Nighttime light exposure linked to increased Alzheimer’s risk

The bright lights that illuminate our cities at night may do more than just help us see. They may also increase our risk of Alzheimer’s disease.

According to a new study published in Frontiers in Neuroscience, there is a link between light pollution at night and the prevalence of this degenerative brain disease.

Disruption of light pollution on circadian rhythms

One hypothesis is that light pollution can have negative health effects by disrupting our natural circadian rhythms, which are our bodies’ critical timekeeping “clocks.” Robin Voigt-Zuwala, lead author of the study and an associate professor at Rush University Medical Center, told The Epoch Times that these rhythms regulate nearly every biological process in the body, including sleep, wakefulness, and biochemistry.

Although the specific mechanisms by which light exposure is linked to Alzheimer’s are not yet clear, Voigt-Zuwara noted that some genetic factors that influence early-onset Alzheimer’s may affect how an individual responds to environmental stressors, such as light at night.

The results suggest that disrupted biological clocks can make individuals more susceptible to disease. “It seems that disrupted biological clocks can also contribute to the development of neurodegenerative diseases,” said Voigt-Zuwara.

Age differences in response to light pollution

The research team combined the light pollution map of the continental United States with existing medical data on known risk factors for Alzheimer’s disease. They studied the effects of different light intensities at night on different populations and found that although the correlation between light pollution and Alzheimer’s disease was shown in people aged 65 and above, the impact of light pollution was more obvious in people under 65.

For young adults, higher levels of nighttime light exposure were associated with an increased risk of Alzheimer’s disease, surpassing other health factors such as alcohol abuse, chronic kidney disease and obesity.

Although the specific reasons for the increased risk are not yet clear, researchers speculate that it may be related to the fact that young people are particularly sensitive to nighttime light pollution.

A call for more education on the risks of nighttime lighting

The findings suggest a need to re-evaluate the role of environmental factors in Alzheimer’s disease and highlight the importance of raising public awareness of the health effects of artificial light at night.

For people living in light-polluted areas, it is recommended to take immediate steps to change their lifestyle, such as using blackout curtains or eye masks to sleep. In addition, the researchers pointed out that reducing indoor blue light exposure through dimmers, filters and warm-colored lights may also help reduce this risk.

The study was based primarily on a U.S. population. The researchers stressed the need for more comprehensive research, which they hope will spur more studies on individual characteristics and the long-term health effects of nighttime light pollution.