Children are more sensitive to blue lightso any potential impact could hit them harder, but another clue that blue light may not be the problem is the difference Impact of interactive screen versus passive screen use.. Relaxing in front of the TV, or even reading on your phone, is more relaxing than playing a video game or messaging in a group chat, although blue light exposure is the same.
Another problem with the way we use screens is that we tend to stare and blink less frequently, which can cause our eyes to dry out. Whether you call it computer vision syndrome or digital eye strain, most of us have experienced itchy or red eyes, blurred vision, headaches, or neck or back pain at some point, usually after working on a computer. Experts still recommend the “20-20-20” rule: Every 20 minutes, try to look at an object at least 20 feet away for at least 20 seconds.
Can glasses or blue light filters help?
An entire industry has emerged from concerns about blue light exposure. You can purchase special glasses, filters, and bulbs that block blue light, not to mention software options, including dark modes. But do any of them really help, or is this just scaremongering designed to sell misleading technology?
In theory, they may work, Peirson says, but the evidence is not straightforward. He highlighted this review, suggesting a positive influence on sleep latency in people with sleep disorders, jet lag, and variable shift work. But he says the problem with most studies is that participants’ actual light exposure is not measured, and the wavelength these filters block is often poorly described.
The blue light has a shorter wavelength (between 400 and 495 nanometers) than red light (620 to 750 nanometers). But different filters block different wavelengths, making it tricky to compare them. Peirson says cutting out longer wavelengths may be more effective at reducing light exposure on our circadian rhythm (our natural sleep/wake cycle), but it can also affect visual function, making it difficult to see.
This Cochrane Library Review examined several studies and found “no clinically significant difference” between regular lenses and blue light filter lenses. He American Academy of Ophthalmology and the college of optometrists In the UK they say there is no evidence that blue light from screens is damaging our eyes, and they also do not recommend blue light blocking glasses.
This study of blue light filter applications suggests that they don’t improve sleep either and that dark mode may not be as good for your eyes as you think. So what are we supposed to do?
Turn off the lights
If you’re worried about getting a good night’s sleep, establishing a bedtime routine is key. The intervention with the greatest evidence base is cognitive behavioral therapy for insomnia (CBT-I), according to sleep expert Sophie Bostock. She was part of the team that worked on Sleepio, which cured my insomnia. It is a six-week course that combines several simple techniques:
- Wake up at the same time every day.
- Use a sleep diary to monitor your sleep patterns.
- Don’t go to bed unless you’re sleepy.
- Get out of bed when you’re not sleepy.
- Use cognitive techniques to address a racing mind, such as mindfulness, journaling, and cognitive reframing.
Bostock also says that if you get a lot of natural light during the day, your body clock will be less sensitive to the effects of light at night. A morning walk or coffee in the garden before starting work can help kick-start your circadian clock.
While blue light has the potential to harm us, it can also be good for us. One study They exposed students to artificial blue light or warm white light for an hour each morning and found that blue light not only reduced melatonin levels; several students also reported increased alertness, positive mood, and visual comfort.
As with most things in life, balance is key. Ultimately, you should avoid bright light before bed, but the blue light emitted by the dimmed screen of a smartphone or TV isn’t worth worrying about.
That said, taking a break from screens at night is probably a good idea, especially for kids. Podcasts and audiobooks are a great way to relax without screens. And if you must use your smartphone in bed, follow this painfully simple rule: stick to fun things and avoid anything stressful.