Researchers have discovered another reason why sleeping in complete darkness is a good idea. The findings suggest that prolonged exposure to artificial lights at night can wreak havoc on our bodies, leading to increased stress, inflammation, and a higher risk of heart disease.
A recent study published at the American Heart Association's Scientific Sessions 2025 has provided strong evidence linking nighttime light pollution to adverse health effects. The researchers found that individuals who lived in areas with high levels of artificial night sky brightness were more likely to experience higher brain stress activity, blood vessel inflammation, and an increased risk of heart disease.
The study analyzed data from 466 adults who underwent a combined PET/CT scan between 2005 and 2008. The researchers also examined the participants' exposure to artificial nighttime brightness at home using the New World Atlas of Artificial Night Sky Brightness. The results showed that those with greater exposure to artificial light had higher stress signals in their brains, blood vessel inflammation, and a significantly increased risk of heart disease.
It's worth noting that even modest increases in nighttime light exposure were linked with higher brain and artery stress, and the correlation remained even after adjusting for known heart risk factors and socio-environmental stresses. The study suggests that prolonged exposure to artificial lights at night can lead to inflammation and increase the risk of hardening of the arteries, which can ultimately contribute to heart attacks and strokes.
So, what can we do about it? Researchers recommend that cities take steps to reduce unnecessary external lighting, while individuals can take simple measures such as turning off screens and reducing indoor nighttime light exposure before bed. By doing so, we may be able to mitigate the negative effects of artificial lights at night on our health.
While the study has its limitations, including a lack of diversity in the participant group and the inability to prove causality due to the observational design, it provides valuable insights into the relationship between nighttime light pollution and heart disease. Further research is needed to expand this work, test interventions that reduce nighttime light exposure, and explore how reducing light exposure might improve heart health.
A recent study published at the American Heart Association's Scientific Sessions 2025 has provided strong evidence linking nighttime light pollution to adverse health effects. The researchers found that individuals who lived in areas with high levels of artificial night sky brightness were more likely to experience higher brain stress activity, blood vessel inflammation, and an increased risk of heart disease.
The study analyzed data from 466 adults who underwent a combined PET/CT scan between 2005 and 2008. The researchers also examined the participants' exposure to artificial nighttime brightness at home using the New World Atlas of Artificial Night Sky Brightness. The results showed that those with greater exposure to artificial light had higher stress signals in their brains, blood vessel inflammation, and a significantly increased risk of heart disease.
It's worth noting that even modest increases in nighttime light exposure were linked with higher brain and artery stress, and the correlation remained even after adjusting for known heart risk factors and socio-environmental stresses. The study suggests that prolonged exposure to artificial lights at night can lead to inflammation and increase the risk of hardening of the arteries, which can ultimately contribute to heart attacks and strokes.
So, what can we do about it? Researchers recommend that cities take steps to reduce unnecessary external lighting, while individuals can take simple measures such as turning off screens and reducing indoor nighttime light exposure before bed. By doing so, we may be able to mitigate the negative effects of artificial lights at night on our health.
While the study has its limitations, including a lack of diversity in the participant group and the inability to prove causality due to the observational design, it provides valuable insights into the relationship between nighttime light pollution and heart disease. Further research is needed to expand this work, test interventions that reduce nighttime light exposure, and explore how reducing light exposure might improve heart health.