Do we still get vitamin D from sunshine when we sit behind glass? © Getty Images

Do we still get vitamin D from sunshine when we sit behind glass?

More good reasons to take yourself outside and enjoy the sunshine.

Asked by: Jeff Hibbard, Birmingham

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No. Ordinary window glass is only transparent to wavelengths of light longer than 330 nanometres. But to synthesise vitamin D, we need UVB wavelengths between 270 and 300nm. You can get a suntan through glass, but to make vitamin D you need to be outside. On the other hand, at least 50 per cent of UVA can penetrate through glass, so skin ageing can still take place.


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