Sun through glass

[hifi_dave]

On a lovely, sunny day like today, I have the urge to get some Sun on my skin to top up my vitamin-D but it's too cold to sit outside. My office is South facing so the Sun is beating down through the windows but do any good rays get through the glass ?

[Clifford.T Ward]

No you have to go outside......UVB; wavelengths of 290 to 315 nanometers stimulates the production of vitamin D3 from 7-dehydrocholesterol (7-DHC) in the epidermis of the skin and those rays are stopped by glass.

[Ali Tait]

Unless you are a ginger, in which case your body makes it's own. :-)

[hifi_dave]

No you have to go outside......UVB; wavelengths of 290 to 315 nanometers stimulates the production of vitamin D3 from 7-dehydrocholesterol (7-DHC) in the epidermis of the skin and those rays are stopped by glass.

Bugger. It's so nice and warm here, I was hoping it would help.

[Stryder5]

Bugger. It's so nice and warm here, I was hoping it would help.

If you go outside with warm clothes and goggles, like skiers, and sit in the sun with a white piece of A2 paper to reflect the light from below you will get a great tan on the lower part of your face.

Look at photos of skiers and you will see the wonderful results.

The goggles are to protect eyes from UV.

Always be safe. :eek:

[brian2957]

You'll just have to go for a walk Dave . The work will be there when you get back :)

[Macca]

Take a vitamin D supplement once a day after a meal. Costs next to nothing. You can't store vitamin D so you would need to be out in the sunshine for a few hours every day, ideally with more than your face exposed, to get what you need.

Since this is impossible in England supplements are the way to go.

As Ali says, Gingers and indeed Daywalkers will probably be okay regardless.

[struth]

And it should be vitimin D3 not D2.

[IslandPink]

Nope - as advice above.
( Optical Designer advice follows ) -
Also there is no significant UV in the sun at 30 degrees up from horizon ie. at this time of year at all. You don't get much until March or early April in the UK and then only around mid-day.
Sky & Telescope magazine about 20 years ago ran a very interesting article ( I cannot find it on the internet ) entitled 'The Physics of Suntanning' .
If you rate the UV level on the equator in summer ( sun overhead ) as 100% , the UV level, at best ( June 21st midday ) in the UK is 50% .
With the sun at 30 degrees , midday winter in the UK , the UV level is 1% .
(The UV transmission of the atmosphere varies as Cosec^2 (theta) and the extinction coefficient is quite high to begin with - hence the above numbers)

Ps. I have a roll-out sun canopy in the bedroom with UV-B tubes, it keeps me sane in the Winter !

[hifi_dave]

Thanks all for the advice. I will just have to wait for the Spring and get out in the Sunshine. It does make me feel better.

[Oddball]

I take Vit D3 every day , without fail in winter !
And I work outside:)