Body's Clock Never Adjusts to Daylight Savings Time

You can't fool Mother Nature, experts say

Health Day: Changing to daylight savings time may give people an hour more of sunlight, but it appears that their internal body clocks never really adjusts to the change, German researchers report.

In fact, daylight savings time can cause a significant seasonal disruption that might have other effects on our bodies, according to the report in the Oct. 24 online edition of Current Biology.

"When you change clocks to daylight savings time, you don't change anything related to sun time," explained lead researcher Till Roenneberg of Ludwig-Maximilians-University in Munich. "This is one of those human arrogances -- that we can do whatever we want as long as we are disciplined. We forget that there is a biological clock that is as old as living organisms, a clock that cannot be fooled. The pure social change of time cannot fool the clock."

People's circadian rhythm -- the body's internal clock -- follows the sun and changes depending on where you live. It actually changes in four-minute intervals, exactly the time it takes for the sun to cross one line of longitude, Roenneberg explained. Read On