Pediatric "Department"

　　These eye care products cannot prevent myopia. If the hope of protecting eyesight is placed on them, it will make students and parents relax their vigilance, ignore eye health, and increase the risk of myopia.

　　Wei Ruihua

　　Director of Tianjin Primary and Secondary School Students Vision Health Management Center, Chief Physician of Tianjin Medical University Eye Hospital

　　The winter vacation is approaching, and parents are beginning to worry that their children's excessive use of electronic products will cause myopia.

Therefore, they searched for various eye protection products from the Internet - eye protection tablets, anti-blue light glasses, projectors, eye masks, eye patches, lutein... With the mentality of "more than nothing", they let children use them, in order to protect their precious vision.

　　So, are these products "artifacts" or "placebos" for eye protection?

Wei Ruihua, director of Tianjin Primary and Secondary School Students Vision Health Management Center and chief physician of Tianjin Medical University Eye Hospital, said in an interview with a reporter from Science and Technology Daily that these eye protection products cannot prevent myopia. If the hope of protecting eyesight is pinned on them, Instead, it will make students and parents relax their vigilance, ignore eye health, and increase the risk of myopia.

　　Blue light is not the culprit of myopia

　　Many parents think that the blue light emitted by electronic products is the main culprit that causes myopia.

Therefore, they did everything possible to find "artifacts" for anti-blue light, no blue light, and blue light reduction.

　　For example, the eye protection tablet that has been sold on the Internet recently.

Relevant manufacturers say that they use blue light wave peak red shift technology, which can effectively reduce the amount of blue light radiation from electronic screens.

At the same time, compared with ordinary tablets, the display of the eye protection tablet is clearer, and the brightness can be adjusted according to the light, reducing the irritation to children's eyes.

　　Another example is blue light blocking glasses.

Relevant merchants claim that the glasses lenses are affixed with special films, including amethyst film, gold film, blue film, green film, yellow-green film, etc. Children can effectively block blue light after wearing anti-blue light glasses and then using electronic products. Protect retina and vision.

　　There are also projectors that are popular among parents. Businesses claim that they can not only effectively block short-wave high-energy blue light, but also block the direct light generated by the screen, thereby greatly reducing the damage of light to children's eyesight.

　　So, can blocking blue light prevent myopia?

　　"Blue light refers to visible light with a wavelength of 400 to 500 nanometers. Most of it comes from sunlight, and common light sources such as LED lights we use every day also have blue light. Blue light is also divided into beneficial and harmful. The 445-nanometer wavelength band can penetrate the cornea and lens to reach the retina directly, and long-term exposure may indeed damage retinal cells." Wei Ruihua introduced, but my country's recommended standard for photobiological safety is that the radiance is less than or equal to 100 units , within this range, there will be no blue light hazard, and the radiance of most electronic products in life is within 1 unit.

　　In the first half of 2019, the China Consumers Association purchased 13 representative electronic products on the market for testing, and the relevant indicators of all products were within the safe range.

　　"At present, there is no evidence that blue light can cause myopia in children. For children, we advocate the intake of full-spectrum light." Wei Ruihua said that if you choose unqualified anti-blue light glasses, such as darker colors and brighter light Lenses with a high blocking rate will not only not protect the eyes, but will aggravate visual fatigue, and may even increase the degree of myopia.

　　Wei Ruihua pointed out that in fact, the blue light emitted by electronic products is not the real culprit in causing myopia. The long-term, uninterrupted, close-up, and improper use of electronic products leads to overuse and eye fatigue, which is the culprit of myopia.

　　Wei Ruihua reminded that when children look at electronic products, they should follow the principle of "better big than small, rather far than near".

At the same time, parents should control the time their children use electronic products.

For example, children in preschool or lower grades of primary school should not spend more than 1 hour a day accumulatively using electronic products.

For teenagers, the cumulative use of electronic products should not exceed 2 hours per day.

In addition, it is best to take a 20-second break when looking at objects 20 feet (6 meters) away after using your eyes for 20 minutes.

　　Eye mask, massager, and lutein cannot prevent myopia

　　"The principle of some steam eye masks and hot eye patches on the market is mainly to speed up blood circulation in the eyes through appropriate temperature, thereby relieving visual fatigue. In addition, steam also has a certain relieving effect on dry eyes." Wei Ruihua However, this kind of eye mask and eye patch has no effect on preventing myopia, and children with sensitive skin should use it with caution.

　　Businesses claim that eye care massager can relieve visual fatigue by pressing acupoints, but there is no scientific basis to prove that it has control and treatment effects on myopia.

"Everyone's eyes are different, and the positions of the acupoints around the eyes are also different. If the eye care massager can't find the acupuncture points, the massage will be ineffective. If it is pressed on the child's eyeball and the vibration intensity is too strong, it will It will cause damage to the eyes.” Wei Ruihua suggested, “It is more convenient and safer to use an eye massager than children to do eye exercises by themselves. We advocate primary and secondary school students to do eye exercises for 5 minutes each in the morning and afternoon. In addition, appropriate ball games Exercise is also good for myopia prevention and control."

　　Studies have shown that specific nutrients such as lutein, carotene, vitamin A, zinc, etc., have certain preventive and health care effects on dry eye, certain retinal diseases, and macular degeneration.

However, these nutrients have not been found to play a role in the prevention and control of myopia.

　　"Many foods are rich in lutein. As long as children have a balanced diet and eat well, they can get enough lutein." Wei Ruihua said that if children are severely picky eaters, they can supplement lutein appropriately under the guidance of doctors.

　　Related Links

　　Experts teach you to choose eye protection lamps scientifically

　　Click on the online shopping app and search for "eye protection lamp", and the products that appear will definitely make parents dazzled.

The price of eye protection lamps on the market ranges from tens of yuan to several thousand yuan, "A-level", "AA-level", "glare-free and low-shadow technology", "diffuse reflection lighting principle", "three-dimensional double light transmission"... words are dazzling.

　　"When choosing eye protection lamps for children, one of the most important principles is that the relevant parameters must meet the national standards." Wei Ruihua, director of Tianjin Primary and Secondary School Students' Vision Health Management Center and chief physician of Tianjin Medical University Eye Hospital, introduced that the national standard GB implemented in 2018 /T9473-2017 "performance requirements for reading and writing desk lamps" has clear requirements for the color rendering, color temperature, blue light hazard, stroboscopic, illumination, uniform illumination and other indicators of reading and writing desk lamps.

　　For example, "National A-level" and "National AA-level" are divided according to indicators such as illuminance and illuminance uniformity in the national standard.

Among them, the illuminance "National A-level" means that the illuminance in the 120-degree fan-shaped area less than or equal to 300 square millimeters should be greater than or equal to 300 lux (Lux); the illuminance in the 120-degree fan-shaped area greater than 300 square millimeters and less than or equal to 500 square millimeters should be Greater than or equal to 150 lux.

"National AA level" means that the illumination is greater than or equal to 500 lux and greater than or equal to 250 lux under the same conditions.

　　"Illuminance has a certain impact on children's vision. If the illumination is insufficient, the light will be darker, and the child will not be able to see things clearly, so they need to look closer, which will affect the vision." Wei Ruihua introduced that uneven illumination will cause children to suffer. When looking at things, in order to adapt to the changes in light and shade, the pupils are constantly adjusted, which is easy to cause visual fatigue.

　　At the same time, when choosing an eye protection lamp, pay attention to the color temperature, and try to choose an eye protection lamp with a color temperature of about 4000 Kelvin (K).

"If the color temperature is too low, the light will be warmer and more yellow, and the human eye will not be easily fatigued but easy to hypnotize; if the color temperature is too high, the light will be colder and bluer, which is easy to cause visual fatigue." Wei Ruihua said.

　　In addition, try to choose eye protection lamps without stroboscopic.

Wei Ruihua explained that with every flickering, the pupils of the child will shrink and expand, which will increase the burden on the eyes and make the eyes feel tired.

　　"The essence of any eye protection lamp is to improve children's lighting environment. Therefore, we recommend that children not only turn on the desk lamp when they read and write, but also place the desk lamp on the opposite side of the writing hand to prevent shading and shadows." Wei Ruihua said, The ceiling light should be turned on at the same time as the table lamp, because the lighting range of most table lamps is still limited.

Dome lights can provide background light, and the overall visual light environment is also very important for the protection of eyesight, so it is generally recommended to use dual lighting.

　　Of course, no eye protection lamp can reach the illuminance of outdoor sunlight.

The study found that when the ambient illuminance exceeds 1000 lux, a good myopia prevention and control effect can be achieved.

Illumination of 1000 lux is difficult to achieve indoors, but it is easy to achieve outdoors even on cloudy or overcast days (sunny days can reach 8000 to 10,000 lux at noon).

　　"If possible, try to ensure that children's accumulated outdoor exercise time reaches 2 hours a day. If you cannot go outdoors due to epidemic prevention and control, you can also take the next step and choose to bask in the sun on the balcony or window sill." Wei Ruihua said, as long as lighting Well, activities on the balcony can also play a role in preventing and controlling myopia.