Wake up refreshed with a simple evening adjustment

Wake up refreshed with a simple evening adjustment

With no clocks in sight, ancient humans depended on nature to tell them when it was bedtime. At sunset, blue light waves — necessary during the day for alertness, cognitive function, and elevated mood — diminished and core body temperatures dropped to initiate their sleep rhythms.

Sunset and lower core body temperatures are still the primary triggers for sleep. In the evening, our brains are wired to recognise the reduction in blue light and start releasing melatonin, the hormone that tells our brain to start the sleep process. Yet, light-emitting diodes (LEDs) used in electronic devices such as laptops, tablets, and phones negatively impact our sunset trigger by suppressing melatonin. LEDs generate a significant amount of blue light, considerably more than even the light bulbs and tube televisions of yesteryear.

Keeping devices out of the bedroom is one strategy for a good night’s sleep, but we know that may not be possible for everybody. So the next best option is to schedule your devices to filter most of the blue light from sunset to sunrise. A yellow tint on the screens gives you a better chance of falling asleep.

See the screenshots below for more information on the settings on your devices. On a newer iPhone, for example, the path to finding the screen pictured is Settings>Display & Brightness>Night Shift. On an Android device, go to Settings>Display>Blue light filter. On a Macintosh computer, go to the Apple menu>System Preferences>Displays>Night Shift. On a Windows 10 computer, go to Settings>System>Display>Night light. If you have a device from another manufacturer, generally a search in settings will yield a blue-light filter.

Windows 10 Night light


Mac Night Shift


Android Blue Light Filter


iPhone Night Shift


Also, remember other melatonin-suppressing sources around your home. Reduce the use of energy-efficient LED light bulbs as much as possible at night. Turn off your flat screen TV about an hour before bedtime or, at least, adjust the color temperature. For the truly serious, a pair of blue-light filtering glasses may keep melatonin flowing. Those products can be purchased online.

Sleep is important, especially when your work shows no signs of slowing down. Pay attention to your blue-light exposure in the evening and take steps to make a smooth transition into a restful night’s sleep.

Byron K. Patrick is the managing director at Network Alliance, a US-based consultancy specialising in information technology services for accounting firms. To comment on this article or to suggest an idea for another article, contact Neil Amato, an FM magazine senior editor, at