Does More Outdoor Light at Night Help Cause Macular Degeneration?

As the levels of artificial outdoor light during nighttime increase, so do the chances of developing age-related macular degeneration (AMD), a leading cause of vision loss.

Can Outdoor Light at Night Contribute to Macular Degeneration?

By Ernie Mundell HealthDay Reporter

News Picture: Does More Outdoor Light at Night Help Cause Macular Degeneration?

As levels of nighttime artificial outdoor light rise, so do the odds for a leading cause of vision loss, age-related macular degeneration (AMD).

South Korean researchers found that people living in areas of that country with the highest levels of streetlights and other artificial light had more than double the odds for AMD, compared to those living in areas with the lowest levels.

That risk remained even after they accounted for confounding factors such as sleep issues and depression, said a team led by Dr. Ahnul Ha, of the department of ophthalmology at Jeju National University College of Medicine.

City dwellers may be at particular danger for macular degeneration, since the link between the illness and artificial outdoor light “was found solely in urban areas, where the mean outdoor-artificial-light-at-night level was 3 times higher than in rural areas,” Ha’s group reported.

They published their findings Jan. 16 in JAMA Network Open.

Shedding Light on Macular Degeneration

AMD occurs when a part of the eye’s retina called the macula deteriorates over time. People begin to lose their central vision, making common tasks such as driving or reading difficult.

AMD “generally affects people over the age of 60,” said Dr. Matthew Gorski, an ophthalmologist at Northwell Health in New Hyde Park, N.Y. “Common symptoms of macular degeneration include blurry vision, distortion [where] straight lines appear wavy. The symptoms can be anywhere from minimal to severe, blinding vision disturbance.”

In the study, Ha and her team wondered if the proliferation of artificial light at night could play a role in the disease, since it’s already been linked to conditions such as obesity, heart disease, certain cancers and mental health disorders.

There’s also research suggesting that artificial light might harm the retina in various ways. Light exposure can damage sensitive retinal cells, Ha’s group noted. It can also upset circadian rhythms and damage these cells, and it can trigger hormonal changes that might also be harmful.

In the new research, Ha and her colleagues analyzed data on over 126,000 South Koreans ages 50 or older. About 4,100 of them had been diagnosed with AMD.

Her group also tracked where these people lived, comparing that to satellite imagery showing light levels across South Korea at night.

People’s residences were divided into four quartiles, ranked by how much artificial outdoor light they might be exposed to at night.

The main finding: Older people who lived in urban areas with the highest levels of outdoor artificial light had 2.17 times the odds of developing AMD, compared to folks living in areas with the lowest levels.

Living in an area that had even just a bit more nighttime artificial light (compared to areas with the lowest levels) was still linked to a 12% higher risk for AMD.

That suggests that as levels of artificial light rise, so do the odds for the eye disease.

Of course, a brightly lit nighttime environment might raise the odds for sleeplessness or even depression, the team noted. But the findings were unchanged even after adjusting for those factors, they said.

The risk rose with age, and men seemed to be more affected than women, the study found.

Other factors – obesity, smoking and drinking – also seemed to strengthen the link between outdoor light at night and AMD.

For his part, Gorski stressed that the study “does not show any causality. It doesn’t show or prove that outdoor light causes macular degeneration. It is the first study that does show that there may be a link.”

“At this point, I am certainly not going to tell my patients to change their behaviors or to wear glasses in outdoor light at nighttime,” said Gorski, who is also an assistant professor of ophthalmology at Hofstra University’s Zucker School of Medicine in New York.

“I think this is just a first datapoint and additional studies are going to be needed to confirm whether these results are in fact true,” he added.

His advice to people concerned about aging eyes: “I think the best treatment is prevention. So, I always tell patients smoking cessation, eating a well-balanced diet, [including] fruits and vegetables and foods that are high in antioxidants, and wearing sunglasses when you can is a good way of preventing or decreasing the risk of macular degeneration.”


Pink Eye (Conjunctivitis) Symptoms, Causes, Treatments See Slideshow

More information

Find out more about AMD at Johns Hopkins Medicine.

Reference List: 1. Age-Related Macular Degeneration on 2. The Impact of Sleep Quality in the 30s and 40s on Memory Later in Life on 3. Depression and Military Service on 4. Obesity and its Link to Various Health Conditions on 5. Heart Disease Risk and its Relation to High Cholesterol and Hypertension After 55 on 6. New Blood Test Able to Detect 18 Cancers in Early Stages on 7. The Connection Between Bigger Families and Poorer Mental Health in Kids on 8. Organ Aging and the Differentiation in Risks on 9. How Smoking Causes the Brain to Shrink on 10. The Benefits of Weight Loss and Fasting on Gut Microbiome in People on 11. The Latest on Pill Available for Postpartum Depression on

Debunking the Dark Side of Night Lights

People often say that the brightest light casts the darkest shadow. Well, it turns out that the same can be said for artificial outdoor lights at night and its possible link to age-related macular degeneration (AMD).

In a recent study conducted by researchers at Jeju National University College of Medicine in South Korea, it was found that areas with higher levels of streetlights and other forms of artificial light had a significantly higher prevalence of AMD compared to areas with lower levels. 🌃🔦

The study showed that the risk of developing AMD was more than double for those living in areas with the highest levels of artificial light. Even after accounting for factors such as sleep issues and depression, the connection between AMD and outdoor light remained strong. The risk was especially pronounced in urban areas, where the mean outdoor artificial light levels were three times higher than in rural areas. 🌆

AMD is a degenerative eye disease that affects the macula, a part of the retina essential for central vision. As the disease progresses, individuals may experience blurred vision, distorted lines, and even complete loss of central vision. It primarily affects older individuals, typically those over the age of 60. 🕒👴

While the study does not establish causality between artificial light and AMD, it raises important questions about the potential risks associated with excessive nighttime illumination. It is well-known that artificial light can disrupt circadian rhythms, damage retinal cells, and even trigger hormonal changes. These factors could contribute to the development and progression of AMD. 🌌

Interestingly, the study also found that other lifestyle factors such as obesity, smoking, and drinking may exacerbate the link between outdoor light at night and AMD. This suggests that maintaining a healthy lifestyle overall, including a well-balanced diet and regular exercise, could help decrease the risk of developing the disease. 🍔💨🍺

Ophthalmologists, however, caution that more research is needed to validate these findings before any definitive conclusions can be drawn. The study serves as an important starting point for future investigations into the relationship between artificial light and AMD. In the meantime, it is advisable to focus on preventative measures such as smoking cessation, antioxidant-rich diets, and wearing sunglasses to protect the eyes from harmful UV rays. 😎

So, the next time you step outside and bask in the glow of the city lights, remember to take care of your eyes too. After all, you don’t want to trade a bright world for a blurry one. 💡👀


Q: Can artificial outdoor light at night cause macular degeneration?

A: While a recent study suggests a possible link between artificial outdoor light at night and macular degeneration, more research is needed to establish a definitive cause-and-effect relationship.

Q: Who is most at risk for age-related macular degeneration?

A: AMD primarily affects individuals over the age of 60. However, certain lifestyle factors, such as obesity, smoking, and excessive alcohol consumption, may increase the risk.

Q: What are the common symptoms of macular degeneration?

A: Symptoms of macular degeneration may include blurry vision, distorted lines, and difficulty with central vision tasks such as reading and driving. It is important to consult with an ophthalmologist for a proper diagnosis if you experience any of these symptoms.

Q: How can I lower my risk of developing macular degeneration?

A: While the relationship between outdoor light and AMD requires further investigation, maintaining a healthy lifestyle by quitting smoking, eating a balanced diet rich in antioxidants, and wearing sunglasses can help decrease the risk of macular degeneration.

Q: Should I be concerned about the artificial light in my neighborhood?

A: It’s always a good idea to be mindful of your environment. While the study suggests a potential link between artificial outdoor light and AMD, the research is still in its early stages. However, taking proactive steps to protect your eyes, such as wearing sunglasses, is always beneficial.

More Information

Find out more about AMD at Johns Hopkins Medicine.

SOURCE: JAMA Network Open, Jan. 16, 2024; Matthew Gorski, MD, ophthalmologist, Northwell Health, New Hyde Park, N.Y.

Related Article

Common Eye Problems and Infections

Common Eye Problems and Infections

Eye diseases can cause damage and blindness if not treated soon enough. Learn the warning signs and symptoms of common eye conditions such as glaucoma, cataracts, pink eye, macular degeneration and more.

Read more: Common Eye Problems and Infections

📣 Share Your Thoughts!

Do you find this information about the potential link between artificial light at night and macular degeneration concerning? Share your thoughts and experiences in the comments below! And don’t forget to share this article with your friends and family to spread awareness. Together, we can take better care of our eyes! 👀💙