This is The Guardian.

Imagine coming home. You're expecting to see your partner or your mum or dad, but sitting in

the dark is a figure you don't quite recognise.

White masks over their face, an unearthly red glow coming from below,

dark holes where their mouth and eyes should be.

It sounds like something from a horror movie.

But it's actually the latest trend in our age-old quest to look younger for longer.

Red light therapy has been around for decades, but until recently it was only available

in expensive dermatology clinics.

That's all changing, thanks to an explosion in the range of devices you can use at home.

So today, what's the science behind red light therapy? And do these at home devices actually do anything?

From The Guardian, I'm Ian Sampo, and this is Science Weekly.

Maddie, Red Light Therapy Masks have become all the rage.

I basically had to run from someone in John Lewis the other day who was attempting to get me to

try one on. So look, to start

off, what is red light therapy? So this is the idea that shining red light on yourself is going

to have some kind of health or aesthetic benefit. So let's think about the electromagnetic spectrum.

Starting with UV, which is short wavelengths, then you go into the electromagnetic spectrum. Starting with UV, which is short wavelengths,

then you go into the visible spectrum and you're going to have the short wavelengths of visible

light. That's blue and purple. And then as the wavelengths get longer, think of the rainbow,

you go yellow, orange, red. So red has the longest wavelengths that we can see.

And after that, you go into infrared.

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