Once you listen to this podcast, you'll be getting outside earlier in the day, spending more time outside, you'll feel better about the gloom of winter where you are right now, and you'll be doing all sorts of other things with light.

I thought I knew how important light was to our hormones, circadian rhythm and more.

But I was inspired and learnt so much in this podcast.

Roudy is the Founder and Head of Research and Development at VivaRays, an innovative firm with glasses transforming the way in which people work, sleep and live. Drawing on his own experiences and background in engineering, Roudy has designed a range of glasses for part of the day, blocking specific wavelengths.

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