1. Your family’s electronic devices hide a dark secret: their LED screens disrupt sleep and lead to the development of metabolic disease.
2. Blue light can trigger a rise in blood glucose levels and increase the risk of myopia, depression, obesity, diabetes, and cancer.
3. To protect your kids, you can swap out lightbulbs, adjust screens, and ensure your family wears blue-blocking glasses after dark.
The light of the sun produces a natural curve across the spectrum, shifting in perfect harmony from dawn to dusk and season to season. All of nature has basked under this progression of sunlight since time immemorial, plants and animals tuned to thrive under its daily and seasonal fluctuations. (1)
In the late 1800s, that harmony changed forever with the arrival of the lightbulb. Night turned into day, and our circadian wake/sleep cycles were upended on a global scale. The convenience of electric lights shifted societal behaviors, packing us into schools, offices, shopping malls, and gymnasiums for many hours of the day and night. And in today’s societies, most of those indoor spaces are lit with fluorescents and LEDs. These bulbs emit only visible light, which has a peak in the blue, while missing out non-visible light—infrared and ultraviolet—altogether. (2)
The absence of infrared light in the morning slows the mitochondria, our cells’ energy factories, making them less capable of self-repair, which leaves us prone to cellular damage, inflammation, and ultimately, diseases like myopia, depression, obesity, diabetes, and cancer. (3)
Children are even more sensitive to unbalanced lighting because their bodies are still developing. Have you noticed your kids struggling to wind down after screen time? Blue light could be the cause.
While we may not be able to change the environments where we spend much of our time, there are steps we can take to reduce the risks that unbalanced blue light poses to our health.
With the predominant use of fluorescent and LED lightbulbs in the world today, we are faced with more mitochondrial dysfunction and thus, more metabolic diseases than ever before. Add to that the increased use of devices and screens that emit high levels of blue light into our faces, and we have a recipe for a sick society. (4)
In 2025, an estimated 65% of adults in the US are overweight. Obesity’s health toll is further complicated by diabetes, which affects 14.7% of adults in the US. This is a fourfold increase since 1990, just four years prior to the arrival of the first smartphone in 1994. (5) (6)
High blood glucose, a symptom of diabetes, also damages our eyes. Diabetic retinopathy can develop in anyone with type 1 or type 2 diabetes, causing damage to the blood vessels in the retina. Macular degeneration is also on the rise, affecting approximately 200 million people today, with a projected increase to 300 million people by 2040. (7) (8) (9) (10)
According to a meta-analysis of 145 studies, myopia affects 22.9% of people worldwide, with incidence expected to reach 49.8% by 2050. Research has shown a sharp increase in childhood myopia, linked directly to technology use. Meanwhile, a recent study demonstrated a noticeable decrease in myopia in children who engaged in 40 minutes of outdoor activity during the day. (11) (12)
Globalization has pushed us into a 24-hour society, where nightshifts are the norm, impacting workers in industries like healthcare, manufacturing, and commerce. Not only are the internal clocks of shift workers turned upside down, but these individuals labor inside blue-lit buildings. And when they go home, they are deprived of sunlight while they sleep during the day. This circadian dysregulation has been shown to increase cancer rates, with breast and prostate cancers taking the lead. (13)
With the predominant use of fluorescent and LED lightbulbs in the world today, we are faced with more mitochondrial dysfunction and thus, more metabolic diseases than ever before. Add to that the increased use of devices and screens that emit high levels of blue light into our faces, and we have a recipe for a sick society. (4)
In 2025, an estimated 65% of adults in the US are overweight. Obesity’s health toll is further complicated by diabetes, which affects 14.7% of adults in the US. This is a fourfold increase since 1990, just four years prior to the arrival of the first smartphone in 1994. (5) (6)
High blood glucose, a symptom of diabetes, also damages our eyes. Diabetic retinopathy can develop in anyone with type 1 or type 2 diabetes, causing damage to the blood vessels in the retina. Macular degeneration is also on the rise, affecting approximately 200 million people today, with a projected increase to 300 million people by 2040. (7) (8) (9) (10)
According to a meta-analysis of 145 studies, myopia affects 22.9% of people worldwide, with incidence expected to reach 49.8% by 2050. Research has shown a sharp increase in childhood myopia, linked directly to technology use. Meanwhile, a recent study demonstrated a noticeable decrease in myopia in children who engaged in 40 minutes of outdoor activity during the day. (11) (12)
Globalization has pushed us into a 24-hour society, where nightshifts are the norm, impacting workers in industries like healthcare, manufacturing, and commerce. Not only are the internal clocks of shift workers turned upside down, but these individuals labor inside blue-lit buildings. And when they go home, they are deprived of sunlight while they sleep during the day. This circadian dysregulation has been shown to increase cancer rates, with breast and prostate cancers taking the lead. (13)
Blue light is not our enemy. “Exposure to blue light during the day is important to suppress melatonin secretion, the hormone that is produced by the pineal gland and plays [a] crucial role in circadian rhythm entrainment.” Indeed, if melatonin were our enemy, we wouldn’t have been born with blue-light-sensing photoreceptor proteins called melanopsin in our eyes. (14) (15) (16)
Melanopsin resides in the intrinsic photosensitive retinal ganglion cells (ipRGCs) on the surface of our retina. While ipRGCs only account for 1-2% of all retinal ganglion cells, these melanopsin-containing cells are crucial for maintaining the master circadian clock in our brain. “Short wavelengths, perceived as blue color, are the strongest synchronizing agent for the circadian system that keeps most biological and psychological rhythms internally synchronized.” However, when unbalanced blue light is presented to our eyes at the wrong time of day, it can throw off our master clock, resulting in damaging effects to our health. (17) (18) (19) (20)
Three additional gateways add to this disruption. The first comes via blue light at a specific wavelength of 420 nm. When presented to the ipRGCs, this wavelength has a significant impact on the mitochondria in our eyes. According to a recent study, “One hour [of] environmental exposure to 420 nm induces significant metabolic instability in retinal mitochondria and blood signals…[which] likely restricts respiration and ATP production that may impact…retinal function.” (21) (22)
Image: Source: https://www.sunlightinside.com/light-and-health/natural-light-vs-artificial-light/
The second blue-light issue “identifies 446–477 nm as the most potent wavelength region providing circadian input for regulating melatonin secretion.” When our eyes are exposed to blue light in this range, our melatonin is effectively switched off, leading us to a bad night’s sleep. In addition, this instability in melatonin synthesis raises cancer risk. In an article published in 2022, researchers stated, “the evidence is compelling that melatonin has a variety of anti-cancer effects, such as its inhibition of cancer cell viability, proliferation, progression, and metastasis or even inhibition of cancer initiation.” (23) (24) (25)
The third gateway is blue light’s impact on blood glucose levels. In a study that compared blue-light exposure between day and night, researchers found that “the evening group…had significantly higher glucose peak value during blue-enriched light exposure.” And they concluded that, “Blue-enriched light exposure acutely alters glucose metabolism and sleepiness.” The mechanism for altered glucose levels appears to be a downshift in mitochondrial activity, which slows respiration and heart rate, and reduces energy production, which cripples our cells’ ability to engage in night-time repair activities. (26) (27) (28)
Blue light has invaded many areas of our lives, but that doesn’t mean we can’t adjust our indoor environments in small ways that provide significant gains. One of the least expensive and effective ways to protect your family from blue light after sunset is by wearing blue-blocking glasses. These glasses should block the full-range of blue light (approximately 400 to 500 nm) to ensure adequate protection. (29) (30) (31)
The negative impact of fluorescent and LED lightbulbs during the day can be mitigated by blue-blocking glasses, as well. These glasses are appropriate for wear while shopping at the mall or grocery store. But for multiple hours of daily exposure—say, in the office—adding a small incandescent light or near-infrared enhanced (NIRE) LED to your workspace can go a long way to stimulate the mitochondria in your eyes and improve your vision. And at home, you can swap out standard LEDs for NIRE LEDs or incandescent bulbs. (32) (33) (34)
After nightfall, your children’s bedroom lamps can be turned low and their tablet and phone screens configured to use a warmer color temperature to tone down the blue. Color-shift software—like Iris or f.lux—is also available for additional protection. (35) (36)
Other easy fixes include choosing outdoor activities over indoor ones and driving your car with the windows slightly open to allow sunlight inside. You can do the same at home with a door or window. This is especially helpful if your family utilizes technology inside because it takes very little sunlight to overpower the blue emitted by your screens. (37)
And finally, you can share information about the effects of blue light on our health with your family, friends, employers, school-board members, teachers, fitness professionals, and store owners.
Blue light has invaded many areas of our lives, but that doesn’t mean we can’t adjust our indoor environments in small ways that provide significant gains. One of the least expensive and effective ways to protect your family from blue light after sunset is by wearing blue-blocking glasses. These glasses should block the full-range of blue light (approximately 400 to 500 nm) to ensure adequate protection. (29) (30) (31)
The negative impact of fluorescent and LED lightbulbs during the day can be mitigated by blue-blocking glasses, as well. These glasses are appropriate for wear while shopping at the mall or grocery store. But for multiple hours of daily exposure—say, in the office—adding a small incandescent light or near-infrared enhanced (NIRE) LED to your workspace can go a long way to stimulate the mitochondria in your eyes and improve your vision. And at home, you can swap out standard LEDs for NIRE LEDs or incandescent bulbs. (32) (33) (34)
After nightfall, your children’s bedroom lamps can be turned low and their tablet and phone screens configured to use a warmer color temperature to tone down the blue. Color-shift software—like Iris or f.lux—is also available for additional protection. (35) (36)
Other easy fixes include choosing outdoor activities over indoor ones and driving your car with the windows slightly open to allow sunlight inside. You can do the same at home with a door or window. This is especially helpful if your family utilizes technology inside because it takes very little sunlight to overpower the blue emitted by your screens. (37)
And finally, you can share information about the effects of blue light on our health with your family, friends, employers, school-board members, teachers, fitness professionals, and store owners.
For parents, a single choice—like turning off screens an hour before bedtime—could shift their kids’ restless nights into periods of deep, restorative slumber. The result: brighter, more cheerful children and a happier household all around.
Alex Hayes, CHN, is a Certified Holistic Nutritionist, healer, researcher, and writer. She helps women rewrite their health journeys so they can experience the “happily ever after” they deserve. When not writing, she is studying the latest in nutrition, refining her own wellness practices, or connecting with nature.
