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
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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Authors
Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.
