‘Green time over screen time’: how to really look after your eyes | Health & wellbeing

The eyes are “the lamp of the body” according to the Bible; if they are healthy, the body is full of light, and if they are not, there is darkness.

Literally and metaphorically, it’s about money. Our sight is one of the most important ways we interact with the world, and it interacts with us. We take our eyesight for granted, which is why we are so shocked when it begins to disappoint us.

“Blindness is a very frightening disability,” says Professor Lauren Ayton, deputy director of the Center for Eye Research Australia at the University of Melbourne. “But people don’t realize that about 90% of vision loss can be prevented or treated.” And like many other issues, keeping your eyes healthy often comes down to a good diet, staying active and regular checkups.

There are two key periods in life when eye problems become evident. There is an emerging global epidemic of nearsightedness – nearsightedness – in school-age children, with around one in three children and adolescents now nearsighted – and this figure is increasing. And while the exact cause of this increase isn’t clear, research suggests that screen time is a factor — just not in the way you might think.

Screens versus exterior

Despite all the concerns that screen time is the enemy of eyesight, there is actually no evidence that close focus on screens causes myopia.

“The direct evidence that screens are problematic in themselves is quite weak,” says Professor Allison McKendrick, research chair in optometry at the Lions Eye Institute UWA in Perth. What’s more likely is that screen time is taking over time spent on other activities that benefit eye health.

One of those things, particularly in children, is time spent outdoors, says Dr Flora Hui, a clinical researcher also at the Center for Eye Research Australia. “Getting enough sunlight is actually important for their eye growth,” she says. One theory is that sunlight causes the release of the neurotransmitter dopamine, which is important for healthy eye development. Playing outside and away from screens also means the eye focuses on things at a distance, which also contributes to its development.

“I say ‘green time versus screen time,’” Hui says. Encouraging children to go outside for an hour or two a day “has been shown to slow the progression of myopia.”

The “inevitable” decline in your mid-40s

For those who avoid myopia in their youth, the first awareness of the eye’s fallibility comes in midlife, with what ophthalmologists jokingly describe as the “my arms are too short” problem. Anyone in their forties who unexpectedly finds themselves holding a restaurant menu at arm’s length to read it will recognize this syndrome.

It’s called presbyopia, it’s age-related and it’s inevitable. “The need for reading glasses is related to the number of birthdays you’ve had,” says Ayton. This is simply the result of the eye’s transparent, flexible lens, which focuses light on the back of the eye – the retina – and which becomes less flexible as we age. This means it’s less effective at bending to focus light, making it harder for us to see things up close.

Unfortunately, there is no prevention or cure for presbyopia.

The only thing that can be done against presbyopia is to correct this concentration with glasses which, despite some concerns, do not make the eye weak or lazy. Ayton says people often complain that as soon as they wear glasses their vision gets worse and worse, but that’s the natural progression of eye aging.

“Wearing glasses is not going to make your eyes weak,” she said. “Almost every two years your reading prescription will be updated.”

Cataract is another common age-related eye condition, and it also affects the lens of the eye. “As the lens gets bigger, it gets fuzzier, so now instead of looking through a nice clear lens, you start looking through a blurry lens,” says Hui. Like presbyopia, cataracts are not preventable, but they can be treated by completely replacing the lens with a new artificial lens.

Early diagnosis

The two age-related eye problems that can be prevented, or at least slowed, are glaucoma, caused by progressive damage to the optic nerve, and age-related macular degeneration, which affects the central part of the retina at the back of the eye.

Although a healthy diet and not smoking can reduce the risk, the most important prevention is early diagnosis. “The message that needs to be given to people in their 40s and 50s is that it’s really important that you get regular eye exams,” says McKendrick. “Major age-related eye diseases, such as glaucoma, macular degeneration, etc., initially show no symptoms, and so this may slowly disappear over years.” By the time they become symptomatic enough to prompt people to see a specialist, they’ve already lost much of their vision, and it’s not coming back.

The key to healthy eyesight and vision lies in the “three O’s,” says Ayton: staying away from screens, being outside, and seeing an optometrist or ophthalmologist regularly.

“For general check-ups, people should see the optometrist – if they are under 60 – every two to three years, and then over 60 it becomes more regular as the risk of eye diseases increases.”