The Effects of Night-Time Light Exposure on Your Sleep

The Effects of Night-Time Light Exposure on Your Sleep

Light is essentially a messenger that tells your brain what time of day it is. 

It is the ‘master time-giver’ for your circadian clock, and it determines when you fall asleep. 

When the sun disappears each evening, this environmental cue signals your brain to produce melatonin, your key sleep hormone. 

Melatonin rises steadily in the evening and reaches it’s peak in the middle of the night when you are in your deepest sleep, then, levels decrease until morning light cancels out melatonin production until the following evening. 

More melatonin means you fall asleep faster, sleep for longer and get deeper, more restorative, higher-quality sleep. 

Not only is melatonin crucial for your sleep, but it also effects the function of virtually all other hormones in your body including those related to manging weight, mood, digestion and every aspect of your mental, physical and even sexual performance. 

We cannot emphasis enough HOW important it is that you do all that you can to protect your brain’s ability to naturally produce melatonin at night.

The problem is the type of modern lights that we exposure ourselves to at night-time and the impact that they have on melatonin production.

For millions of years, the only light that our ancestors would have been exposed to after sunset was firelight. Firelight contains yellow, orange and red wavelengths of light which we could consider to be night-time light frequencies.

These days, we exposure ourselves to high amounts of bright artificial light at night that contains blue and green wavelengths. Blue and green are day-time light frequencies given off by the sun and for millions of years they disappeared from view after sunset. 

Science has now shown that exposure to blue and green light after sunset signals to your body that it’s still daytime. 

In studies where participants were exposed LED light from an iPad for 2 hours before bed, this was shown to block melatonin production by up to 50%, delay its release by 3 hours that evening and by 90% minutes the following evening – the ‘digital hangover effect’.

It’s not just iPads that have this effect, it’s any form of bright light in your home (especially LED bulbs) from computers, mobile phones, televisions, tablets and lighting in public areas. 

Put simply, most modern lighting bombards us with exposure to light in the blue and green spectrum which is destroying your sleep and overall health.

It’s also important to understand that it’s not only your eyes that absorb blue and green light. 

Studies have shown that shining blue light on the back of your knees and eye lids also leads to decreased melatonin!

Your body’s external organs are light sensitive – therefore you must block all blue and green light from contacting your skin and eyes at night in order to sleep well.

Next, I’ll expand on this post with practical knowledge and simple action steps that you need to optimise your night-time light exposure for better sleep..! 

😴 💤🌛

In health,


Founder of The Sleep Superstore

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