Phones, tablets and computer screens emit blue light that can disrupt sleep. But do you know why? University of Virginia Dr. Scott Schecter, an expert in sleep disorders, says it’s because the light ...

Most adults wish they could catch more ZZZs for better health, sharper focus or simply to wake up feeling rested. Despite that desire, sufficient sleep remains elusive for millions. About one in three ...

The following story is excerpted from TIME’s special edition, The Science of Sleep, which is available at Amazon. Anyone who has nodded off on the subway, faked alertness in a meeting at work or ...