Blue Light Destroying Your Health?

Have you ever been told by a doctor, nutritionist, friend, family member, or just that random dude on the street that your light environment is a fundamental part of your health?

Introduction

Lets be honest, last night you probably went to bed with your phone in hand, staring into that bright blue little box. You may have been watching late night TV, working on your computer, or you just had the lights on in your house. Then you rolled into bed, and if you are like most western individuals, you were probably deprived of a truly restful nights sleep. Upon waking, you immediately grabbed that bright blue screen, checking everything you missed from prior night “sleep”. Next, you went to work, school, or sat at your desk, all while being illuminated from the blue light of your work’s overhead fluorescent bulbs and computer screen. Intuitively, as you’r reading this, you might see how this can be less than ideal for the human body, even without knowing all the mechanisms the body conducts via light stimulation, or lack thereof light stimulation. Therefore, let me guide you through the importance of light, displaying how impactful it really is on our health and wellbeing.

Chronobiology

Every single organism on this planet has built in biological rhythms in response to light, this is what Science refers to as “chronobiology”, or what you may know as circadian rhythm. Since 1878, when Edison patented the light bulb, this vital rhythm has been massively disrupted for the average person. Yet, things really went awry with the advent of modern LED bulbs, which has isolated certain harmful wavelengths of light. Unlike Edison’s incandescent bulb, that has a warm fire like color temp, our modern LED light bulbs are far from a fire akin color. I will say, the problem stems past our light bulbs: it is our phones, computers, TVS, refrigerator lights, car lights and just about any other electrical device we own. Take a look at the below chart.

Examine the second row of the chart: 1850 kelvin, a beautiful orange/red color. This is the color temp of fire, sunset and sunrise. The same, and only, colors our bodies have known after winding down from a long day, or the rising dusk sun after a long dark night. Now, scale up to 5000 kelvin, analogous to your average sun filled sky. This kelvin temperature also happens to be the same for the common light bulb. Take a look at your LCD screen’s color temp: 6,500 - 9500 kelvin (a blue dominant spectrum)! Our body is only accustomed to the blue spectrum at certain points of the day, mainly when UV is at its most dominant (around 10am - 3pm), we were not meant to be consistently exposed to them in their exclusive state as they exist in modern man made light now. This differs drastically from the red spectrum which is ever present in the sun and makes up a majority of the wavelengths, therefore, our body is accustomed to having red as long as the sun is out. For example, just as it wouldn’t be healthy to live solely in a dark cave with the only light being that of a fire, nor is it healthy to live under the constant bombardment of blue light for 12 hours of a day, especially around bedtime. So, let’s dive into the hormonal and biological events that take place as a result of confined blue light stimulation.

Cortisol

As you can see, our light environment gradually gets brighter and bluer on the kelvin scale. We go from a warm red, to an increasingly colder blue as UV and blue light from the sun advances, back to a nice warm red at sunset. Our body has wiring straight from God to handle these natural diurnal changes. As the color temp gets brighter in our day we produce more of something called cortisol, what you may know as the stress hormone. Our bodies uses cortisol as a way to buffer potential inflammation caused by short wave length light such as ultraviolet and blue from the sun, while also keeping us awake and motivated. Without this natural buffer, our skin and organelles would face immense damage. A study aiming to find the affect sunlight had on cortisol found that the “time of sunrise and time of cortisol collection were the most important factors influencing median cortisol. For each hour later that the sun rose there was an almost 5% increase in median cortisol.” The study concluded saying “this is an important finding which is consistent with the understanding that light is the major zeitgeber in entrainment of the human circadian cortisol rhythm”.

Moreover, Cortisol production from UV and blue light, FROM THE SUN, is a natural and good phenomenon that occurs in the body. UV & blue light from the sun generate hermetic stress within the body. Hermetic stress can be very beneficial for the body, this is why saunas and cold thermogenesis are quite beneficial, or even just basic weight lifting. Nonetheless, if one overdoses on either of the two, going beyond the natural threshold, he may get heat stroke or hypothermia. The hermetic response from UV and blue light results in the body producing cortisol: classified as a glucocorticoid hormone, these hormones are responsible for controlling inflammation, metabolism, blood sugar, stress and SLEEP and WAKE cycles. According to the Cleveland clinic, a prominent medical institution, cortisol plays a role in suppressing inflammation: “In short spurts, cortisol can boost your immunity by limiting inflammation. However, if you have consistently high levels of cortisol, your body can get used to having too much cortisol in your blood, which can lead to inflammation and a weakened immune system”. This is why long term use of steroids, such as prednisone, become highly ineffective and detrimental to the body. One of the major class of illnesses plaguing western civilization today are autoimmune diseases.

Autoimmune diseases are theorized to be a result of a malfunctioning immune system. Some of the major prepositions are high levels of stress, high inflammation and poor immune function. While genetics play a role, good genes and bad genes are turned “on” and “off” as a result of our environment. While the underlying mechanisms may be more oblique, one would think a proper environment would result in a healthy and happy immune system. Is a lab rat, whom lives in confined space under non native man made light, going to be better off than his counter part in nature under the full spectrum of light? Whose body is going to be full of glucocorticoids like cortisol? Who will be chronically stressed, inflamed and have an abnormal immune system?

Autoimmune isn’t the only class of illness on the rise, think about what affects a lot of westerners today? Insulin sensitivity and type 2 diabetes (35 million american)! According to a study conducted in 2020, aiming to find cortisol’s affect in population with type 2 diabetes it concluded “the stress hormone cortisol is associated with higher blood sugar levels in individuals with type 2 diabetes (T2D), suggesting cortisol plays a detrimental role in contributing to glycemia in this population.” This makes sense when we examine the relationship between cortisol and insulin. We know that insulin helps shuffle glucose into cells and signals to the liver to store excess glucose. Cortisol has an opposing affect of releasing the stored glucose. Thus, having chronically elevated cortisol can lead to high blood sugar from the flood of glucose.

Reactive Oxygen Species

Much of the damage blue light causes is due to removing it from its natural place in nature: alongside balancing color frequencies like red and infrared. For example, blue light has been shown to cause something called “Reactive Oxygen species” to be produced in the mitochondria. ROS occurs in the mitochondria, specifically within the electron chain transport, responsible for the sythensation of ATP. Normally an atom has a matching electron to balance it out, this means it is stable, however, ROS occurs when an atom’s electrons do not have a counterpart electron. This, when uncontrolled and unbalanced, can wreak havoc on ones cells, due to the highly unstable and reactive properties. ROS induces apoptosis/autophagy within the body, meaning the body is killing off cells. One can infer when this is apart from its normal course of action, it can be quite detrimental to the body, as it damages cell membranes, important lipids and proteins within the cell and even DNA. One such study examined whether blue light, outside of its natural balance from the sun, would produce ROS, it determined that a “robust amount of [ROS] is produced in the ellipsoid when photoreceptors are exposed to blue light… The cumulative effect of light on [ROS] generation over time may implicate a role for mitochondria in light-induced oxidative damage of photoreceptors.” Now, is it any wonder why macular degeneration is on the rise in today’s world.

Closing Shot

Overall, blue light exposure is something we should be thoughtful about, it can cause copious amounts of cortisol within the body, affecting inflammation levels, blood glucose, high levels of stress, potential for insomnia, or just poor sleep. Blue light can also produce inordinate measures of ROS within the mitochondria, destroying DNA, ripping cell membranes apart, damaging cell lipids and proteins and even causing onset apoptosis/autophagy (cell death). Luckily for you, your average house and screen is illuminating you with a color spectrum your body only gets around noon in nature. While this may seem like a long list, it is really only scratching the surface when it comes to light, we haven’t even begun talking about melatonin and blue light’s suppressive affect on the one and only master molecule (hint cortisol and melatonin have opposing goals). I hope this was a high level, yet basic overview of the damaging affects blue light has on the body. If you can do anything to better your health in such a simple and easy order, this would be a quick fix with impressive results. Finally, cut off lights a couple hours before bed, buy a quality pair of blue blockers, change the lighting in your house to incandescent or red at night, get a healthy amount of sun based on your skin tone and stop looking at your danm bright blue phone before you go to sleep and when you wake up!

References

https://pubmed.ncbi.nlm.nih.gov/24156521/ (cortisol study)

https://pubmed.ncbi.nlm.nih.gov/12601064/ (ROS and blue light)

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5551541/ (the affect ROS has on the body)

https://www.sciencedirect.com/science/article/abs/pii/S0109564105000345 (ROS and blue light)

https://my.clevelandclinic.org/health/articles/22187-cortisol (Cleavland clinics overview of cortisol)