Overdosing Blue Light
"The dose makes the poison" is a fundamental principle in toxicology, attributed to the Swiss physician and chemist Paracelsus from nearly 500 years ago. This concept emphasizes that the toxicity of a substance depends on its dose or concentration, rather than its inherent properties alone.
Two good examples of this are blue light and seed oils. Yes, the color blue coming out of your phone, tablet, HDTV, monitors, headlights, streetlights and work/home LED bulbs and vegetable oils used in everything from organic tortilla chips to restaurant french fries. There are so many parallels between the massive overuse of these two metabolic disruptors I had to write about it.
TLDR:
We’re hardwired to respond chemically to different frequencies of light
Circadian rhythm, cortisol, and melatonin are chemical switches in part controlled by the color blue
In the early 2000s a serious mismatch began in our light environment
Both girls and boys experienced precocious puberty due to massive increases in screen-based blue light during COVID lockdowns
Early puberty is associated with shortened lifespan and a host of metabolic disorders like diabetes, obesity and CVD
Blocking blue in the evening and getting full spectrum sunlight during the day reset and align you to nature’s hardwiring of these light-chemical cues
When I was thirty five I had serious sleep problems and was getting about 4-5 interrupted hours of sleep per night. The first effective thing I learned to help fix it was to see light as food. Frequencies of light in the visible and near visible spectrum act like catalysts for enzymatic and chemical reactions.
An increasingly well-known example is light’s role in circadian rhythm and more specifically melatonin and cortisol. Blue-enriched light, especially around 480nm, has a necessary biological role that we evolutionary evolved with.
At dawn, the light frequencies of the sun are infrared, red, orange and yellow. From sunrise until about 1 hour after sunrise there’s a large increase in blue. Once the sun-earth angle reaches 10 degrees, UV-A light reaches the surface. UV-B radiation becomes more significant when the sun's angle is approximately 30 degrees or higher above the horizon. The same frequency of procession occurs in reverse at the end of the day until darkness.
Our early ancestors created light from wood, oil or candle fire which matched the frequency spectrum from sunset and dusk, a marked absence of blue. Incandescent bulbs came into widespread use in the 1890s, fluorescents in the 1950s and LEDs in the early 2000s.
Incandescents (A) match the sunset/dusk light spectra like fire does however with the onset of fluorescents we see a shift away from our biological matching. Fluorescents (B,C) have a large spike in the green spectrum which has a similar, yet far less potent effect on cortisol and melatonin as blue. LEDs (D,E) have a huge spike in blue which caused our circadian rhythm to really come off the rails.
Biologically we’re hard-wired to increase cortisol and decrease melatonin with blue exposure. One study found that blue-enriched white light (6,500 K) decreased melatonin levels by 53.18%, compared to a 20.17% decrease with warm white light (3,500 K). The natural transition through these color spectra in morning induces an immediate and greater than 50% elevation of cortisol levels. This cortisol spike helps to wake the body and increase alertness.
In my case of sleep recovery, blocking all blue light at night and waking at sunrise to stand outside looking in the direction of the sun reset my circadian clock so profoundly that after day 3 of this practice I no longer needed an alarm to wake at sunrise. And, as long as I block the blue at night waking at sunrise persists to this day.
Blue light, like PUFA, is necessary but we are being overwhelmed by the dose.
Our current frequency diet of blue light and food diet of PUFA share many commonalities.
In addition to LED bulbs, phones, tablets, and laptop screens typically have a blue-enriched color profile by default. Blue requires less energy to produce the same or greater perception of brightness. This helps to extend battery life and lower energy bills.
Just like we need polyunsaturated fats, the amount we need vs the amount consumed is dramatically different. With seed oils, most Americans are getting 25x more PUFA than our ancestors in the 1890s. Today, soybean oil (PUFA) represents about 25% of total calories for the average American equaling 38 pounds/year.
Its estimated that Americans today are getting 21x more blue light exposure than in the 1950s, most of that increase occurring since 2000. Today, Americans spend on average 7 hours on blue-enriched devices and 14 waking hours inside (home, work, school) with blue-enriched bulbs and screens.
These blue and PUFA excesses are also outcompeting other pro-metabolic frequencies and fats creating serious deficiencies in our light and food diets.
With both PUFA and blue light, the dose makes the poison and we’re being massively overdosed.
The reason seed oils are so cheap is due to billions of dollars in federal farm subsidies for soy and corn.
In April of 2022, the Department of Energy effectively banned the manufacture and sale of incandescent bulbs. This rule requires light bulbs to emit a minimum of 45 lumens per watt. Incandescent bulbs generally only produce about 15 lumens per watt. The ban went into full effect on August 1, 2023.
These interventions create a similar outcome in both cases - more seed oils and LEDs in the market.
Prepubescent children exhibit higher levels of melatonin than any other age group. It is theorized that the high melatonin production in children is what suppresses puberty. For those of you that have or had young kids, you can see this by their extended sleep schedule.
If melatonin is inhibited by blue light in those years it triggers early puberty. Girls entered puberty 2 years earlier during covid lockdowns because of the massive increase in screen time.
Another devastating physiological response caused by excessive blue light is that it increases estradiol. This combined with melatonin suppression is the current theory for the effect on girls during lockdown. This is serious. And for boys, the changes in melatonin and increased estradiol causes lowered testosterone due to inhibiting testicular growth and disrupted sleep (when testosterone is made). Its worth mentioning that even though these effects are overtly visible in children, they’re happening to all of us.
Both blue and PUFA elevate estradiol and excess estradiol is demonstrated to increase cortisol!
Early puberty can have significant long-term health implications. In a study published by Nature, early puberty in boys is linked to shortened lifespan. Children who experience early puberty are more likely to be obese. Early menarche in girls is associated with a higher prevalence of type 2 diabetes and other metabolic syndromes.
As covered here and here, cortisol and estradiol are the primary inhibitors of thyroid hormone conversion in the liver. With reduced active T3, the body adapts by slowing down metabolic rate in turn producing less energy.
Other Conditions Associated with Excess Blue-light Exposure
Increased risk of breast, prostate, and colorectal cancers (especially in night shift workers)
Attention focusing problems (in children)
Accelerated aging of brain cells (fruit flies)
Neuro-degeneration (in animal studies)
Reduced libido (due to sex hormone disruptions)
Another nefarious feature of LEDs is called flicker. Though flicker exists in incandescents, there is a buffer in how quickly the light turns off essentially making it meaningless. The amount of flicker is much higher in LEDs. LEDs use an on/off binary switch that occurs 120 times/seconds equally the speed of your incoming power energy grid, 60 hz in the USA. The detrimental effects of flicker are eye strain, headaches, neurological problems, elevated heart beat, among others. Combining flicker and blue is the worst possible light pairing.
Fortunately, flicker-free LED bulbs are available now so if you’re forced to use them they are far better options than flicker LEDs.
This is a special mention for the coolest damn health tech I’ve seen in awhile - Daylight. Its a blue light-free, flicker-free tablet that reads like an old school newspaper, writes like a pen and paper, and runs on android. I’ve seen so many anecdotal reports on X from people raving about how much its helped their circadian rhythm, sleep, attention and mood.
The ultimate circadian flex? Late morning coffee, working on your Daylight while sunning with your feet in the grass…
Excessive blue and PUFA are illusively and directly destroying metabolic health, shortening lifespan and reducing fertility but in different ways. Minimizing them will have a dramatically positive impact on your health.
Minimizing Artificial Blue Light Stack
Change your home bulbs to incandescent. I like this store and the vintage Edison-style bulbs.
LEDs have improved over that last few years. If buy them search for “flicker-free” and “amber” LED bulbs like this.
Put strong filters on your devices. I like f.lux since you can manually reduce blue more than Apple’s Night Shift.
Or, just go straight for the Daylight for yourself and kids. Awesome for everything except watching film.
E-Ink monitors are devoid of blue light and flicker unless they use frontlight LEDs. I don’t have any recs, but if you do please forward to me.
If you travel or are driving at night, use blue-blocking glasses like these. There are many different frames out now.
Get more sun. Red, Infrared and UV balance the overabundance of artificial blue. Red increases mitochondria output of ATP. Near-infrared light triggers the production of subcellular melatonin within mitochondria. UV-A improves circadian rhythm and energy production (via absorption at complex 1). UV-B increases vitamin d synthesis.
When you wake in the morning, go outside for a walk few minutes letting incident sunlight into your eyes
For the elite circadian maxxer there is Krypton. A 4 ft tall light panel with NIR, Red, UVA and UVB. I’m asking Santa for this one. Perfect for this low sun winter season!
To your health,
Jonathan
This is for informational purposes only and should not replace professional medical advice. Consult with your physician or other health care professional if you have any concerns or questions about your health.
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