blue light than that of somebody with dark brown eyes.
Now, that doesn’ t mean that dark eyed people shouldn’ t be attentive to light exposure as well. It’ s very important that we get our light and darkness exposures right. I think most people have what we called in the article, darkness deficiency. And melatonin and vitamin D, truly in my view are like brother and sister. They work together, they’ re interrelated. Vitamin D is also considered a hormone.
Adrian: What’ s the app that you are referring to?
Deanna: Well, the one I have on my phone is called LightMeter. It’ s very easy to use. You have to point the camera of your phone as if your eyes were viewing in that direction.
When I work in front of a window the lux can be up to 5,000. But if I were working in front of a wall it might be 200.
Another thing, we just are coming off of a full moon. There was a very interesting study carried out in a sleep lab, with no windows, which found that melatonin production was lowest within four days either side of a full moon, perhaps suggesting the role of a lunar rhythm.
There’ s an idea about individual variation. I would call some people morning larks and others evening owls. There’ s a chronotype, and everybody’ s a little different. For an evening chronotype, an option would be to dim the lights, also, to use light sources with more red hues( like our pink salt lamp). White to blue light, notoriously the light of electronic device screens, deters production of melatonin by the pineal gland. So light sources like candlelight, fireplaces, light that is red and not blue, is an option for evenings. If you can’ t get to that red light, glasses that block blue light are an option. The nature of light entering the eyes is critical. The eyes are what are signalling to the brain to produce melatonin.
Adrian: Those glasses can vary quite a lot in price. Does it matter, in terms of price?
Deanna: They have all different kinds too. Like one of the ones that I wear during the day just to prevent too much blue light on my retinas. Because the eyes are part of the brain. and the eyes are what are signaling to the brain in order to produce melatonin, so I will wear a pair that has this iridescent look to it, so it’ s not red but it stops some of that blue light. And then there are other kinds of glasses where they have gradations of colour, like orange as it gets dim and then red for