As anticipation builds for the longer days that follow this weekend's switch to daylight savings time, the moment seemed ...

As sunlight filters through your window each morning, a quiet, powerful rhythm pulses inside your body. This inner clock tells you when to sleep, eat, and wake. It keeps pace with the 24-hour cycle of ...

If you want to know your chronological age, simply count the candles on your next birthday cake. Calculating your biological age, though, is a little more complicated. Chronological age is the number ...