Well this is ironic, you’re exposing yourself to blue light to read this article right?! Admittedly I exposed myself to a fair amount writing it too….
Let’s face it life is becoming increasingly dominated by technology, particularly in the form of screens, and there’s no signs of this slowing down.
But have you ever considered what all this blue light exposure is doing to your sleep, health and waistline??
FIRSTLY A QUICK LOOK AT WHAT ‘BLUE LIGHT’ ACTUALLY IS…
Light is basically made up of electromagnetic particles that travel in waves, the shorter the length of these waves, the higher the energy.
Each wavelength is represented by a different colour and together these wavelengths make up the electromagnetic spectrum (you don’t have to remember any of that!)
The human eye is only sensitive to visible waves, in particular blue waves which are short in length and therefore, you guessed it…..pack a punch in terms of energy.
Blue light is found EVERYWHERE, it’s emitted by the sun and plays an important role in regulating hormones and sleep. It’s also found in abundance in artificial lighting such as fluorescent bulbs, LEDS and incandescent bulbs. Much of today’s electronics use LED backlighting to enhance screen clarity and brightness.
Why do our bodies need blue light?
We use blue light to regulate our body’s biological clock, this is known as our circadian rhythm. These rhythms are dictated by the amount of light we are exposed to and control various bodily processes, such as:
Sleep patterns
Hormone production
Cell regeneration
Eating patterns
Brain activity
When our retinas (layer of cells within the eye) are exposed to natural light this sends a signal to the hypothalamus (key conductor and all round chief of all things in your noggin’) to tell our bodies to produce cortisol, communicating that it’s time to wake up.
At night (when we should be exposed to less blue light) this same signalling process tells the hypothalamus to initiate the production of melatonin which signals to the body that we are ready to sleep.
So if blue light is a part of our natural rhythms, what’s the concern?
Chronic exposure to artificial blue light can confuse these natural rhythms. In today’s society, the retina is receiving signals to boost cortisol at any time of the day and night. This means that our melatonin is suppressed (resulting in shitty sleeping patterns).
It’s no wonder our bodies are crying out for a decent night’s sleep when we regularly go to bed armed with the glare of an electronic device.
These excessive blue waves are changing our brain activity, decreasing delta waves (which induce sleep) and boosting alpha waves (which stimulate alertness). We are literally wired to our technology.
What does this mean for our health?
Disrupted circadian rhythms have huge implications for our health, from hormonal imbalance to immune dysfunction, i’s bad news for health and longevity.
You might feel like you could wing it with a few red bulls and lattes, but this will only cause spikes in cortisol (and blood sugar).
It’s not just technology that affects these natural rhythms, shift workers (particularly those who work night shifts) are more likely to struggle with sleep deprivation and raised cortisol levels due to an over dependence on artificial blue light.
Shift work and this imbalance of circadian rhythms has been linked to increased risk of cancer, heart disease, diabetes, obesity and depression.
How does blue light affect our waistline?
This hormonal imbalance of melatonin and cortisol levels has huge implications for weight gain.
Melatonin causes the hormone leptin to be released during sleep, leptin is our satiation hormone (curbs all the snacky snacks!) and also helps to upregulate your thyroid, which boosts your metabolism! Chronic sleep deprivation due to blue light exposure leads to leptin resistance, hormonal imbalance and consequently weight gain.
Of course it’s a double edged sword! Cortisol also plays a role in several hormonal and metabolic pathways that lead to weight gain. In short:
Increased cortisol = increased insulin & elevated blood glucose levels = fat stored, particularly around the waistline.
Furthermore; chronically elevated cortisol levels increase our appetites and cravings. It also leads to a drop in testosterone levels and consequently muscle mass. The less muscle mass we have, the less calories we burn.
So what can we do about it?
Here’s some simple strategies to reduce blue light exposure:
Screen usually cranked all the way up? Turn down the brightness, particularly after dark.
Use apps that filter blue at night on your phone.
Use the ‘Night Shift’ option within your phone
Avoid using electronic devices 60- 90 mins prior to bed. You could even pick up one of those ancient paperback things.
Get yourself a pair of funky blue light blocking glasses for those evenings when you can't pull yourself away from a netflix binge.
Create a dimly lit environment prior to sleeping - turn down your lights, lamps on low, overhead lights off.
Use red bulbs in the bedroom - red light waves are the most conducive to sleep.
It's by no means rocket science, but even if you can only make a couple of these changes, limiting blue light exposure has huge implications for your sleep, eye sight, waist line and overall longevity of health.
Plenty of reasons not to let blue light dominate your life gang.
Hope this blog helped shed some 'light' on the topic (couldn't help myself).
Coach Harri
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The content in this article is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding your health.