#9 12/02/14

BODY CLOCK

     Scientists used to believe that our 24-hour cycle sleeping and walking was governed entirely by external factors. The most notable of these, they thought, were the rising and setting of the sun. But the have now established that there is a daily rhythm to a wide range of biological function - including temperature, digestion and metal activity - which are regulated internally by a special time-keeping mechanism within the brain.

     The main function of this "body clock" is to anticipate and prepare for external changes so that, for example, our body temperature starts to rise around dawn, gearing up for the day, and begin to fall in the early evening, winding us down for sleep.

     Some people's body clocks keep poorer time than others, which can greatly disturb their lives and even threaten their health. Insomnia, depression, fatigue, poor work performance and even accidents can  all be caused or aggravated by inaccurate body clocks.

     Equally, severe problems can result from the difficulties of adjusting to different time zones and working by night instead of by day. Shift workers are known to run a higher-than-average risk of having a number of health problems and the disruption or normal body rhythms is one possible explanation for this.