sleepBloggers on the National Institute for Occupational Science and Health Science (NIOSH) blog are the latest to weigh in on the hot topic of sleep and work.

In a post entitled...Sleep and Work, Claire Caruso, PhD, RN, and Roger R. Rosa, PhD discuss NIOSH's efforts to research sleep's relationship to work safety.

A growing number of American workers are sleep deprived. In the 1980s, 24% of  American workers surveyed reported getting six or fewer hours of sleep per night -- considered insufficient by sleep experts. In the 2000s, that figure is 30%.

Caruso and Rosa say that work demands are one reason behind the change.

"The timing of a shift can strain a worker’s ability to get enough sleep. Working at night or during irregular hours goes against the human body’s biology, which is hard-wired to sleep during the night and be awake and active during the day."

Nonetheless, many workers in a variety of fields, including public safety, healthcare, utilities, food services and manufacturing are required to work outside of daylight hours.

The resulting shift work, say Caruso and Rosa, is linked to poorer sleep, circadian rhythm disturbances, and strains on family and social life.

Among the risks long work hours and shift work:

•Decline in mental function and physical ability, including emotional fatigue and a decline in the function of the body’s immune system  
•Higher rates of depression, occupational injury, and poor perceived health
•Higher prevalence of insomnia among shift workers with low social support
•Increased risk of illness and injury
•Increased risk of long-term health effects, such as heart disease, gastrointestinal disorders, mood disturbances, and cancer
•Reduced productivity
•Increase in errors
•Absenteeism and presenteeism (present at work but not fully functioning because of health problems or personal issues)  
•Increased health care and worker compensation costs
•Vehicle crashes
• Industrial disasters

Recommendations for improving sleep levels include:

•Workers should have ten consecutive hours per day of protected time off-duty in order to get 7-8 hours of sleep.
•Frequent brief rest breaks (e.g., every 1-2 hours) during demanding work are more effective against fatigue than a few longer breaks.
•Shift Lengths: Five 8-hour shifts or four 10-hour shifts per week are usually tolerable. Depending on the workload, twelve-hour days may be tolerable with more frequent interspersed rest days. Shorter shifts (e.g., 8 hours), during the evening and night, are better tolerated than longer shifts.
•Training: Provide training to make sure that workers are aware of the ups and downs of shiftwork and that they know what resources are available to them to help with any difficulties they are having with the work schedule.
•Avoid heavy foods and alcohol before sleeping and reduce intake of caffeine and other stimulants several hours beforehand since these can make it difficult to get quality sleep.
•Exercise routinely, as keeping physically fit can help you manage stress, stay healthy, and improve your sleep.

To read the complete blog post, which includes more tips as well as details on ongoing NIOSH research into reducing the risks associated with long working hours and shiftwork, go to:

Dr. Caruso is a research health scientist in the NIOSH Division of Applied Research and Technology. Dr. Rosa is the NIOSH Deputy Associate Director for Science.