Myopia

Preserving Vision: Ancient Therapies for Conquering Presbyopia, Myopia, and Dry Eyes

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Massage, herbal tea preparations, and ear acupuncture may improve various eye issues, including presbyopia, myopia, dry eyes, and eye strain.

Various eye issues, including presbyopia, myopia, dry eye syndrome, and eye strain, plague people of all ages. In addition to age-related eye conditions, today’s culture of looking at screens throughout the day can acerbate otherwise healthy eyes. Traditional natural therapies such as acupoint massage, drinking herbal teas, exercises for the ciliary muscle (responsible for eye accommodation), and ear acupuncture may yield unexpected benefits.

Traditional Chinese Medicine Eye Care: Nurturing the Liver and Kidneys

According to traditional Chinese medicine (TCM), meridians are the channels through which energy flows in the human body. They are responsible for transporting qi throughout the body. The body consists of 12 major meridians, each corresponding to a specific organ. Their activities follow specific times and pathways (biological clock), aligning with 12 “shi chen” (each representing two hours in modern times) in a day. During each two-hour period, the meridian corresponding to the specific organ experiences increased activity as well as heightened physiological functions in that organ.

In TCM, it is believed that the health of the eyes is closely related to the functions of the liver and kidneys, with a particularly strong connection to the liver and kidney meridians. In other words, nurturing the well-being of the liver and kidneys is the first step toward maintaining healthy eyes.

Establish a Sleep Routine

Staying up too late can harm the gallbladder, liver, and kidneys, leading to kidney deficiency. Most individuals with presbyopia tend to have kidney deficiency, making them prone to eye strain and issues such as dryness, soreness, redness, and tearing. It is recommended to:

• Maintain a regular sleep schedule and avoid staying up late. Aim to be asleep between 11 p.m. and 1 a.m. so that you can enter deep sleep from 1 a.m. to 3 a.m., as these two time periods are when the gallbladder and liver meridians are most active.

• Massage your fingers as they have acupoints associated with the eyes, including the spleen meridian on the thumb, the liver meridian on the index finger, and the kidney meridian on the little finger. Massaging these three fingers can regulate the qi and blood of the eyes, alleviating eye discomfort.

Massage 5 Acupoints Around the Eyes to Improve Presbyopia and Dark Circles

Along the meridians are specific points known as acupoints, which possess unique functions. TCM acupoint massage boasts a rich and extensive history. Directly massaging the five acupoints around the eyes (as shown in the diagram) can help alleviate eye strain and discomfort.

Instructions

Curl your index finger and gently press on these acupoints using the knuckle. Massage them in sequence, repeating the process 20 or 40 times daily to effectively alleviate presbyopia and improve dark circles.

Herbal Teas for Improving Dark Circles

Dark circles are a prevalent concern, often associated with the appearance of fatigue and aging. The underlying cause is typically poor blood circulation around the eyes, described in TCM as “qi stagnation and blood stasis.” It accelerates the aging of the skin around the eyes, leading to sagging eyelids and the formation of dark circles. Factors such as poor sleep, staying up late, excessive eye strain, allergies, and dry eye syndrome can contribute to the development of dark circles.

Drinking tea made from the following five medicinal herbs can help to alleviate dark circles:

• White chrysanthemum—to clear heat, detoxify, improve vision, and remove nebula. It is often used with goji berries to support eye health.

• Goji berries—rich in fiber and lutein, they can nourish the liver and kidneys and help protect the eyes.

• Astragalus membranaceus—tonifies qi and nourishes blood, thereby regulating the circulation of qi and blood.

• Salvia miltiorrhiza—to activate blood, dispel stasis, promote blood circulation, soften blood vessels, and facilitate the generation of new blood, thus preventing the development of cardiovascular diseases.

• Licorice—plays a harmonizing role among the various herbs.

Preparation

Combine herbs and bring to a boil in 35 fluid ounces (3.5 cups) of water and simmer for 15 to 20 minutes, and it is ready to drink. This tea can help to alleviate eye strain and discomfort, as well as slow down the aging of the eyes.

In ancient Chinese texts, the pairing of goji berries and white chrysanthemum in this formula is documented as an excellent eye-protective remedy. These ingredients are often crafted into pills, and taking them regularly is believed to prevent eye diseases. You can also freeze goji berries and grab a few whenever you crave them. They boast a sweet taste, somewhat resembling raisins.

Research has found that Astragalus membranaceus can regulate the immune system, delay aging, relieve fatigue, and alleviate allergies. Additionally, studies have revealed that licorice has hepatoprotective and antimicrobial effects, while chrysanthemum and licorice extracts have been found to exhibit anti-inflammatory and antioxidant activities.

Exercises to Enhance Eye Accommodation Ability

Presbyopia, also known as age-related farsightedness, is a refractive error resulting from the loss of elasticity in the crystalline lens and the surrounding ciliary muscles inside the eyes as we age. This prevents light from accurately focusing onto the retina.

Myopia, or nearsightedness, is also a refractive error that hinders clear vision of distant objects and can lead to eye fatigue or headaches. Myopia can develop in childhood, particularly in modern times when people start using mobile devices at a young age, spend extended periods staring at screens, and engage in prolonged reading—all of which are major contributors to its onset.

In the United States, 128 million people have presbyopia, while 41.6 percent of the population is nearsighted. Among them, approximately 13 million people (4 percent) experience high myopia.

Both presbyopia and myopia stem from a decline in the eye’s accommodation ability and refractive errors. Extended periods of staring at the screens of various devices can lead to infrequent blinking. This diminishes the eye’s accommodation ability and can lead to issues such as myopia, presbyopia, and dry eyes.

We can train the eye’s accommodation ability, specifically the ciliary muscle, through some simple methods. Such training aims to enhance the elasticity of the lens, enabling them to clearly see objects at different distances. The training methods are as follows:

(The Epoch Times)

Alternating Focus Between Distant and Nearby Objects

In an outdoor setting, focus your eyes on a distant object, such as a lightning rod on a building or faraway tree branch, then shift your gaze to a nearby object approximately one foot away. Repeat this process of looking at distance and nearby objects, allowing the eyes to rapidly adjust their focal point. This exercise trains the ciliary muscle to contract and relax quickly, enhancing the eye’s accommodation ability.

Enlarging Small Objects

In an outdoor setting, focus your eyes on a very small object, such as the tip of a tree branch. Then, try to make it appear larger, like the size of a basketball. Next, shift your focus to an even smaller object, such as the top of a wheat spike, and magnify it as well. Repeating this process allows the eyes to concentrate on details, enhancing their sharpness and accuracy.

Adjusting Posture to Prevent Myopia

Sitting posture is also a crucial factor affecting the eyes. Incorrect posture can easily lead to eye strain. When writing or reading, be mindful of the following two points:

• Pen grip—The pen should be held in the correct position—avoid holding it too close to the tip. Some children, when tired of writing, tend to do this, affecting their field of vision and prompting them to unconsciously look downward. This habit can contribute to the development of myopia.

• Reading distance—When reading, it is crucial to maintain a proper distance. Avoid lowering the head, as it can cause the eyes to focus too closely, potentially leading to myopia.

Alleviating Pseudo Myopia With Ear Acupuncture

Ear acupuncture is a TCM treatment that involves inserting needles, attaching small magnet pellets, or placing rice grains on specific acupoints on the ear to stimulate the corresponding areas. This treatment approach aims to regulate qi and blood circulation and treat various health issues. The ear contains numerous acupoints related to the eyes, including the “cervical vertebrae C3 acupoint,” “optic nerve acupoint,” and “eye muscle acupoint” (as shown in the diagram).

(The Epoch Times)
(The Epoch Times)

We can use ear acupuncture to alleviate pseudo-myopia. The following steps can be applied for those with poor eyesight:

  1. Choose the ear on the side with poor eyesight.
  2. Locate the three acupoints mentioned above on that ear.
  3. Attach a small magnet pellet or rice grain to each of these three acupoints and secure them with tape.
  4. Gently cover the eye with poor eyesight and let it rest.
  5. Use your fingers to press on the three acupoints on the ear for about half an hour. Then, open the eye. Vision will gradually improve.

If both eyes are nearsighted, alternate between both ears for this process—this leads to significant improvement.

Study reveals impact of home confinement, distance learning on incident myopia

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Home confinement and distance learning significantly increased the number of hospital visits for myopia at a university hospital in Istanbul, although no correlation was found with myopia progression.

The increasing prevalence of myopia is a major public health issue worldwide. Global estimates suggest a burden of 5 billion people affected by 2050. Home confinement and implementation of long-lasting remote learning techniques due to the pandemic have increased digital screen time while substantially decreasing time spent outdoors.

Empty Classroom
“Our results showed a significant increase in hospital admission rates for myopia during the COVID-19 pandemic compared to admission rates in the period before the pandemic,” Sebnem Egriboyun, MD, said. 

“In Turkey, in-person education was suspended in all schools on the 22nd of March 2020. Additionally, home quarantine became mandatory for all citizens under the age of 20 after April 3,” Sebnem Egriboyun, MD, said at the virtual European Society of Cataract and Refractive Surgeons winter meeting. “These facts led us to the research question: Could the lockdown measures for the COVID-19 pandemic have aggravated the rate of clinical admission or progression of myopia in school-aged children in Turkey?”

The data of patients aged between 7 and 18 years examined between Jan. 1, 2014, and May 1, 2021, were analyzed. Visits were divided into before and during the COVID-19 pandemic, and the percentage of myopia diagnosis in each subgroup was determined. In addition, myopia prescriptions in both eyes were documented, and differences in subsequent visits were used to evaluate progression.

“Our results showed a significant increase in hospital admission rates for myopia during the COVID-19 pandemic compared to admission rates in the period before the pandemic. A similar statistically significant difference could not be determined for the rate of progression,” Egriboyun said.

This study, she said, highlights the importance of preventive measures to avoid the increase of myopia cases due to distance learning methods. These may include limiting digital screen time, advocating for increased outdoor activities and implementing frequent nationwide myopia screening programs for school-aged children.

“We acknowledge that several other factors such as decreased outdoor sunlight exposure during this period might have been relevant, and the respective role of each of these factors should be further investigated,” she said.

Winter brings concern for worsening myopia

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A winter dominated by virtual schooling and indoor activities has the potential to push myopic children further toward high myopia.

For most individuals, the season will not be bad, Michael X. Repka, MD, MBA, told Healio/OSN. “For some at-risk children, though, they may be further pushed into higher myopia, where they could increase their risks to the retina, which develop when they are older,” he said.

There is much speculation about whether another season of quarantine will be worse for preventing the onset and progression of myopia, Repka said.

“If we get a sense from what goes on in East Asia, where kids do study for many hours per day, you worry that maybe this will happen in North America as well,” Repka said.

To reduce the risk for increased myopia progression during the winter, Repka suggested something educators and parents have long known, which is that outdoor time, even in cold weather, is a good thing.

“The data we have are that there is a weak effect of outdoor on slowing progression and a weak effect of preventing onset, so even when it is cold, it is probably worth saying, ‘Recess can happen outside, even in the winter, except on crazy days.’ I think educators and mothers have known that for a long time,” Repka said.

In addition to urging children to get some outdoor time each day, school days that do not demand students look at a computer screen for 6 hours every day should be considered.

To stop myopic progression, there is no single solution, but there are a few trials moving forward, including those for contact lenses and eye drops aimed at addressing the myopia epidemic.

“We’re certainly excited about the ongoing trials of drugs and contact lenses to slow progression, and these will be tools for ophthalmologists to use in the future,” Repka said.

Noninvasive technique to correct vision

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Engineers have developed a noninvasive approach to permanently correct vision that shows great promise in preclinical models. The method uses a femtosecond oscillator for selective and localized alteration of the biochemical and biomechanical properties of corneal tissue. The technique, which changes the tissue’s macroscopic geometry, is non-surgical and has fewer side effects and limitations than those seen in refractive surgeries. The study could lead to treatment for myopia, hyperopia, astigmatism, and irregular astigmatism.
Corneal topography before and after the treatment, paired with virtual vision that simulates effects of induced refractive power change.
 

Nearsightedness, or myopia, is an increasing problem around the world. There are now twice as many people in the US and Europe with this condition as there were 50 years ago. In East Asia, 70 to 90 percent of teenagers and young adults are nearsighted. By some estimates, about 2.5 billion of people across the globe may be affected by myopia by 2020.

Eye glasses and contact lenses are simple solutions; a more permanent one is corneal refractive surgery. But, while vision correction surgery has a relatively high success rate, it is an invasive procedure, subject to post-surgical complications, and in rare cases permanent vision loss. In addition, laser-assisted vision correction surgeries such as laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK) still use ablative technology, which can thin and in some cases weaken the cornea.

Columbia Engineering researcher Sinisa Vukelic has developed a new non-invasive approach to permanently correct vision that shows great promise in preclinical models. His method uses a femtosecond oscillator, an ultrafast laser that delivers pulses of very low energy at high repetition rate, for selective and localized alteration of the biochemical and biomechanical properties of corneal tissue. The technique, which changes the tissue’s macroscopic geometry, is non-surgical and has fewer side effects and limitations than those seen in refractive surgeries. For instance, patients with thin corneas, dry eyes, and other abnormalities cannot undergo refractive surgery. The study, which could lead to treatment for myopia, hyperopia, astigmatism, and irregular astigmatism, was published May 14 in Nature Photonics.

“We think our study is the first to use this laser output regimen for noninvasive change of corneal curvature or treatment of other clinical problems,” says Vukelic, who is a lecturer in discipline in the department of mechanical engineering. His method uses a femtosecond oscillator to alter biochemical and biomechanical properties of collagenous tissue without causing cellular damage and tissue disruption. The technique allows for enough power to induce a low-density plasma within the set focal volume but does not convey enough energy to cause damage to the tissue within the treatment region.

“We’ve seen low-density plasma in multi-photo imaging where it’s been considered an undesired side-effect,” Vukelic says. “We were able to transform this side-effect into a viable treatment for enhancing the mechanical properties of collagenous tissues.”

The critical component to Vukelic’s approach is that the induction of low-density plasma causes ionization of water molecules within the cornea. This ionization creates a reactive oxygen species, (a type of unstable molecule that contains oxygen and that easily reacts with other molecules in a cell), which in turn interacts with the collagen fibrils to form chemical bonds, or crosslinks. The selective introduction of these crosslinks induces changes in the mechanical properties of the treated corneal tissue.

When his technique is applied to corneal tissue, the crosslinking alters the collagen properties in the treated regions, and this ultimately results in changes in the overall macrostructure of the cornea. The treatment ionizes the target molecules within the cornea while avoiding optical breakdown of the corneal tissue. Because the process is photochemical, it does not disrupt tissue and the induced changes remain stable.

“If we carefully tailor these changes, we can adjust the corneal curvature and thus change the refractive power of the eye,” says Vukelic. “This is a fundamental departure from the mainstream ultrafast laser treatment that is currently applied in both research and clinical settings and relies on the optical breakdown of the target materials and subsequent cavitation bubble formation.”

“Refractive surgery has been around for many years, and although it is a mature technology, the field has been searching for a viable, less invasive alternative for a long time,” says Leejee H. Suh, Miranda Wong Tang Associate Professor of Ophthalmology at the Columbia University Medical Center, who was not involved with the study. “Vukelic’s next-generation modality shows great promise. This could be a major advance in treating a much larger global population and address the myopia pandemic.”

Vukelic’s group is currently building a clinical prototype and plans to start clinical trials by the end of the year. He is also looking to develop a way to predict corneal behavior as a function of laser irradiation, how the cornea might deform if a small circle or an ellipse, for example, were treated. If researchers know how the cornea will behave, they will be able to personalize the treatment — they could scan a patient’s cornea and then use Vukelic’s algorithm to make patient-specific changes to improve his/her vision.

“What’s especially exciting is that our technique is not limited to ocular media — it can be used on other collagen-rich tissues,” Vukelic adds. “We’ve also been working with Professor Gerard Ateshian’s lab to treat early osteoarthritis, and the preliminary results are very, very encouraging. We think our non-invasive approach has the potential to open avenues to treat or repair collagenous tissue without causing tissue damage.”

Story Source:

Materials provided by Columbia University School of Engineering and Applied Science.

FDA approves VisuMax Femtosecond Laser to surgically treat nearsightedness

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The U.S. Food and Drug Administration today approved the VisuMax Femtosecond Laser for the small incision lenticule extraction (SMILE) procedure to reduce or eliminate nearsightedness in certain patients 22 years of age or older.

Not all patients are candidates for SMILE, and individuals should carefully review the patient labeling and discuss their expectations with their eye care professional.

“This approval expands the surgical treatment options available to patients for correcting nearsightedness,” said Malvina Eydelman, M.D., director of Ophthalmic and Ear, Nose and Throat Devices, in FDA’s Center for Devices and Radiological Health.

Nearsightedness, or myopia, is a common vision condition in which close objects are seen clearly, but objects farther away are blurred. It occurs when the eye focuses light in front of the retina. This can be due to the shape of the cornea being too steep and/or the length of the eyeball being too long.

The VisuMax Femtosecond Laser removes a small amount of eye tissue to permanently reshape the cornea. A femtosecond (very fast, short-pulsed) laser makes cuts within the cornea, creating a disc-shaped piece of tissue that is removed by the surgeon through a small incision in the surface of the cornea. This tissue removal causes the shape of the cornea to change, which corrects the nearsightedness.

A clinical study of the safety and effectiveness of the device to correct nearsightedness found the procedure resulted in stable vision correction at six months. Of the 328 participants evaluated at six months, all but one had uncorrected (without glasses or contacts) visual acuity of 20/40 or better, and 88 percent had uncorrected visual acuity of 20/20 or better.

Common complications during surgery included difficulty removing the corneal tissue and loss of suction that keeps the laser aligned with your eye. Common complications after surgery included debris at the site of tissue removal, dry eye, moderate to severe glare and moderate to severe halos.

The VisuMax Femtosecond Laser is manufactured by Carl Zeiss Meditec Inc., of Dublin, California.

The Number Of Nearsighted People Keeps Growing

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Myopia, or nearsightedness, is affecting people at record levels across the globe. Around half of the population in America and Europe has the condition, which is double the percentage from 50 years ago. East Asia in particular seems to be suffering from the “myopia boom”: up to 90% of Chinese teenagers are shortsighted, and 96.5% of 19-year-old men in Singapore are, too. Scientists have predicted that half of the world population, or about 5 billion people, will have myopia by 2050. This is a real health concern, because some of those people will have high myopia, a condition that can lead to detached retinas, glaucoma, and blindness.

Sunshine keeps eyes healthy.

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Zurijeta_sun_shutterstock

At least 10 hours a week outdoors in the sunshine is beneficial for young children’s vision, find the researchers.

Exposure to sunshine as a small child is crucial to the development of a healthy eye according to results of long-term myopia study conducted by University of Sydney researchers.

Their findings published this week in the American Academy of Ophthalmology‘s professional journal tables data showing children who spend more time outdoors were less likely to become short-sighted or myopic.

The researchers say that evidence suggests that small children under six years of age should spend at least 10 hours a week outdoors in the sunshine.

Orthoptist Associate Professor Kathryn Rose, from the University’s Faculty of Health Sciences says exposure to sunlight at a young age assists in the growth of a normal healthy eyeball preventing it from growing too fast or over – expanding and becoming oval or egg-shaped instead of round.

The Sydney Adolescent and Eye Study, a five-year longitudinal follow-up study from the Sydney Myopia study, examined more than 2000 children from 55 primary and secondary schools for a number of risk factors linked with myopia.

Professor Rose says all children had a comprehensive eye examination. Accurate measurement of refractive errors (myopia, hyperopia and astigmatism) was conducted using an international standard regime of eye drops, similar to that adopted in WHO studies.

A detailed questionnaire gathered information on the children’s ethnicity, general physical activities including hours spent in outdoor leisure such as cycling, outdoor sports, picnics or walking. Researchers also gathered data on near-sighted activities such as computer use and time taken watching television.

Amanda French, PhD candidate and lead author, says:

“The results show that the protective effect of time spent outdoors as a very small child persists even if a child is doing a lot of near work such as reading and studying.”

While the results of the study showed television watching and computer use appear to have little effect on the development of refractive errors in the eye, children with one or both parents myopic had a greater likelihood of developing the condition but even for those children, time spent outdoors had a mitigating effect. Time spent in outdoor light also reduced the likelihood of myopia developing in children of all ethnicities.

French says prevention of myopia is important for future eye health as even low levels of the condition place you at higher risk of cataracts and glaucoma in adulthood.

“Promoting outdoor activity to parents and families, and including more outdoor pursuits in school curricula could be an important public health measure to avoid the development of myopia,” says French.

 

Source: http://sciencealert.com.au

 

Is reading in the dark bad for your eyesight?

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Claudia Hammond looks at the common warning that straining eyes damages your sight and discovers the evidence is surprisingly blurry.

f you were ever caught reading in low light, or using a torch under the bedcovers to read after lights-out, your parents might well have warned you that straining your eyes would damage your eyesight. Or perhaps you used to hear that it’s easy to spot the studious children at school because they were the ones who had spent so long with their head in a book that they had to wear glasses.

Whatever you heard, the warning that people shouldn’t read regularly in dim light is a familiar one. Carry out a quick internet search, though, and you’ll discover that this is apparently a myth. End of story? Not quite. When you dig a little deeper and look at the scientific evidence, the story becomes much more complex.

Let’s look at the basics first. Short-sightedness or myopia means that a person can easily see things that are close up, but objects in the distance such as the number on a bus or the menu board in a restaurant look blurry. Wearing glasses or contact lenses solves the problem, but it doesn’t answer the question of why some people develop short-sightedness in childhood while others don’t.

Our eyes are cleverly designed to adjust to different light levels. If you are trying to read in the gloom your pupils dilate in order to take in more light through the lens onto your retinas. Cells in your retina, called rods and cones, use this light to provide information to the brain about what you can see. If you are in a dark room, for instance, when you just wake up, this process allows you to become gradually accustomed to what initially feels like pitch-black darkness. If you switch a light on, it feels unbearably bright until your pupils have had time to readjust once more.

The same happens if you strain to read a book in dim light. Your eyes do adjust, but some people find the strain gives them a headache. Likewise when you look at something close-up like a book or some sewing, the eye adjusts, muscles lengthen the area known as the vitreous chamber – the gelatinous bulk of the eyeball that lies between the lens and the retina.

Blurred lines

Unfortunately, there is no convenient set of studies that have examined the long-term effects of reading in the dark. So we have to look at studies that looked at different factors and try to piece together the information.

Most of the research and the debate in short-sightedness has focused on the effects of repeatedly looking at things up close, what researchers call close work, rather than the effects of reading in poor light.

A British study last year, for example, found that close work could influence the onset of short-sightedness in adults but this was not nearly as important as factors such as birth weight or expectant mothers smoking during pregnancy.

Other regions of the world have a higher prevalence of short-sightedness, for instance, as many as 80-90% of school-leavers have myopia in parts of East and South East Asia, leading researchers to wonder whether the long hours children spend studying could cause the problem.

However, any geographical differences in rates of myopia could reflect genetic differences, and there is plenty of evidence that the genes you inherit from your parents are a major factor in short-sightedness. If both your parents are short-sighted there is a 40% chance that you are too. If your parents both have good vision, that risk drops to just a 10% chance.

The classic way to estimate the extent to which genes underlie a condition or illness is to compare identical and non-identical twins. A twin study conducted in the UK demonstrated that 86% of the spread of people’s eyesight scores could be explained by genetic factors. But as the authors of this study point out, this doesn’t mean we should ignore the effect of the environment.

We shouldn’t ignore any complicating factors, though. You could argue that perhaps parents who studied a lot themselves as children and ended up wearing glasses, are likely to encourage their children to do the same, making a genetic association appear stronger than it really is. Or perhaps some children inherit a susceptibility to eye problems, which is then activated by the strain they put on their eyes when they are young.

Donald Mutti and his colleagues in the United States tried to disentangle these complications in a study conducted in California, Texas and Alabama. They found no evidence of a genetic susceptibility and found that the children of parents with poor eyesight spent no more time staring closely at books than other children did. Heredity, the authors insist, was the stronger factor.

Light relief

But returning to possible effects of the environment, there are a set of intriguing studies that have looked at the effect of light – not torchlight under the bedclothes, but bright daylight. Perhaps it’s not the time spent inside squinting at the page that’s the problem, but the lack of time spentoutside. The Sydney Myopia Study followed more than 1,700 six and twelve year olds living in Australia and found that the more time the children spent playing outdoors, the less likely they were to have short-sightedness. A systematic review of studies including those from Australia and the United States found a protective effect overall of spending some time outdoors, particularly in East Asian populations.

Why could daylight help? There used to be an idea that playing sport taught children to focus on distant objects, but in this study it didn’t matter what they were doing while outside as long as they were out in daylight. This appeared to protect some children against the hours they spent reading or studying.

The authors believe that the benefits of being outdoors are less about looking into the distance, and more about the effect that daylight has on your depth of field and the ability to focus clearly. They even suggest that extra exposure to daylight could encourage the production of dopamine, which could then have an effect on eye growth. This hypothesis hasn’t been tested, but if it were to be demonstrated might it explain the low level of myopia in Australia.

With such a variety of papers on this subject with varied findings, what are we to conclude? Genetics undoubtedly has a major impact on rates of myopia, but evidence suggesting that environmental factors may have a role can’t be ignored just yet. After all, no matter how small an effect the environment has, it’s is easier to change than your genes.

The best we can say at the moment is that playing outside seems to be beneficial to the eyes and that perhaps young children should study in a good light to avoid straining their eyes. As for adults, all these studies were conducted on children whose eyes were still developing, so if you still want to read under the covers by torchlight then it’s unlikely to cause you any problems. Of course now that you’re old enough to decide your own bedtime, you probably don’t need to.

Source: BBC