Our body's activity levels fall and rise to the beat of our internal drums - the 24-hour cycles that govern fundamental physiological functions, from sleeping and feeding patterns to the energy available to our cells. Whereas the master clock in the brain is set by light, the pacemakers in peripheral organs are set by food availability. The underlying molecular mechanism was unknown.
Now, researchers at the Salk Institute for Biological Studies shed light on the long missing connection: A metabolic master switch, which, when thrown, allows nutrients to directly alter the rhythm of peripheral clocks.
Since the body's circadian rhythm and its metabolism are closely intertwined, the risk for metabolic disease shoots up, when they are out of sync. "Shift workers face a 100 percent increase in the risk for obesity and its consequences, such as high blood pressure, insulin resistance and an increased risk of heart attacks," says Howard Hughes Medical Investigator Ronald M. Evans, PhD, a professor in the Salk Institute's Gene Expression Laboratory.