Do blue light blocking glasses for kids work?
Electronic products have become a part of children’s lives. There are a variety of entertainment games, various online courses, and ubiquitous video chats. It seems that we cannot do without electronic products for a moment. Parents are worried that their children’s eyesight will be affected, so they often buy lenses with special functions to prevent myopia. In the market, blue light blocking glasses that claim to be able to effectively block blue light, prevent radiation, and relieve visual fatigue have begun to sell well. Is this really necessary?
What is blue light?
Blue light is an important part of natural light, and it is visible light with a wavelength of 400nm-500nm in the spectrum. Blue light can be divided into short-wave blue light (harmful blue light) and long-wave blue light (beneficial blue light). Short-wave blue light harms people’s vision and causes specific diseases, while long-wave blue light helps people maintain normal physiological functions, regulate biological rhythms, and treat specific diseases.
Blue light can be seen everywhere in daily life. In addition to blue light in the sun, electronic products such as TVs, computers, mobile phones, ipads, and LED lights also produce blue light in our daily.
Does blue light cause damage to the eyes?
Businesses often associate blue light with mobile phones and computers that everyone frequently touches. There are also many terrible explanations about blue light on the Internet, ranging from causing damage to the eyes to causing cancer. Therefore, in recent years, mass media and academic circles have caused heated discussions about the possible impact of blue light on eye health.
It is believed that the reason why blue light harms the eyes is that blue light is not like ultraviolet light which is absorbed by the cornea and lens so that it cannot reach the retina. Blue light can reach the retina through the refractive medium of the eye, and over time it will cause the aging and functional degradation of the retina. But in fact, the eyes have many protection mechanisms in the process of evolution, such as squinting, pupil contraction, lutein contained in the macula of the retina, the anti-oxidant repair mechanism of the retina, etc., which can protect our eyes from the damage of blue light. Also, after scientific testing, the blue light emitted by electronic products is a few percent of the intensity of blue light in natural light, which means that as long as the electronic products are not used continuously every day (for example, more than 8 hours a day), blue light will not be causes obvious damage to the eyes.
Do kids need blue light blocking glasses?
1. American Ophthalmological Association
The American Ophthalmological Association clearly stated that it does not recommend any special glasses. The organization stated that there is no evidence that blue light from electronic devices can cause damage to the eyes. The discomfort that many people experience after watching electronic screens for a long time is due to symptoms such as dry eyes and even blurred vision caused by "digital visual fatigue". The symptoms of using electronic products are related to how we use digital devices, not the blue light emitted from digital devices. There is currently no clinical evidence that blue light causes damage to the eyes, and measures to prevent blue light may be more harmful than blue light itself. It is too early to take preventive measures against blue light and may have unintended consequences.
2. British Association of Optometrists
The association believes that there is a lack of high-quality evidence to support the use of blue shaded glasses to improve people's visual performance, sleep quality, relieve eye fatigue, or protect macular health. There is no research on the effect of anti-blue eyeglass lenses on the health of the macula.
3. Chinese Journal of Ophthalmology
If the blue light is excessive, that is, the human eye is exposed to high-frequency and high-energy blue light, it will damage the rod cells. However, the "rich blue" environment with intensive exposure and the normalized environment are two different concepts. Therefore, it is unscientific to equate "blue light" with "retinal damage". Individualized blue light protection guidance and recommendations should be put forward under different conditions such as different ages, health conditions, and working environments.