Could the bright light from screens and other electronic devices at night slowly damage your eyesight? A new study suggests it might.
Scientists have found that spending time in very bright artificial light during the late evening may increase the risk of several common eye diseases later in life. The research was published in GeroScience.
Humans have evolved under a regular pattern of daylight and darkness. Sunrise tells the body it is time to wake up, while sunset signals that it is time to prepare for sleep. This daily rhythm is controlled by the body’s internal clock, also called the circadian rhythm. The eyes play a major role in setting this clock because they detect light and send signals to the brain.
Modern life has changed this natural pattern. Bright LED lights, large computer monitors, televisions, smartphones, tablets, and powerful workplace lighting allow people to stay active long after the sun goes down.
Although this has many benefits, scientists are increasingly studying whether too much bright light at night may have hidden health effects.
Previous research has linked nighttime light exposure with problems such as obesity, diabetes, heart disease, and poor sleep. However, far less was known about whether it could also affect the eyes themselves.
To investigate this question, researchers analyzed data from 82,826 adults taking part in the UK Biobank. People who already had serious eye diseases were excluded. Participants wore a wrist device that measured both movement and light exposure every 1.2 seconds for one week. Researchers then followed their health for almost eight years.
The study found that people exposed to average evening light levels above 1,000 lux between 8:00 p.m. and 11:30 p.m. had a higher risk of developing age-related macular degeneration, cataracts, and primary open-angle glaucoma.
Their risk of macular degeneration increased by 31%, cataracts by 18%, and glaucoma by 47%. The longer people spent under very bright light, the greater their risk appeared to become.
Importantly, the researchers explained that most household lighting is much dimmer than 1,000 lux. Typical indoor lights produce about 100 to 500 lux. The greatest concern involves unusually bright screens, powerful LED displays, or intense lighting used in some workplaces.
Scientists think bright evening light may disturb the body’s circadian clock. Blue-rich light from LEDs may also increase oxidative stress, damage delicate cells in the retina and lens, and interfere with normal repair processes that usually happen during sleep.
The study cannot prove that bright light directly causes eye disease because it was an observational study. However, the large number of participants and long follow-up make the findings important. Future studies will need to confirm exactly how nighttime light affects eye health.
After reviewing the evidence, the results suggest that reducing unnecessary bright light before bedtime could become a simple way to protect long-term vision.
Dimming screens, using night mode, lowering room lighting, and avoiding very bright light late in the evening are practical steps that may benefit both sleep and eye health. Since these changes are easy to make and carry little risk, they may be worthwhile while scientists continue investigating this promising area.’
If you care about eye health, please read studies about how vitamin B may help fight vision loss, and MIND diet may reduce risk of vision loss disease.
For more information about eye disease, please see recent studies about how to protect your eyes from glaucoma, and results showing this eye surgery may reduce dementia risk.
Source: GeroScience study.
