No clinical study demonstrated blue light emitted by digital screens was harmful. Encouraging healthy digital device use habits, putting on sunglasses, and going outside and play are more beneficial than getting blue-light-blocking glasses.
Have you ever noticed when you walk into an eyeglasses shop, there are numerous promotions for blue-light-blocking lenses? These advertisements often assert that digital device usage leads to excessive exposure to blue light, which can be detrimental to one's eyes. Naturally, the conclusion they want you to draw or even have served up straight is you should invest in a pair for the sake of eye health.
But is it true? Is blue light bad for the eyes? Do we need blue-light-blocking lenses? Let's dive in and have a closer look!
Medical societies do not recommend wearing blue-light-blocking lenses for digital device use
Respected medical societies, such as the American Academy of Ophthalmology (AAO), the Japanese Ophthalmological Society (JOS), and several others, advise that they do not recommend wearing blue-light-blocking glasses for digital device use. 1,2
Furthermore, in 2021, JOS urged caution over the use of blue-light-blocking glasses. Research has shown blue light affects myopia positively, blocking blue light may have unintended consequences. In other words, these glasses might impact the healthy development of the eye and lead to an increased risk of myopia onset and progression in children.2
JOS also emphasized that while blue light might affect sleep patterns, especially when exposed late at night, there's no concrete evidence that blue light emitted from digital screens is at a level that causes retinal damage. 1,2
In line with this, AAO advises that neither adults nor children need special eyewear, such as blue-light-blocking glasses, for computer use. Instead, they encourage taking regular breaks to avoid digital eyestrain from extended digital device use. 1
Is blue light bad for the eyes?
So, what has research shown regarding blue light? What perpetuated blue light is bad for the eyes? Animal studies from the 1960s showed that exposure to blue light wavelengths (400 and 500), could potentially cause retinal damage due to the high photon energy of blue light. The energy could generate reactive oxygen species and free radicals leading to oxidative damage in the eye.3,4,5
Blue light at high intensity has been shown to damage the retinal pigment epithelium (RPE) and photoreceptors in the retina.5 Some ocular conditions also have been shown to be linked to blue light exposure, such as age-related macular degeneration, sunburn of the eyes (photokeratitis), and cataracts.6
Despite the concerns, it's essential to put things into perspective. Most of the studies that showed evidence of retinal damage due to blue light exposure used radiation levels far higher than what we encounter in our everyday lives. Furthermore, many of the observational studies that showed blue light was linked to macular degeneration estimated blue light levels based on sunlight exposure.
Further, in meta-analysis reviews looking at the effect of blue-light-filtering intraocular lenses (IOLs) or eyeglass lenses on macular health, there were no significant differences in the tested macular degeneration related measures when compared to non‐blue‐light filtering lenses.8,13 This begs the question: are ocular conditions linked to blue light or other sunlight-related confounding factors?
In all, the current understanding implies in real-world settings investing in sunglasses and other appropriate sunlight protection may be more beneficial than blue-light-blocking lenses.
Is blue light bad for sleep?
Our bodies are governed by a natural internal clock that regulates our sleep-wake cycle, influenced by the hormone melatonin. As bedtime approaches, our brain produces melatonin, signaling our body to prepare for sleep. Unfortunately, the prevalent use of digital devices like smartphones and tablets exposes us and our children to blue light, which may interfere with this process.9
Numerous studies have demonstrated that exposure to blue light in the evening disrupts our ability to fall asleep. For example, research indicates that individuals who read from digital devices before bedtime take longer to fall asleep and experience reduced evening sleepiness, melatonin secretion, and morning alertness compared to those who read from printed books.9
This disruption of circadian rhythms might also be a potential risk factor for the progression of myopia. Research in animals has revealed that continuous exposure to light-induced disruptions in circadian rhythms may lead to increased axial elongation and myopia progression.10
But does filtering out blue light help with sleep? Surprisingly, in a small meta-analysis with 136 participants, the use of blue-light-blocking eyeglasses lenses didn't lead to an improvement in sleep quality.13
With all available evidence, AAO recommends refraining from using digital screens two to three hours before bedtime and employing "dark" or "night" mode on devices in the evening. Moreover, AAO also recommends that one does not need to spend money on blue-light-blocking glasses.11
Is blue light good for myopia?
Blue light may be beneficial for children with myopia. Research has revealed that exposure to sunlight, which contains a significant amount of blue light, may reduce the likelihood of myopia onset and progression in children.2
Blue light has demonstrated the potential to help control myopia in numerous studies. For instance, several animal studies showed animals exposed to blue light displayed a tendency toward hyperopia. And in a small exploratory study, it was found that short-term exposure to blue light suppressed myopia and inhibited axial elongation in human eyes.7,12 Supported by promising evidence, there is even a company that is pioneering the development of a blue light-based therapy for treating myopia in children.14
Key takeaways
Navigating the digital age raises concerns about the impact of blue light on our child's eyes. Some alarms surrounding that the blue light is bad for the eyes were based on extreme testing conditions or exposure to sunlight; they do not necessarily reflect real-world exposure levels from digital devices.
Research studies have not provided evidence supporting the notion that blue-light-blocking lenses offer benefits for macular health or sleep quality. JOS even suggested that for children with myopia, blocking blue light might affect the healthy growth of the eye and potentially elevate the risk of myopia onset and progression.
AAO has also stated that at this time they do not recommend any special eyewear for computer use. Instead, they suggest that both adults and children who spend considerable time on digital devices should take regular eye breaks.11
So, let's protect our children's eyesight by encouraging healthy digital device use habits, putting their sunglasses on, and going outside and play to soak up more of that beautiful "blue sky."
SOCIAL MEDIA LINK:
Want to stay connected on the newest happening? Join me
Facebook group: www.facebook.com/groups/myopia/
Pinterest board: https://www.pinterest.com/clearsightcorner/
- American Academy of Ophthalmology. (2021). Should You Be Worried About Blue Light? Retrieved July 20, 2023, from https://www.aao.org/eye-health/tips-prevention/should-you-be-worried-about-blue-light
- Abe, A. (2021, June 8). Experts: Blue light blocking glasses can hurt kids’ eye health. The Asahi Shimbun. https://www.asahi.com/ajw/articles/14358589
- Noell, W K et al. “Retinal damage by light in rats.” Investigative ophthalmology vol. 5,5 (1966): 450-73.
- Ham, W T Jr et al. “Retinal sensitivity to damage from short wavelength light.” Nature vol. 260,5547 (1976): 153-5.
- Pautler, E L et al. “Reversible and irreversible blue light damage to the isolated, mammalian pigment epithelium.” Progress in clinical and biological research vol. 314 (1989): 555-67.
- Cougnard-Gregoire, Audrey et al. “Blue Light Exposure: Ocular Hazards and Prevention-A Narrative Review.” Ophthalmology and therapy vol. 12,2 (2023): 755-788.
- Wong, Nikita A, and Hamed Bahmani. “A review of the current state of research on artificial blue light safety as it applies to digital devices.” Heliyon vol. 8,8 e10282. 15 Aug. 2022.
- Downie, Laura E et al. “Blue-light filtering intraocular lenses (IOLs) for protecting macular health.” The Cochrane database of systematic reviews vol. 5,5 CD011977. 22 May. 2018.
- Chakraborty, Ranjay et al. “Circadian rhythms, refractive development, and myopia.” Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists) vol. 38,3 (2018): 217-245.
- Lee DC, Chakraborty R, Iuvone PM, et al. Eliminating the master clock gene in the murine retina produces myopia. Invest Ophthalmol Vis Sci Supp. 2016;57:3616.
- American Academy of Ophthalmology. (2022). Digital Devices and Your Eyes. Retrieved July 24, 2023, from https://www.aao.org/eye-health/tips-prevention/digital-devices-your-eyes
- Thakur, Swapnil et al. “Short-Term Exposure to Blue Light Shows an Inhibitory Effect on Axial Elongation in Human Eyes Independent of Defocus.” Investigative ophthalmology & visual science vol. 62,15 (2021): 22.
- Lawrenson, John G et al. “The effect of blue-light blocking spectacle lenses on visual performance, macular health and the sleep-wake cycle: a systematic review of the literature.” Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists) vol. 37,6 (2017): 644-654.
- Dopavision GmbH. https://dopavision.com/
Comments