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Turn Down the Lights

Turn Down the Lights

How bright light affects our health and environment

Most of us have been there: You’re driving down a country road at night, turn a corner, and are blinded by the headlights of an oncoming car. Blinking the spots away, you follow the white line to your lower right and curse the ubiquity of ultra-bright LED headlights. About a year ago, President Biden began a push alongside Congress to cease production of all lightbulbs that produce lower than 45 lumens — meaning all incandescent bulbs. Former President Trump had previously tried to slow this motion in Congress, saying that banning these bulbs put undue pressure on manufacturers. However, now Biden’s motion has passed; as of August this year, all production of incandescent bulbs will be ended.

The current Administration claims that the order will save Americans $3 billion in energy costs annually. However, the ban is riddled with downsides. In this article, we’ll be focusing on ramifications for both our health and the environment. Light pollution has become an increasingly pertinent issue in recent decades as public service lighting is replaced with brighter and brighter bulbs. I spoke with Dr. Lee Howard, Board Certified General Surgeon and Medical Director at the Human Performance and Longevity Center in Nashville, and famed bro scientist Benjamin Braddock to understand more about how bright light affects our health.


The largest and most easily identified problem with omnipresent bright light is the effect on our circadian rhythm. Dr. Howard points out that in his years of practice he’s found that “lack of proper sleep is a large contributor to aging, disease, and premature death… Universally, people with good sleep hygiene tend to function better.” A study conducted in 2017 stated that long-term sleep disruption can “increase the risk of certain cancers,” among other things, and that even short-term sleep disruption “increased stress responsivity; somatic problems; reduced quality of life (QoL); emotional distress; mood disorders and other mental health problems; cognition, memory, and performance deficits; and behavior problems in otherwise healthy individuals.”

While natural light emitted from the sun helps us calibrate our circadian rhythm, (“In my house the first thing we do in the morning is open the blinds,” states Howard) brighter light on the blue to white spectrum disrupts it greatly — especially when used at night. Even naturally toned yellow light will disrupt sleep patterns when used throughout the night. Multiple studies have found that blue light blocks melatonin secretion, which we need for proper sleep. Dr. Howard says that much of this has to do with the way we are exposed to blue light. Devices like our computers, televisions, and smartphones offer us entertainment often designed to evoke dopamine and emotional response. Instead of relaxing and winding down before sleep, many are overstimulated with a bright light directly facing their eyes.

Any nighttime lighting can be detrimental. Howard mentions one study in which a laser was shone on the feet of sleeping subjects, neurons began to fire away in their brains, interrupting the natural sleep cycle. The implication here is that we have photoreceptors not only in our eyes, but in our skin, and bright lights will disturb our sleep even with our eyes closed. “It’s almost foolish that we wouldn’t believe this is true,” says Howard, pointing out that when early humans rested in caves, the small amount of light that crept in from the morning sun was enough to wake them up.

Howard also mentions the presence of streetlights in both low and high income neighborhoods. At 9 o’clock at night in lower income neighborhoods, many will still be outside of their homes under the blue glow of service lighting. As more of this service lighting is mandated to produce higher and higher lumens in the interest of safety, the sleep of people exposed to it is disrupted more and more. “The very people who need sleep the most are getting less,” notes Howard.


Ben Braddock’s foray into the analysis of blue light started with regular migraines. “I narrowed down the source of my migraine headaches to blue lights,” he explains. “Some of those headaches had stroke-like symptoms. That’s what sent me down the rabbit hole.” He points out that blue light is a very new thing in our history. For millennia our only light sources were fire—in camps, candles, and lanterns. Incandescents, he says, are close to the color spectrum of these natural sources. “Red light actually causes mitochondria to fire up and improve,” says Braddock. “We just don’t work as good under blue light.”

This, he expounds, is because blue light is closer to ultraviolet on the spectrum. As we know, ultraviolet light causes oxidation of cells that leads to a variety of healthy problems including cancer. He cites one study from the Journal of Cosmetic Dermatology which found that exposure to blue light accelerates the aging process and increases instances of problems like cutaneous hyperpigmentation. Of course, a lack of sleep contributes to accelerated aging as well.

Braddock also points out that disconnection from the night sky due to light pollution is sure to have negative effects on our mental health beyond a lack of sleep. “We’re now in a situation where the majority of Americans live in a place where they can’t see the night sky,” he notes. He then mentions that during a large blackout in Los Angeles in 1994, emergency services calls spiked as residents called in a panic to report the sparkle of the Milky Way.

Disruption of sleep on its own will cause a swath of emotional disturbances that come with an influx of stress hormones. Braddock points out that many reported psychiatric disorders may be caused by disturbances in sleep, but admits this could be a “chicken or the egg” situation. “It’s really fascinating how much disruption of circadian rhythm seems to be omnipresent in psychiatric disorders,” he states, citing depression, anxiety, bipolar disorder, and schizophrenia.

Blue light has recently been reported to have negative effects on our metabolism. “There’s emerging research that suggests it induces insular resistance,” he explains, citing a study from the Northwestern University Feinberg School of Medicine. The study compared bright blue light exposure to yellow dim light exposure, and also found that bright blue light exposure caused higher peak glucose levels. Braddock asks why some metabolic rates are so low, mentioning widespread hormonal imbalances and the problem with claiming weight loss is always a matter of willpower as dystopian problems like this uptick.


Braddock points out that light pollution not only hurts us, but the animals that make up our ecosystem. Animals can see varying spectrums of light, but he states that “when it comes to human lighting at night, the worst to disturb the wild is blue and white.” For example, newborn sea turtles will often be confused by artificial light inland, working their way in the opposite direction they need. Moths are a common example of an animal that will be confused so much by our light fixtures that they will destroy themselves. Juvenile salmon are often caught by fishermen shining lights into their waters, but riverside towns will disturb their natural migration passively. Braddock's personal gripe is with the effects of artificial light on lightning bugs, a Tennessee state pride, that will be unable to find their mates in brightly lit areas.

A study conducted in September of 2022 analyzed the effects of the spread of blue-white light replacing orange and yellow light across Europe. It found that blue-white lighting was brighter and had negative effects on the sleep patterns of residents, (predictably) the visibility of stars, and the phototaxic response of insects—where they compulsively move toward or away from artificial light sources. The study also found that the movement and foraging patterns of bats, many of which are a “conservation concern” has been changed severely.


It’s unsettling that this research is only just beginning to come forth, as we are already well into a global switch in our light sources. Braddock comments that these big motions to push cutting edge technology at rapid speed are to blame, and that “by the time we’re aware of the downsides, there’s financial interests” that keep them entrenched. As all manufacturing facilities will be forced to stop investing in incandescent bulbs, this motion is going to be hard to undo even if the next administration wants to. The eerie glow of the empty parking lots miles away from our homes will only get more disruptive.