Can you absorb vitamin D through a window?

Sunday 6th June 2010
Submitted by Luis Villazon
Steven Collins, by E-mail

You don’t absorb vitamin D from the Sun, your skin synthesises it in response to sunlight. It’s the UVB portion of the ultra-violet spectrum that’s needed. This wavelength range is effectively blocked by glass so you can become deficient in vitamin D if you don’t go out and don’t eat enough oily fish or dairy products to compensate.

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