Blue light is everywhere. It’s emitted by computers, televisions and smartphones.
It’s also the cause, in some cases, for accelerated blindness and eye disease, according to a new study. Constantly looking at digital devices kills cells in the eye’s retina, and can lead to macular degeneration, an incurable eye disease that usually begins when people are in their 50s or 60s, a recent University of Toledo study found.
Blue light can cause a “poisonous” chemical reaction in the eye’s photoreceptor cells and, when those cells die, they’re gone forever. The good news: There’s a way to prevent the cells from dying.
Ajith Karunarathne, assistant professor in the department of chemistry and biochemistry at the University of Toledo, found one type of molecule — called the antioxidant alpha tocopherol, which is derived from Vitamin E — can stop the poisonous reaction.
As people get older, it’s harder to fight eye disease. Karunarathne said he hopes this research leads to the invention of preventative measures, such as eye drops to protect the retina.
Blue light in the dark can be especially dangerous, previous studies show, and this type of light has been linked to cancer, diabetes, heart disease and obesity, according to a Harvard University study.
The reason is unclear, but researchers have associated exposure to blue light with a decrease in melatonin, the hormone that affects circadian rhythm — the 24-hour human body clock. When the circadian rhythm is off, so are blood sugar levels, which can lead to obesity and diabetes. Screen time is also associated with depression among adults.
sells glasses that block the damaging effects of blue light. They cost between $9 and $60. Refrain from looking at digital devices in the hours before bedtime, and expose yourself to bright lights during the day, which affect the way you sleep at night, as well as your mood and alertness, the Harvard study found.
And if you’re still constantly looking at a screen, remember to blink regularly. Focusing on a screen decreases reflexes and tear production, which causes dry eyes, according to the College of Optometrists.
In the meantime, try the 20-20-20 rule: every 20 minutes, you look 20 feet away for 20 seconds, to give your eyes a break and increase blinking.
Get a daily roundup of the top reads in personal finance delivered to your inbox. Subscribe to MarketWatch's free Personal Finance Daily newsletter. Sign up here.