When it comes to making sure we have an optimally functioning circadian rhythm we typically get drawn to blue light glasses as the one stop shop for giving you the perfect biological rhythms. This is only partially true. Whilst it is imperative that we block blue and green light entering the eye from direct sources after dark, this is only half of the solution to the problem.
It now appears that our skin, brain and even fat cells are sensitive to blue and green light and can critically unbalance our biological rhythms. The key component to the Jack Kruse coined phrase “Skin in the Game” is MELANOPSIN.
What is Melanopsin?
Melanopsin was found to be in our eye in 1998. Melanopsin is a type of photopigment belonging to a larger family of light-sensitive retinol proteins called opsins. Melanopsin is particularly sensitive to the absorption of blue light and will communicate these light frequencies to the central clock and peripheral oscillator clocks. Basically, Melanopsin is the key driver in setting of our circadian rhythms.
From the perspective of the eye when melanopsin regulates the amount of melatonin released from the pineal gland. Melatonin is essential for sleep and the most powerful antioxidant we can get. Therefore, it is important not to allow blue light to enter the eye after dark. Melanopsin is found primarily in the intrinsically photosensitive retinal gangliuon cells (ipRGCs). IpRGC receptors are in the inner retina and are only truly influenced by light from a direct head on source. Any small amount of peripheral light that enters the eye from the sides of your blue light blocking glasses is not enough to allow for a pupillary light reflex to phototransduct at a level required to activate melanopsin and supress melatonin.
It’s not just in the Eyes!
Until 2017 we thought that melanopsin only existed in the eyes of humans. A study published in Nature showed that subcutaneous white adipocytes express a light sensitive signalling pathway mediated via a melanopsin/TRPC channel axis. It is now evident that melanopsin was present in the skin and fat cells and can translate light signals even if we block blue light from entering our eyes.
When TRPC receptors are exposed to blue light after dark it is very common that inflammation occurs. This is probably one of the reasons why night shift workers are the highest users of prescription pain relief medication and why we have a major dependence on pain medication in the developed world. Personally, if I have my skin exposed to blue light after dark I get very twitchy and itchy and this is sure fire proof that blue light is irritating my skin via the TRPC channels via melanopsin activation.
In humans the bond between melanopsin to retinol is a very weak covalent bond. The bond is easily broken by short wavelength blue light. What do human’s live and work under 24/7? You guessed it, blue light. When you look at rodent models you still find melanopsin in the skin, but how they differ from human’s is they have fur covering the skin, which weakens the influence of blue light on melanopsin. That is why ancestrally speaking when we were covered in hair the main receptors for blue light would be found in the eye. However, we have evolved not to need our body hair and as such have exposed our melanopsin to the outside world. This is now a much larger surface area for melanopsin to be affected by artificial blue and green light after dark.
Study’s in the past have shown that blind people can still have entrained body clocks and can sense brightness of blue light despite not being able to see. They can do this due to heightened perception of blue light via the skin and brain.
In a bid to have a disease free and healthy life we need to protect our mitochondria and repair DNA damage. The way human’s do this is through the production of melatonin. You can increase melatonin production by wearing blue light blocking glasses after dark but if you leave your skin exposed you will not optimise production. You would be leaving valuable melatonin on the table, and given it’s a potent anti-oxidant that repairs DNA damage and stimulates autophagy, why would you want to do that?
Hashimoto's disease which is a disease of the thyroid is increasing throughout the developed world, why is this? It could well be down to the chronic blue light exposure our thyroid has to endure over a 24-hour period. The thyroid is located only as few millimetres below the skin making it very vulnerable to blue light exposure. During the day our necks are exposed to high intensity blue light from digital devices and after dark in our homes and outside. More women than men suffer from Hashimoto's as women typically have their necks exposed to blue light more than men. Men in an office job will typically wear a shirt and/or tie which will add protection to the thyroid and then melanopsin in that area from being damaged by blue light.
If blue light is damaging the thyroid and causing Hashimoto's disease, then it would be plausible to predict that blue light could also be damaging the skin and leading to skin cancer or damaging the nervous system and leading to MS. Many of these types of disease could be a melanopsin dysfunction.
Protecting Melanopsin – a Simple RX
- Wear blue light blocking glasses – get yours here
- Wear a hat when possible during the day and evening. A hooded sweater works well.
- Wear a scarf around the neck during the day and evening when working at your computer
- Cover your skin from top to bottom after dark, wear socks to cover the feet. In hot climates you can use linen clothing which will keep you cool
- Wear gloves to protect the hands.
- When travelling on a plane make sure all the above is followed to help beat jetlag too.
- Make sure your bedroom is light free from inside and outside. Use blackout curtains and a sleep mask to protect the skin from blue light whilst you sleep. Common causes are street lamps and car headlights shining through your window.