Could Artificial Outdoor Light at Night Increase Alzheimer’s Risk?
In recent years, various studies have highlighted the impact of different factors such as diet, stress, lack of sleep, obesity, and gut inflammation on increasing the risk of Alzheimer’s disease in certain individuals. However, a new study suggests that artificial outdoor light at night could also play a role, particularly for individuals under the age of 65.
Researchers from Rush University Medical Center in Illinois conducted a study comparing light pollution maps across 48 US states to medical records in those areas. The results revealed a statistically significant link between light pollution and Alzheimer’s disease prevalence.
According to medical scientist Robin Voigt-Zuwala, “We show that in the US there is a positive association between Alzheimer’s disease prevalence and exposure to light at night, particularly in those under the age of 65. Nightly light pollution may be a crucial risk factor for Alzheimer’s disease.”
The study found that for individuals over the age of 65, light pollution ranked ahead of risk factors such as alcohol abuse, chronic kidney disease, and depression but behind other factors like diabetes and high blood pressure. However, for those under 65, light pollution emerged as the primary risk factor for Alzheimer’s disease.
While the exact mechanism behind this link is not fully understood, disruptions to sleep and circadian rhythms caused by artificial light are known to have a significant impact on overall health. Voigt-Zuwala suggests that certain genotypes influencing early-onset Alzheimer’s disease may play a role in increasing vulnerability to the effects of nighttime light exposure, especially for younger individuals who are more likely to live in urban areas with increased light pollution.
It is essential to recognize the potential impact of modern-day lifestyles on health, including the widespread exposure to artificial light at night. With more than 80 percent of the global population affected by light pollution, simple lifestyle changes such as using blackout curtains or sleeping with eye masks can help mitigate the risks associated with nighttime light exposure.
The findings of this study, published in Frontiers in Neuroscience, underscore the importance of understanding the implications of artificial light on health and the need for individuals, especially those at risk for Alzheimer’s disease, to make informed choices regarding their exposure to nighttime light.
