Can you absorb vitamin D through a window?

Asked by: 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.

Read more:

• Should I bother taking vitamin pills?
• Can sunlight through glass objects really cause house fires?

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