(Truth Theory) Though it is quite common for one to respond to last-minute texts or watch a video on their phone before going to bed, the tendency to do so is anything but healthy. This is because the blue light emitted from devices, such as smartphones and laptops, prevents the brain from releasing the hormone melatonin, which is released by the pineal gland and signals the body to go to sleep. In effect, one may have difficulties going to bed and/or feel groggy the morning after.

As Collective Evolution reports, teenagers are most affected by the tendency to stare at screens before bed. This is because the  human body’s circadian rhythm naturally shifts during adolescence. Understanding this, it makes sense as to why experts suggest turning off one’s phone two hours before bed.

The following infographic explains how blue light at night affects your brain and body:

An additional concern from being around technological devices too often is being bombarded by electromagnetic frequencies. In fact, studies have shown that frequent use of cell phones and other devices that emit electromagnetic radiation may contribute to concerns such as cancer.

It’s because of this that Dr. Martin Blank from the Department of Physiology and Cellular Biophysics at Colombia University has joined a group of other scientists urging the United Nations to broadcast the dangers associated with electromagnetic emitting devices.

If you have to look at your phone before you go to bed or use a laptop within 2 hours of bedtime, install an app called f.lux, which adjust the color of your computer’s display to the time of day (warm at night and brighter during the day). Additionally, make note of when you’ve been on the computer for more than two hours at a time and spend your evenings doing something productive — away from technology, such as putting together a puzzle or going for a walk with a loved one.