There are 365 days in a year, but some may be one of a kind, and in D.C., Friday seemed one of those unique days, and not just because it was the first full day of spring. The equinox, which in theory ...

As daylight diminishes people can feel their mood dimming. Experts say starting light therapy in the fall can help fend off winter depression. As the days get shorter, many people may also find their ...

As clocks spring forward, light and movement are cues for daytime wakefulness that can improve sleep and overall health ...