Shorter wavelength blue light that is emitted by smartphones, lights, and computer, tablet, and TV screens causes damaging health effects. Exposure to this wavelength of light disrupts circadian rhythms. Exposure to blue light after the sun goes down interferes with sleep. Blue light may contribute to heart disease, obesity, diabetes, and other health conditions. Minimize your exposure to unnecessary light, including smartphone screens, after dark. You will also sleep better if you get a lot of exposure to natural light during the day.
Do not text while driving and avoid talking with your cell while driving. Get a head set.