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.

GOT A QUESTION?

Scratching your head over a burning scientific conundrum? submit your question and we'll get our esteemed panel of experts to answer it for you.

 

Does microwaving food destroy its nutritional content?
previous qanda Article
Why are sunsets red?
next qanda Article
Q&A Tabs

Your DNA is arranged into chromosomes, which are grouped into 23 pairs. When a sperm cell is manufactured, the father’s genome is split in two, so that each sperm receives one chromosome...

A lunar month is slightly shorter than a calendar month, so every two to three years, there is an extra lunar cycle above the usual 12. This additional moon is called the ‘blue moon’...

We tend to think of the Sun as the stationary heart of our Solar System, with the planets orbiting serenely around it. In reality, the Sun is dragging us around the galaxy at around 800,000km/h,...

Hibernation is a response to cold weather and reduced food availability. Most animals that hibernate are quite small and, as the weather gets colder, they reach the point where they simply can...

Both are types of experimental engine designed for speeds greater than that of sound, in the hypersonic realm. They are jet engines with no moving parts, relying on the enormous pressures created...

All female mammals have a clitoris, the sole purpose of which is to react to sexual stimulation, and presumably this stimulation has evolved to be pleasurable for most species. But establishing...

To create a sound, we have to set matter - whether it's a gas like air, a liquid or even a solid material - in regular motion, creating a wave of specific frequencies, which we hear as a sound of...

Mirrors don’t reverse left and right either – that’s just our interpretation of what happens. Your reflection in the mirror is actually reversed front to back – if you have...

Discovered by an American student named Gary Flandro in the mid-1960s, the slingshot manoeuvre usually involves spacecraft briefly 'coat-tailing' a planet orbiting the Sun, extracting some of the...

The ice disappears because the wind blows away water molecules that have evaporated or 'sublimed' from the ice, so the ice slowly shrinks in size. The molecules that escape are those with the...

We use cookies to improve your experience of our website. Cookies perform functions like recognising you each time you visit and delivering advertising messages that are relevant to you. Read more here