Is sleep essential for life? In 1978, a pioneering sleep researcher wrote "If sleep does not serve an absolutely vital function, then it is the biggest mistake the evolutionary process has ever made." Today, current sleep scientists have verified that this was not an evolutionary error and that sleep is a fundamental, irreplaceable biologic process for all animals, not just humans. Research shows that sleep in humans serves critical roles in optimizing brain function including memory, mental and physical performance. The requirement for sleep has been recognized in popular genre as well. This was illustrated in an episode of Star Trek, the Next Generation in which the crew of the Enterprise begins to become paranoid from the lack of REM sleep. Furthermore, the health impact of the lack of sleep is becoming increasingly apparent. Insufficient sleep is a risk factor for the development of heart disease, high blood pressure, diabetes mellitus, obesity, depression and earlier death.
In the last 30 years in the United States, the average sleep duration has decreased and the percentage of adults sleeping less than six hours per night has increased. If sleep is vital for life, why do people in today's society try to get less of it? A number of explanations have been proposed including greater use of artificial lighting, the impact of a 24 hour non-stop society and the need for higher work productivity. Most recently, the use of electronic devices, especially those emitting blue wavelength light, to read, text or sent email at night has been implicated as a cause of sleep disturbance.
The role of sleep in promoting a healthy society has been recognized by the US Department of Health and Human Services in their Healthy People 2020 initiative. One of its objectives is to "increase the proportion of adults who get sufficient sleep". Of course this begs the question of how much sleep is sufficient. Unquestionably, the sleep needs of individuals exhibit some variability, but is there some minimum amount of sleep that should be the target for all adults? This latter uncertainty was addressed recently in two recent consensus statements, one from the National Sleep Foundation and the other from the American Academy of Sleep Medicine (AASM) and the Sleep Research Society (SRS). The latter two organizations are the leading scientific and professional organizations representing sleep medicine clinicians and researchers. Both statements recommended a minimum of seven hours of sleep for optimal health. As an author of the AASM/SRS document, I was impressed that there was remarkable agreement among conferees that at least seven hours of sleep was the best recommendation and that lesser amounts of sleep were associated with poor health outcomes.
Given the unanimity that adults should get at least seven hours of sleep per night, how can individuals and society as a whole achieve this goal? As a first step, individuals need to make sleep a priority in their life. This means setting aside an adequate amount of time to sleep. For example, if the choice is to watch a late night television show versus sleep, consider recording the show for later viewing and then going to sleep. In addition, individuals need to encourage their family and others to get more sleep. As a society, we should no longer assign high value to the ability to stay up and work late into the night. Performance under such circumstances suffers, and hence net productivity declines rather than improves. Instead, employers should promote workplace policies that facilitate healthy sleep habits such as discouraging use of email at night and overtime shifts that reduce sleep opportunities. In addition, they need to help educate their employees about the benefits of adequate sleep. They should realize that there is a potential triple bottom line benefit to having a healthy sleep workplace:
1. Improved employee productivity related to better mental and physical performance;
2. Lower health care costs from healthier employees;
3. Greater workplace safety from fewer accidents.
Adequate amounts of sleep are essential for optimal health. Sleep is inexpensive, does not require a visit to the doctor and has no side effects. If, as individuals and a society, we place more value on obtaining sufficient sleep, we will eventually be healthier, happier and more productive. Let this be our collective goal.