried Mars bars, chips -- the Glasgow diet.
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dybfrosne Mars, chips -- Glasgow kosten.
02:10
All of these things.
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Alle disse ting.
02:12
But this graph is after taking into account
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Men denne graf tager hensyn til
02:14
all of these known risk factors.
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alle disse kendte risikofaktorer.
02:16
This is after accounting for smoking, social class, diet,
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Den tager hensyn til rygning, social klasse, kost,
02:20
all those other known risk factors.
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alle de kendte risikofaktorer.
02:22
We are left with this missing space
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Tilbage er dette manglende stykke
02:24
of increased deaths the further north you go.
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med et forhøjet dødsantal jo længere nordpå man kommer.
02:28
Now, sunlight, of course, comes into this.
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Men, sollys, selvfølgelig, kommer ind i dette.
02:31
And vitamin D has had a great deal of press,
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Og vitamin D har fået en masse presseomtale,
02:33
and a lot of people get concerned about it.
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og mange mennesker er bekymret over det.
02:35
And we need vitamin D. It's now a requirement that children have a certain amount.
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Og vi har brug for D vitamin. Det er nu et krav at børn får en bestemt mængde.
02:39
My grandmother grew up in Glasgow,
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Min bedstemor voksede op i Glasgow,
02:41
back in the 1920s and '30s when rickets was a real problem
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tilbage i 1920'erne og 30'erne da rakitis var et virkeligt problem
02:45
and cod liver oil was brought in.
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og torske-levertran blev introduceret.
02:47
And that really prevented the rickets that used to be common in this city.
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Og det afværgede virkelig rakitis der plejede at være almindeligt i byen.
02:51
And I as a child was fed cod liver oil by my grandmother.
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Og som barn blev jeg fodret med torske-levertran af min bedstemor.
02:55
I distinctly -- nobody forgets cod liver oil.
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Jeg husker tydeligt -- ingen glemmer torske-levertran.
02:58
But an association: The higher people's blood levels of vitamin D are,
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Men en association: Jo højere menneskers indhold af D vitamin i blodet er,
03:03
the less heart disease they have, the less cancer.
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jo færre hjertelidelser har der, mindre kræft.
03:06
There seems to be a lot of data suggesting that vitamin D is very good for you.
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Det lader til, at der er meget data, der antyder at D vitamin er meget sundt for en.
03:10
And it is, to prevent rickets and so on.
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Og det er det, for at forhindre rakitis og så videre.
03:12
But if you give people vitamin D supplements,
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Men hvis man giver mennesker D vitamn tilskud,
03:15
you don't change that high rate of heart disease.
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ændrer man ikke den høje rate af hjertelidelser.
03:18
And the evidence for it preventing cancers is not yet great.
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Og beviset på at det forhindrer kræft er endnu ikke overbevisende.
03:22
So what I'm going to suggest is that vitamin D is not the only story in town.
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Så det jeg vil foreslå er at D vitamin ikke er den eneste historie i byen.
03:27
It's not the only reason preventing heart disease.
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Det er ikke den eneste grund der forhindrer hjertelidelser.
03:30
High vitamin D levels, I think, are a marker for sunlight exposure,
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Høje D vitamin niveauer, tror jeg, er en markør for eksponering for sollys,
03:35
and sunlight exposure, in methods I'm going to show,
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og eksponering for sollys, på de måder som jeg vil vise,
03:38
is good for heart disease.
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er godt for hjertelidelser.
03:40
Anyway, I came back from Australia,
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Hvorom alt er, jeg kom tilbage fra Australien,
03:42
and despite the obvious risks to my health, I moved to Aberdeen.
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og på trods af de åbenlyse ricisi imod mit helbred, flyttede jeg til Aberdeen.
03:46
(Laughter)
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(Latter)
03:48
Now, in Aberdeen, I started my dermatology training.
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Så, i Aberdeen startede jeg min dermatolog uddannelse.
03:51
But I also became interested in research,
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Men jeg blev også interesseret i forskning,
03:53
and in particular I became interested in this substance, nitric oxide.
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og jeg blev især interesseret i denne substans, nitrogenmonoxid.
03:56
Now these three guys up here,
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Så disse fyre heroppe,
03:58
Furchgott, Ignarro and Murad,
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Furchgott, Ignarro og Murad,
03:59
won the Nobel Prize for medicine back in 1998.
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vandt Nobel prisen i medicin tilbage i 1998.
04:03
And they were the first people to describe
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Og de var de første mennesker til at beskrive
04:05
this new chemical transmitter, nitric oxide.
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denne nye kemiske sender, nitrogenmonoxid.
04:08
What nitric oxide does is it dilates blood vessels,
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Det nitrogenmonoxid gør er, at det udvider blodkarene,
04:11
so it lowers your blood pressure.
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så det sænker ens blodtryk.
04:13
It also dilates the coronary arteries, so it stops angina.
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Det udvider også hjerte pulsårene, så det stopper hjertekrampe.
04:17
And what was remarkable about it
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Og det der var bemærkelsesværdigt ved det
04:19
was in the past when we think of chemical messengers within the body,
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var at da vi før i tiden tænkte på kemiske sendere i kroppen,
04:23
we thought of complicated things like estrogen and insulin,
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tænkte vi på komplicerede ting som østrogen og insulin,
04:26
or nerve transmission.
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eller nerve transmission.
04:27
Very complex processes with very complex chemicals
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Meget komplekse processer med meget komplekse kemikalier
04:31
that fit into very complex receptors.
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det passer ind i meget komplekse receptorer.
04:33
And here's this incredibly simple molecule,
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Og her er dette utrolig simple molekule,
04:35
a nitrogen and an oxygen that are stuck together,
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et nitrogen og et oxygen der er sat sammen,
04:39
and yet these are hugely important for [unclear] our low blood pressure,
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og alligevel er disse utrolig vigtige for [utydeligt] vores lave blodtryk,
04:43
for neurotransmission, for many, many things,
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for neurotransmission, for mange, mange ting,
04:46
but particularly cardiovascular health.
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men i særdeleshed for vores kardiovaskulære helbred.
04:49
And I started doing research, and we found, very excitingly,
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Og jeg begyndte at forske, og vi fandt ud af, meget spændende,
04:53
that the skin produces nitric oxide.
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at huden producerer nitrogenmonoxid.
04:55
So it's not just in the cardiovascular system it arises.
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Så det er ikke kun i det kardiovaskulære system at det opstår.
04:58
It arises in the skin.
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Det opstår i huden.
05:00
Well, having found that and published that,
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Jamen, efter at have fundet det og udgivet det,
05:02
I thought, well, what's it doing?
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tænkte jeg, jamen, hvad gør det?
05:04
How do you have low blood pressure in your skin?
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Hvordan har man et lavt blodtryk i huden?
05:05
It's not the heart. What do you do?
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Det er ikke hjertet. Hvad gør man?
05:07
So I went off to the States, as many people do if they're going to do research,
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Så jeg tog til staterne, som mange mennesker gør hvis de vil lave forskning,
05:11
and I spent a few years in Pittsburgh. This is Pittsburgh.
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og jeg tilbragte et par år i Pittsburgh. Dette er Pittsburgh.
05:15
And I was interested in these really complex systems.
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Og jeg var interesseret i disse meget komplekse systemer.
05:18
We thought that maybe nitric oxide affected cell death,
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Vi tænkte at nitrogenmonoxid måske påvirkede celledød,
05:22
and how cells survive, and their resistance to other things.
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og hvordan celler overlever, og deres modstand overfor andre ting.
05:24
And I first off started work in cell culture, growing cells,
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Og jeg begyndte - som det første - at arbejde med celle kulturer - at dyrke celler,
05:28
and then I was using knockout mouse models --
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og så brugte jeg hammerlækre musemodeller --
05:30
mice that couldn't make the gene.
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mus der ikke kunne lave genet.
05:32
We worked out a mechanism, which -- NO was helping cells survive.
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Vi udarbejdede en mekaniske, hvor -- nitrogenmonoxid hjalp cellerne med at overleve.
05:36
And I then moved back to Edinburgh.
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Og så flyttede jeg tilbage til Edinburgh.
05:40
And in Edinburgh, the experimental animal we use is the medical student.
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Og i Edinburgh er det eksperimentelle dyr vi bruger de medicinstuderende.
05:43
It's a species close to human,
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Det er en art tæt på mennesker,
05:45
with several advantages over mice:
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med adskillige fordele i forhold til mus:
05:47
They're free, you don't shave them, they feed themselves,
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De er gratis, man barberer dem ikke, de fodrer sig selv,
05:50
and nobody pickets your office saying,
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og ingen strejker ude foran ens kontor med,
05:52
"Save the lab medical student."
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"Red de forsøgs-medicinstuderende."
05:55
So they're really an ideal model.
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Så de er faktisk en ideel model.
05:58
But what we found
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Men det vi fandt ud af
06:00
was that we couldn't reproduce in man the data we had shown in mice.
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var at vi i et menneske ikke kunne reproducere de data vi havde vist i mus.
06:04
It seemed we couldn't turn off the production
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Det virkede som om at vi ikke kunne slukke for produktionen
06:08
of nitric oxide in the skin of humans.
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af nitrogenmonoxid i menneskers hud.
06:11
We put on creams that blocked the enzyme that made it,
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Vi puttede creme på, der blokkerede det enzym der producerer det,
06:13
we injected things. We couldn't turn off the nitric oxide.
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vi indsprøjtede ting. Vi kunne ikke slukke for nitrogenmonoxiden.
06:18
And the reason for this, it turned out, after two or three years' work,
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Og grunden til dette, viste det sig, efter to eller tre års arbejde,
06:21
was that in the skin we have huge stores
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var at vi i huden har kæmpestore depoter
06:25
not of nitric oxide, because nitric oxide is a gas,
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ikke af nitrogenmonoxid, fordi nitrogenmonoxid er en gas,
06:28
and it's released -- (Poof!) -- and in a few seconds it's away,
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og den bliver udløst -- (Poof!) -- og efter få sekunder er den væk,
06:31
but it can be turned into these forms of nitric oxide --
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men den kan ændres til disse former for nitrogenmonoxid --
06:35
nitrate, NO3; nitrite, NO2; nitrosothiols.
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nitrat, NO3; nitrit, NO2; nitrotioler.
06:38
And these are more stable,
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Og de er mere stabile,
06:40
and your skin has got really large stores of NO.
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og ens hud har virkelig store depoter af nitrogenmonoxid.
06:44
And we then thought to ourselves, with those big stores,
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Og så tænkte vi for os selv, med de store depoter,
06:47
I wonder if sunlight might activate those stores
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gad vide om sollys aktiverer de depoter
06:50
and release them from the skin,
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og frigør dem fra huden,
06:52
where the stores are about 10 times as big as what's in the circulation.
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hvor depoterne er omkring 10 gange så store, som det der er i cirkulation.
06:55
Could the sun activate those stores into the circulation,
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Kunne solen aktivere de depoter til cirkulationen,
06:58
and there in the circulation do its good things for your cardiovascular system?
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og der - i cirkulationen - gøre gode ting for ens kardiovaskulære system?
07:03
Well, I'm an experimental dermatologist,
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Jamen, jeg er eksperimentel dermatolog,
07:06
so what we did was we thought
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så det vi gjorde var, at vi tænkte
07:07
we'd have to expose our experimental animals to sunlight.
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at vi skulle udsætte vores forsøgsdyr for sollys.
07:11
And so what we did was we took a bunch of volunteers
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Så det vi gjorde var, at vi tog en stak frivillige
07:15
and we exposed them to ultraviolet light.
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og vi udsatte dem for ultraviolet lys.
07:17
So these are kind of sunlamps.
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Så dette er en slags sollamper.
07:19
Now, what we were careful to do was,
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Så, det vi var forsigtige med at gøre var,
07:22
vitamin D is made by ultraviolet B rays
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D vitamin er lavet af ultraviolette B stråler
07:25
and we wanted to separate our story from the vitamin D story.
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og vi ville separere vores historie fra D vitamin historien.
07:29
So we used ultraviolet A, which doesn't make vitamin D.
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Så vi brugte ultraviolet A, som ikke laver D vitamin.
07:33
When we put people under a lamp
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Da vi satte mennesker under en lampe
07:35
for the equivalent of about 30 minutes of sunshine in summer in Edinburgh,
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til det der svarede til 30 minutters sollys om sommeren i Edinburgh,
07:40
what we produced was, we produced a rise
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det vi frembragte var, vi frembragte en stigning
07:42
in circulating nitric oxide.
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i den cirkulerende nitrogenmonoxid.
07:44
So we put patients with these subjects under the UV,
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Så vi satte patienter sammen med disse forsøgspersoner under en UV lampe,
07:47
and their NO levels do go up,
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og deres nitrogenmonoxid niveauer stiger,
07:50
and their blood pressure goes down.
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og deres blodtryk falder.
07:52
Not by much, as an individual level,
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Ikke med meget, på et individuelt niveau,
07:54
but enough at a population level
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men nok på befolknings niveau
07:57
to shift the rates of heart disease in a whole population.
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til at flytte raterne på hjertelidelse i hele befolkningen.
08:00
And when we shone UV at them,
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Og når vi skinnede UV stråler på dem,
08:03
or when we warmed them up to the same level as the lamps,
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eller når vi varmede dem op til samme niveau som lamperne,
08:06
but didn't actually let the rays hit the skin, this didn't happen.
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men faktisk ikke lod strålerne ramme huden, skete dette ikke.
08:10
So this seems to be a feature of ultraviolet rays hitting the skin.
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Så det ser ud til at være en egenskab ved ultraviolette stråler der rammer huden.
08:14
Now, we're still collecting data.
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Men, vi indsamler stadig data.
08:15
A few good things here:
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Et par gode ting her:
08:17
This appeared to be more marked in older people.
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Dette lod til at være mere markant hos ældre mennesker.
08:20
I'm not sure exactly how much.
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Jeg er ikke sikker på præcis hvor meget.
08:22
One of the subjects here was my mother-in-law,
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En af forsøgspersonerne her var min svigermor,
08:23
and clearly I do not know her age.
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og jeg kender selvfølgelig ikke hendes alder.(latter)
08:26
But certainly in people older than my wife,
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Men hos mennesker, der er ældre end min kone,
08:30
this appears to be a more marked effect.
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ser dette ud til at have en mere markant effekt.
08:33
And the other thing I should mention
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Og den anden ting jeg bør nævne
08:34
was there was no change in vitamin D.
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er, at der ikke var nogen ændring i D vitaminet.
08:36
This is separate from vitamin D.
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Dette er separat fra D vitamin.
08:38
So vitamin D is good for you -- it stops rickets,
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Så D vitamin er godt for en -- det stopper rakitis,
08:40
it prevents calcium metabolism, important stuff.
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det forhindrer kalcium metabolisme, vigtige ting.
08:42
But this is a separate mechanism from vitamin D.
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Men dette er en separat mekanisme fra D vitaminet.
08:45
Now, one of the problems with looking at blood pressure
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Men, et af problemerne ved at se på blodtrykket
08:48
is your body does everything it can
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er at ens krop gør alt hvad den kan
08:49
to keep your blood pressure at the same place.
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for at holde ens blodtryk på det samme niveau.
08:51
If your leg is chopped off and you lose blood,
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Hvis ens ben bliver hugget af og man mister blod,
08:52
your body will clamp down, increase the heart rate,
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vil ens krop spænde sig, sætte pulsen op,
08:55
do everything it can to keep your blood pressure up.
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gøre alt hvad den kan for at holde ens blodtryk oppe.
08:58
That is an absolutely fundamental physiological principle.
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Det er et absolut fundamentalt fysiologisk princip.
09:01
So what we've next done
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Så det vi gjorde bagefter
09:02
is we've moved on to looking at blood vessel dilatation.
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er at vi begyndte på at kigge på udvidelsen af blodkarene.
09:06
So we've measured -- this is again,
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Så vi har målt -- dette er igen,
09:08
notice no tail and hairless, this is a medical student.
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læg mærke til ingen hale og ingen hår. Dette er en medicinstuderende.
09:13
In the arm, you can measure blood flow in the arm
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I armen, kan man måle blod gennemstrømningen
09:15
by how much it swells up as some blood flows into it.
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ved hvor meget den svulmer op, når der flyder noget blod i den.
09:19
And what we've shown is that doing a sham irradiation --
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Og det vi har vist er, at lave en falsk bestråling --
09:22
this is the thick line here --
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det er denne tykke linje her --
09:24
this is shining UV on the arm so it warms up
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den skinner UV på armen så den varmes op
09:26
but keeping it covered so the rays don't hit the skin.
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men holdes dækket, så strålerne ikke rammer huden.
09:29
There is no change in blood flow, in dilatation of the blood vessels.
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Der er ikke nogen ændring i blodgennemstrømningen, eller i udvidelsen af blodkarene.
09:33
But the active irradiation,
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Men den aktive stråling,
09:35
during the UV and for an hour after it,
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i løbet af UV og i en time derefter,
09:38
there is dilation of the blood vessels.
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er der en udvidelse af blodkarene.
09:40
This is the mechanism by which you lower blood pressure,
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Dette er mekanismen hvormed man sænker blodtrykket,
09:43
by which you dilate the coronary arteries also,
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hvormed man også udvider hjerte pulsårene,
09:45
to let the blood be supplied with the heart.
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for at lade blodet blive forsynet til hjertet.
09:47
So here, further data that ultraviolet -- that's sunlight --
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Så her, mere data, at ultraviolet -- det er sollys --
09:51
has benefits on the blood flow and the cardiovascular system.
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har fordele for blodgennemstrømningen og det kardiovaskulære system.
09:56
So we thought we'd just kind of model --
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Så vi tænkte at vi ville lave en model --
09:58
Different amounts of UV hit different parts of the Earth at different times of year,
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Forskellige mængder UV rammer forskellige dele af jorden på forskellige tider af året,
10:05
so you can actually work out those stores of nitric oxide --
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så man kan faktisk træne de nitrogenmonoxid depoter --
10:09
the nitrates, nitrites, nitrosothiols in the skin --
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nitraterne, nitriterne, nitrosotiolerne i huden --
10:11
cleave to release NO.
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bane sig vej for at frigive NO.
10:14
Different wavelengths of light have different activities of doing that.
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Forskellige bølgelængder af lys har forskellige måder at gøre det ved.
10:18
So you can look at the wavelengths of light that do that.
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Så man kan se på bølgelængderne af lys der gør det.
10:20
And you can look -- So, if you live on the equator, the sun comes straight overhead,
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Og man kan se -- Så, hvis man bor på ækvator, kommer solen lige ovenover hovedet,
10:24
it comes through a very thin bit of atmosphere.
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den kommer gennem et meget tyndt lag atmosfære.
10:25
In winter or summer, it's the same amount of light.
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I vinter eller sommer, er det den samme mængde lys.
10:28
If you live up here, in summer
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Hvis man lever heroppe, om sommeren
10:30
the sun is coming fairly directly down,
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kommer solen temmelig direkte ned,
10:33
but in winter it's coming through a huge amount of atmosphere,
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men om vinteren kommer den igennem en kæmpe mængde atmosfære,
10:36
and much of the ultraviolet is weeded out,
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og meget af det ultraviolette bliver siet fra,
10:40
and the range of wavelengths that hit the Earth
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og rækkeviden af bølgelængderne der rammer jorden
10:42
are different from summer to winter.
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er forskellige om vinteren og sommeren.
10:44
So what you can do is you can multiply those data
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Så det man kan gøre er, at man kan gange den data
10:46
by the NO that's released
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med den NO der er frigivet
10:48
and you can calculate how much nitric oxide
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og man kan beregne hvor meget nitrogenmonoxid
10:51
would be released from the skin into the circulation.
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der ville blive løsladt fra huden ind i cirkulation.
10:55
Now, if you're on the equator here --
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Men, hvis man er på ækvator her --
10:57
that's these two lines here, the red line and the purple line --
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det er de to linjer her, den røde linje og den lila linje --
11:00
the amount of nitric oxide that's released is the area under the curve,
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mængden af nitrogenmonoxid der bliver frigivet er området under kurven,
11:04
it's the area in this space here.
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det er området i dette mellemrum her.
11:06
So if you're on the equator, December or June,
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Så hvis man er på ækvator, december eller juni,
11:09
you've got masses of NO being released from the skin.
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der er masser af NO der bliver frigivet fra huden.
11:12
So Ventura is in southern California.
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Så Ventura ligger i det sydlige Californien.
11:15
In summer, you might as well be at the equator.
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Om sommeren, man kunne lige så vel være på ækvator.
11:17
It's great. Lots of NO is released.
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Det er fedt. Der bliver frigivet masser af NO.
11:19
Ventura mid-winter, well, there's still a decent amount.
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Ventura midt om vinteren, jamen, der er stadig en pæn mængde.
11:23
Edinburgh in summer, the area beneath the curve is pretty good,
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Edinburgh om sommeren, området under curven er temmelig godt,
11:27
but Edinburgh in winter, the amount of NO that can be released
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men i Edinburgh om vinteren, er mængden af NO der kan blive frigivet
11:31
is next to nothing, tiny amounts.
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nærmest ingenting, bittesmå mængder.
11:35
So what do we think?
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Så hvad mener vi?
11:37
We're still working at this story,
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Vi arbejder stadig på denne historie,
11:38
we're still developing it, we're still expanding it.
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vi udvikler den stadig, vi udvider den stadig.
11:40
We think it's very important.
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Vi mener det er meget vigtigt.
11:42
We think it probably accounts for a lot of the north-south health divide within Britain,
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Vi mener det sandsynligvis forklarer meget af helbreds- skellet af nord og syd indenfor Storbritannien.
11:46
It's of relevance to us.
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Det er relevant for os.
11:47
We think that the skin --
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Vi mener at huden --
11:49
well, we know that the skin has got very large stores
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jamen, vi ved at huden har meget store depoter
11:52
of nitric oxide as these various other forms.
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af nitrogenmonoxid ved disse andre forskellige former.
11:54
We suspect a lot of these come from diet,
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Vi mistænker at meget af det kommer fra kosten,
11:56
green leafy vegetables, beetroot, lettuce
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grønne bladrige grøntsager, rødbeder, salat
11:58
has a lot of these nitric oxides that we think go to the skin.
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har mange af disse nitrogenmonoxider som vi mener går til huden.
12:02
We think they're then stored in the skin,
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Vi mener at de bliver opbevaret i huden,
12:04
and we think the sunlight releases this
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og vi mener at sollyset frigiver dette
12:06
where it has generally beneficial effects.
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hvor det generelt set har gavnlige effekter.
12:09
And this is ongoing work, but dermatologists --
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Og dette er løbende arbejde, men dermatologer --
12:11
I mean, I'm a dermatologist.
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Jeg mener, jeg er dermatolog.
12:13
My day job is saying to people, "You've got skin cancer,
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Mit almindelige arbejde er at sige til mennesker, "Du har hudkræft,
12:15
it's caused by sunlight, don't go in the sun."
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det er forårsaget af sollys, gå ikke ud i solen."
12:17
I actually think a far more important message
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Jeg mener faktisk at et meget vigtigere budskab
12:20
is that there are benefits as well as risks to sunlight.
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er at der er fordele lige så vel som risici ved sollys.
12:23
Yes, sunlight is the major alterable risk factor for skin cancer,
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Ja, sollys er den store justerbare risicofaktor for hudkræft,
12:29
but deaths from heart disease are a hundred times higher
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men antallet af døde af hjertelidelser er hundrede gange højere
12:32
than deaths from skin cancer.
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end antallet af døde af hudkræft.
12:34
And I think that we need to be more aware of,
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Og jeg mener at vi skal være mere klar over,
12:37
and we need to find the risk-benefit ratio.
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at vi har brug for at finde risiko-gavn raten.
12:39
How much sunlight is safe,
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Hvor meget sollys er sikkert,
12:40
and how can we finesse this best for our general health?
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og hvordan kan vi optimere dette på den bedste måde for vores generelle helbred?
12:44
So, thank you very much indeed.
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Så, bestemt mange tak.
12:47
(Applause)
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(Bifald)
ABOUT THE SPEAKER
Richard Weller - DermatologistDermatologist Richard Weller wants to know: Why are Scots so sick?
Why you should listen
Edinburgh-native Richard Weller was studying medicine in Australia when something suddenly struck him as odd: Why are the Scots so sick? Australians suffer from heart disease at one-third the rate that Britons do, with lower death rates from heart attacks and heart failure, and fewer strokes overall. When Weller looked into it, this wasn't unique to Australia and England: In fact, there are wide gaps in mortality even within the UK, a gradient which maps roughly ... geographically? A five-degree change in latitude -- between London and Edinburg, for example -- shows a nearly 20 percent higher rate of mortality. Weller and his team have been working ever since to crack this mysterious gap, and most recently their research shows it may be related to exposure to sunlight. Nitric oxide (NO), a chemical transmitter produced by the skin and stored in great reserves, is released by exposure to UV rays, and this in turn is very important to cardiovascular health.
Weller is a senior lecturer in Dermatology at the University of Edinburgh. His two areas of study are the role of NO in human skin physiology and the role of skin barrier function deficiencies in atopic disease.
Richard Weller | Speaker | TED.com