Researchers found that this type of light therapy led to greater daytime activity, earlier bedtimes, regular sleep patterns and improved sleep quality, offering a promising, non-pharmacological approach to address age-related sleep challenges. 
As people age, their sleep patterns often change, leading to difficulties falling asleep, waking up earlier, more frequent nighttime awakenings, and overall poorer sleep quality. These changes are linked to age-related changes in the eyes and reduced exposure to daylight, often due to decreased mobility and social interactions, alongside increased exposure to artificial light at night, particularly if they live in care homes. 
The study, published in GeroScience, investigated the effects of different light conditions on 36 adults aged 60 and over. Participants self-administered both a control white light and a blue-enriched white light for two hours in the morning and two hours in the evening, over an 11-week period. Researchers carefully monitored sleep patterns and activity levels using wearable technology and sleep diaries. 
The study found that the timing of light is crucial. They found that blue-enriched light is only beneficial in the morning, while exposure in the evening makes it more difficult to fall asleep and causes more restless nights. 
This content is taken from University of Surrey

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