European scientists have completed a large study showing that bright light lamps can improve sleep in older people who live in cities and rarely spend time outdoors, The Mirror reported. Participants who received more natural light during the day were more active and reported sleeping better, which prompted researchers to test whether artificial bright light could produce a similar effect.
The study found that light therapy lamps did improve sleep, increased daytime activity and helped restore the body's natural circadian rhythm, the internal clock that governs sleep and wake cycles.
The findings, published in the Journal of Pineal Research, also pointed to the role of chronotype. People who are natural "larks", meaning they wake up earlier in the morning and go to bed earlier, generally had better sleep quality than those who prefer to sleep in and stay up late.
Why daylight matters
Dr Daan van der Veen, a senior lecturer in sleep and chronobiology at the University of Surrey, explained that daylight plays a key role in regulating circadian rhythms and sleep patterns. He said older people living in cities often do not get enough quality natural light, and that declining eyesight or mobility problems can make it harder for them to go outside regularly.
Insufficient light exposure can, in turn, lead to sleep and health problems and raise the risk of developing chronic disease. The average adult in the United Kingdom sleeps only 6 to 6.4 hours a night, below the recommended 7 to 9 hours.
Why winter makes sleep harder
Morning darkness and cold become bigger problems as winter approaches. For some people, the shortening of daylight hours can be linked to seasonal affective disorder, known as SAD, a condition that can bring on depression-like symptoms during the darker months of the year.
Researchers have previously linked lack of sleep to cardiovascular problems. Findings presented recently at Europe's largest cardiology conference showed that sleeping longer at weekends may protect against high blood pressure in people who do not regularly get enough sleep. Insufficient sleep prevents blood pressure from naturally dropping at night, which raises the risk of hypertension and a range of other health problems.
How the experiment worked
Getting good quality sleep usually becomes harder with age. To find out how this could be addressed, researchers recruited 200 people aged between 63 and 92 from three European cities: Tartu in Estonia, Bologna in Italy and Amsterdam in the Netherlands.
After two weeks of initial monitoring, participants were split into two groups. One group received a light therapy lamp, while the other acted as a control and received no lamp.
The lamp was placed at head height in the room where each participant spent the most time at home. They were advised to switch it on during the first hour after waking and turn it off four hours before their usual bedtime. Participants followed this routine for at least 12 weeks.
All volunteers wore an actigraphy monitor on their wrist to track their activity levels, along with a light sensor on a pendant to measure how much light they were exposed to. The study was repeated across all seasons to check whether the effect changed depending on the time of year.
A simple, drug-free option
Study co-author Debora Constantino, a PhD student at the University of Surrey, said additional morning light significantly increased activity levels and reduced fragmentation of rest and activity periods among the older participants.
She said this was an important finding because it showed, under real-world conditions, that light could be a simple, non-drug and potentially inexpensive way of supporting healthy ageing.
The researchers said bright light lamps should be considered for use in public institutions, including care homes and other facilities for older people.
