Sleeping With Lights On? New Study Warns of Increased Risk of Heart Disease
New Delhi: Sleeping with the lights on at night could be doing more harm than you think. A new international study, involving over 88,000 participants, has found that exposure to brighter night-time light significantly raises the risk of five major cardiovascular diseases, including heart failure and stroke.
The research, led by the Flinders Health and Medical Research Institute in Australia, in collaboration with colleagues from the UK and the US, was posted on the preprint server medRxiv and is yet to be peer-reviewed.
The study highlights that artificial light at night may disrupt the body’s circadian rhythms, a known risk factor for heart-related problems, and this disruption could lead to metabolic and vascular issues.
"Night light exposure was a significant risk factor for developing cardiovascular diseases. In addition to current preventative measures, avoiding light at night may be a useful strategy for reducing risks of cardiovascular diseases," the researchers said in a statement.
The study tracked around 13 million hours of light exposure using wrist-worn light sensors worn by 88,905 participants from the UK Biobank, who were monitored for one week. Researchers then followed their health outcomes and found compelling patterns.
Those exposed to the brightest night environments showed higher risks of coronary artery disease, myocardial infarction (heart attack), heart failure, atrial fibrillation (irregular heartbeat), and stroke compared to individuals who slept in complete darkness.
Importantly, these associations held strong even after adjusting for major risk factors such as physical activity, diet, smoking, alcohol consumption, sleep duration, socioeconomic status, and genetic predispositions.
The researchers also noted gender and age-based vulnerabilities. Women were found to be more affected by night-time light exposure, with stronger associations for heart failure and coronary artery disease, while younger individuals showed increased risks of heart failure and atrial fibrillation.
The team concluded that night-time artificial light, by disrupting circadian rhythms, "may trigger metabolic and vascular perturbations, elevating cardiovascular risk."
This study underscores the growing concern over the health impacts of modern light exposure and suggests that something as simple as sleeping in the dark could significantly support heart health.
Rishika Verma is a graduate from Delhi University. She joined Medical Dialogues in 2023. Her interest lies in reporting health news, hospital updates, health updates, medical case studies, and advancements in healthcare, etc.