Kyla Dawn

Kyla Dawn

April 1, 2025

Alzheimer’s: Newly Identified Risk Factor Worst in These US States, According to Map

Excessive light pollution could be a new Alzheimer’s risk factor, raising the likelihood of cognitive decline, particularly in younger populations. New research highlights the importance of reducing light exposure at night. Disrupting sleep with artificial light may negatively impact brain health over time. Understanding how nighttime lighting affects us is key to minimizing these risks. This emerging link between light pollution and Alzheimer’s is a critical area of research for future prevention.

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According to a 2024 study published in the journal Frontiers in Neuroscience, high light pollution correlates with higher Alzheimer’s rates in the U.S. The new Alzheimer’s risk factor of light exposure was found to be stronger than other common risks like alcohol or depression. This suggests that artificial light at night may play a significant role in Alzheimer’s development. People living in areas with higher light pollution may be more vulnerable. The growing body of research points to light pollution as an important environmental factor.

High-Risk States: Urban Areas and Light Pollution

Image Credit: Voigt et al. | Frontiers in Neuroscience

States with large cities, like California, New York, and Illinois, have high levels of light pollution. Due to city lights and streetlights, these areas are experiencing a higher new Alzheimer’s risk factor. People in these regions often have disrupted sleep patterns, which can affect their brain health. This makes urban environments a major risk factor. Urbanization and increased artificial lighting at night increase the chances of Alzheimer’ s-related problems.

Low-Risk States: Rural Areas with Less Light

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In rural states like Wyoming, Montana, and Vermont, light pollution levels are much lower. These areas naturally offer protection against the new Alzheimer’s risk factor of nighttime light exposure. With fewer buildings and streetlights, the circadian rhythms of people in these states are better regulated. Less artificial light at night means better sleep and, potentially, a lower risk of Alzheimer’s. These regions show that minimizing light exposure can help prevent cognitive issues.

The Role of Circadian Rhythms

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Circadian rhythms play a key role in regulating sleep and wakefulness. Disruption of these rhythms from light pollution can lead to inflammation, stress, and brain degeneration. This makes light pollution a new Alzheimer’s risk factor that can affect cognitive function over time. Maintaining healthy sleep patterns is vital for brain health. Consistent exposure to natural light during the day and minimal light at night helps protect circadian rhythms.

Who is Most Vulnerable to Light Pollution?

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Young people, especially those under 65, are particularly vulnerable to the new Alzheimer’s risk factor of light pollution. Urban living and screen time increase their exposure to artificial light after dark. These lifestyle factors contribute to circadian disruption and potentially heighten Alzheimer’s risk. With younger people still in critical brain development stages, light exposure may have a stronger effect. This emphasizes the need for them to reduce nighttime light exposure.

How Genetics Play a Role

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Genetic factors may also influence how individuals react to light pollution. Certain genes linked to early-onset Alzheimer’s make some people more vulnerable to the new Alzheimer’s risk factor. This genetic predisposition affects how their bodies manage disruptions in circadian rhythms. Understanding this interaction could lead to better prevention strategies. Combining environmental and genetic insights will help identify at-risk individuals.

What the Research Shows

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While the study links light pollution to Alzheimer’s risk, it doesn’t prove causation. The new Alzheimer’s risk factor still requires more research to fully understand its impact. Current findings show a strong association between light exposure at night and Alzheimer’s prevalence. More studies will help clarify whether light pollution directly causes cognitive decline. This area of research holds great promise for future Alzheimer’s prevention strategies.

How to Reduce Light Exposure at Night

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Reducing light exposure at night can help limit the new Alzheimer’s risk factor. Inside your home, use dimmers or opt for warm-tone lightbulbs instead of bright LED lights. Blue light filters on screens and blue light-blocking glasses can also help. These steps promote better sleep and protect circadian rhythms. Small changes in how you manage light can help protect your brain health over time.

Managing Outdoor Light Pollution

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Outdoor light pollution can be reduced by removing unnecessary lights around your home. Using warmer bulbs outside or installing blackout curtains in the bedroom can also help. Eye shades can further block external light, ensuring a better sleep environment. These easy steps can minimize the impact of the new Alzheimer’s risk factor. Limiting light exposure at night is an effective way to protect cognitive health.

The Bottom Line

Map shows which U.S. states have the most light pollution, with is associated with Alzheimer's prevalence.
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The connection between light pollution and Alzheimer’s needs more research, but it’s a growing concern. Reducing nighttime light exposure can lower the new Alzheimer’s risk factor. Whether adjusting lights at home or installing blackout curtains, small changes can make a big difference. These simple steps could protect your brain health for years to come. Make these changes today and safeguard your future.

Read More: Air Pollution Linked to Higher Dementia Risk: Study