XINHUA – Exposure to bright lights at night and darker days is associated with an increased risk of death, an Australian research has found, reported Xinhua.
The research, published yesterday by Flinders University in South Australia, analysed over 13 million hours of data collected from light sensors worn by 89,000 people.
It found that those who were exposed to high levels of light at night had a 21 to 34 per cent increased risk of death while those exposed to high levels of daylight had a 17 to 34 per cent reduction in their risk of death.
The authors said light exposure at night disrupts the body’s circadian rhythm, the cycle of physical, mental and behavioural changes over 24 hours, by weakening the signal of the central pacemaker that orchestrates the rhythm.
“Exposure to brighter nights and darker days can disrupt our circadian rhythms, a disruption that is known to lead to various health issues, including diabetes, obesity, cardiovascular disease, mental health issues and increase the risk of death,” senior author and sleep expert from Flinders University Sean Cain said in a media release.
“These new insights into the potential adverse impact of light have shown us just how important personal light exposure patterns are for your health,” Cain said.
Lead author Daniel Windred said the findings demonstrated the importance of maintaining a dark environment across the late night and seeking bright light during daylight to enhance circadian rhythms.
The study was based on data from 89,000 United Kingdom Biobank participants, aged 40 to 69, who wore light sensors on their dominant wrist for seven days under free-living conditions between 2013 and 2016. Participant mortality was captured by the National Health Service across a follow-up period of eight years.
