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A well-lit street may be a real treat for your eyes, but not for your brain. According to new research, exposure to excessive light at night can increase the risk of Alzheimer's disease, particularly in younger people.

The study published in Frontiers in Neuroscience looked at satellite acquired light pollution mapsof 48 US states. Using Medicare data, researchers checked prevalence of Alzheimer's disease and different variables which increased risk of the brain disease.

During the study, they created separate night time light intensity data for each state and added them into five separate groups according to intensity.  The data was then compared with different variables which increased risk of Alzheimer's disease.

At the end of the study, the team from Rush University Medical Centerin US found a direct link between the brain disease and excessive exposure to light at night. The connection was stronger in people younger than 65 than older people.

On the other hand, in people aged 65 and older, health conditions like diabetes, high blood pressure, stroke increased risk of developing Alzheimer's disease than exposure to excessive light at night. But light pollution posed a higher Alzheimer's risk compared to some other risk factors like alcohol abuse, depression, obesity and chronic kidney disease.

"Certain genotypes, which influence early-onset AD, impact the response to biological stressors which could account for increased vulnerability to the effects of nighttime light exposure," first author of the study, Dr. Robin Voigt-Zuwala, an associate professor at Rush University Medical Center, said in a statement."Additionally, younger people are more likely to live in urban areas and have lifestyles that may increase exposure to light at night."

Concerned by the findings, researchers recommended to makesome lifestyle changes like using blackout curtains or sleeping with eye masks.

"Awareness of the association should empower people-particularly those with risk factors for AD-to make easy lifestyle changes," Voigt-Zuwala, added later.

Though the study didn't analyze impact of light inside the house, they recommended avoiding blue lights completely or changing it with dimmers and warm light.

Similarly, several studies in the past have linked exposure to artificial light to depression, obesity, cancer, heart disease, diabetes and sleep disorders.

According to experts from European Commission, exposure to light night disrupts the natural circadian rhythm, thus increasing the risk of breast cancer, sleep, gastrointestinal, mood and cardiovascular disorders.

Alzheimer's Disease, which is considered to be the most common cause of dementia, leads to decline in memory, thinking, behavior and social skills.  According to experts at Alzheimer's Disease International, dementia affects someone every 3 seconds. More than 55 million people were affected by dementia in 2020.