Are Anti-blue light lenses in schools a tool for protecting eyesight or a waste of money?

Recently, Miss. Wang urgently sought advice in a parent group: "My child's eyes hurt from online classes. Should I get them anti-blue light glasses?" The group immediately erupted with discussion. Some parents showed off their expensive imported anti-blue light glasses, claiming they were very effective; others bluntly said, "It's a complete waste of money"; still others were undecided: "What if they work? It's better to wear them than not."

With the widespread use of electronic devices on campus, anti-blue light lenses have become a new favorite among students. However, ophthalmologists are concerned that these "eye protection devices," which are being heavily promoted by retailers, may actually be harming children's eyes!

Elementary school stage: critical period of development, wear with caution

"Mom, when I wear these glasses, the colors in my drawings look wrong!" complained 7-year-old Xiao Ming. This is not an isolated case, but a common phenomenon among children who wear anti-blue light glasses.

Why is it not recommended for elementary school students to wear anti-blue light glasses?

Elementary school students are in the golden period of visual development. At this stage, artificial interference with the natural light environment may disrupt the balance of refractive development. Experts from the Nanjing Maternal and Child Health Care Hospital point out that anti-blue light lenses have a light transmittance rate that is 3%-5% lower than that of ordinary lenses, which may reduce children's sensitivity to light and impair their color recognition abilities. This is particularly detrimental to elementary school students who are still in the process of visual development.

Not all blue light is “bad.” Blue light with a wavelength of 455-500 nm is beneficial. It can regulate biological rhythms, affect refractive development, and help produce dark vision. Deliberately blocking this beneficial blue light can actually be counterproductive.

The quality of anti-blue light glasses on the market varies greatly. Some poor-quality products have orange-yellow lenses, which cause visual distortion; others block too much blue light, affecting melatonin secretion and interfering with sleep.

Proper posture for elementary school students to protect their eyes:

1. Control screen time: no more than 20 minutes at a time.
2. Prioritize large screens: try to project online classes onto a TV screen.
3. Spend 2 hours outdoors every day: this is currently the most effective method for preventing myopia.

Junior high school: Increased academic pressure, rational choices

Upon entering junior high school, the academic workload increased, and Xiao Hong spent more than five hours a day in front of electronic screens. Her mother spent $800 on anti-blue light glasses, but after a month, her vision had actually deteriorated!

Why should junior high school students be cautious about using anti-blue light glasses?

The American Academy of Ophthalmology clearly states that there is no scientific evidence that blue light from electronic devices damages the eyes. The intensity of blue light from electronic screens is only a few hundredths of that of natural light, and normal use will not cause harm.

The primary cause of myopia among middle school students is not blue light, but rather eye strain resulting from prolonged close-up use of electronic devices. Professor Jin Zibing from the Beijing Eye Institute emphasized: “Controlling the use of electronic devices and engaging in more outdoor activities is far more important than wearing anti-blue light glasses.”
Wearing improperly fitted blue light-blocking glasses can actually exacerbate eye strain. Due to lens color distortion and reduced light transmission, the eyes must exert greater effort to focus, potentially causing headaches, eye strain, and other discomforts.

Recommendations for junior high school students with special circumstances:

- Special needs: If you use electronic devices for more than 6 hours a day, you can choose a qualified blue light protection product (filtering 30%-50% of blue light) under the guidance of a doctor.
- Avoid wearing them all day: Only use them when using electronic devices for long periods of time.
- Have your eyesight checked regularly: At least once per semester by a professional.

High school stage: Self-management period, scientific use

High school senior Li is preparing for the college entrance examination and studies for up to 12 hours a day. On the advice of an ophthalmologist, he chose professional blue light-blocking lenses, but only wears them when using electronic devices during evening self-study.

Principles for using blue light-blocking glasses for high school students:

Quality is key: Choose products with qualified optical parameters. Opt for professional brands like Zeiss and Essilor, and avoid lenses with overly dark tints. Lenses with surface coating technology outperform dyed lenses in optical performance.

Use in specific time slots: Wearing them at night can reduce blue light's interference with the body clock, helping to improve sleep quality. However, avoid wearing them during the day, especially outdoors, to prevent blocking beneficial blue light absorption.

Not a panacea: Even when wearing anti-blue light glasses, it is important to strictly adhere to the “20-20-20” eye care rule: every 20 minutes, look up at an object 20 feet (6 meters) away for at least 20 seconds.

Special reminders for high school students to protect their eyes:

- Beware of marketing traps: Do not believe exaggerated claims such as “smart zoom” and “no increase in prescription.”
- Prioritize addressing eye strain: Use artificial tears to relieve dry eyes and maintain good posture when using your eyes.
- Ensure adequate sleep: Seven to eight hours of sleep per day is key to eye repair.

The Truth About Eye Care That Matters More Than Blue Light Protection

Regardless of the educational stage, the core of scientific eye care does not lie in the lenses:

1. Outdoor activities are key: Two hours of outdoor activities daily, exposing the eyes to full-spectrum natural light, have been proven to be the most effective method for myopia prevention and control.
2. Eye posture determines future vision: Maintain a reading and writing distance of one foot, one fist, and one inch, with the screen slightly below eye level.
3. Diet and sleep are the foundation: limit sugary foods, eat plenty of green vegetables, and ensure adequate sleep.
4. Regular professional eye exams: dilation is mandatory for eye exams under 18 years old to avoid incorrect prescription.
Professor Wei Wenbin, Director of Ophthalmology at Tongren Hospital, put it bluntly: “Instead of spending a fortune on anti-blue light glasses, it's better to take your children outdoors for two hours every day.” Natural light is the best nourishment for the eyes.

Choose wisely

Anti-blue light glasses do offer protective benefits for specific groups (such as those with macular degeneration), but for most students, developing good eye care habits is more effective than any “eye protection gadget.”

The next time you see ads for “online class-specific” or “blocks 95% of blue light” products, remember: businesses are selling anxiety, while children need sunlight. After all, on the path to eye care, the most expensive isn't always the best—what's most suitable is what's scientific.