Better bedtime reading. Adult volunteers who used electronic readers or tablets, such as iPads, for four hours before bedtime had a harder time falling asleep…got less rapid eye movement (REM) sleep…and felt less alert and rested the next morning than when they spent the same amount of time reading a printed book. Why: Tablets emit blue light directly into the reader’s eyes, which can suppress the sleep hormone melatonin and disrupt the circadian clock.
Anne-Marie Chang, PhD, associate neuroscientist, Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Boston.