We use computers and smartphones for everything from work to socialising to browsing the web, often for over 6 hours a day. However, recent research has shown that this modern phenomenon may be at the root of serious health problems, including cancer, diabetes, heart disease and anxiety.
So, what is blue light exactly? Out of the electromagnetic spectrum (including gamma rays, X-rays and UV rays), the human eye is sensitive to visible light, which can be broken down into 7 different colours or wavelengths. Blue light, one of the 7 colours, is a high energy wavelength emitted from the Sun and computer and phone screens.
It’s been well-documented that exposure to blue light can throw your circadian rhythm out of whack, causing a barrage of problems associated with sleep-deprivation including weight gain. Prolonged exposure to blue light suppresses the secretion of melatonin, the body’s ‘sleep hormone’, signalling the brain to wake up, which, according to a study from the Northwestern University of Chicago, can increase hunger pangs. In addition, inadequate sleep affects levels of hunger-controlling hormones ghrelin and leptin, which can raise blood sugar levels and cravings for high-calorie foods.
Blue light exposure doesn’t just affect your waistline – according to research organisation Blue Light Exposed, our eyes’ natural filters don’t provide enough protection against blue light rays from the sun, let alone the concentrated amounts emitted from computer and phone screens. Too much blue light can lead to eyestrain, headaches and even long-term retinal damage.
Blue light has even been linked to some forms of cancer, perhaps due to the disruption of hormone balance in the body, which can create the ideal environment for cancer cells to grow. It’s also
thought to increase levels of oestrogen, which is involved in the development of
many types of breast cancer.
How can I protect myself?
The best way to reduce your exposure to blue light is to cut down on screen time, particularly after sundown when blue light exposure is most disruptive. Spend your evenings reading, going for a walk or spending time with family and friends.
However, if you can’t avoid using a screen at night, invest in protective opthalamic lenses designed to reflect and reduce blue light, which can help reduce eyestrain. Talk to your optician about which glasses are right for you.
Working in front of a computer all day? Try the 20-20-20 trick: every 20 minutes, spend 20 seconds looking at something 20 feet away to give your eyes a break from blue light glare.
Or install f.lux, a special program that changes the blue light levels according to the time of day, onto your Mac or Windows PC. Download it for free at http://www.justgetflux.com. iPhone and iPad users can now download iOS 9.3, which also has built-in blue light-reducing technology.