Medical investigators from Northwestern Medicine and the University of Illinois at Urbana-Champaign found that office workers with more natural light exposure on the job tend to sleep longer, have better quality slumber, engage in more physical activity, and experience better health and overall quality of life than those exposed primarily to artificial light.
 

Employees with windows in the workplace sleep an average of 46 minutes more per night than those without natural light exposure in the workplace, according to the study, published in the Journal of Clinical Sleep Medicine.
 

"There is increasing evidence that exposure to light, during the day, particularly in the morning, is beneficial to your health via its effects on mood, alertness, and metabolism," said researcher Phyllis Zee, M.D., a Northwestern Medicine neurologist and sleep specialist. "Workers are a group at risk because they are typically indoors often without access to natural or even artificial bright light for the entire day. The study results confirm that light during the natural daylight hours has powerful effects on health."
 

Dr. Zee said architects need to be aware of the importance of natural light not only in terms of their potential energy savings but also in terms of affecting occupants' health. A simple solution: Make sure office workstations are within 20 to 25 feet walls containing the windows.
 

The study group included 49 day-shift office workers; 27 in windowless workplaces and 22 in workplaces with windows.
 

The research was funded, in part, by the National Institutes of Health.