0720 GMT March 22, 2018
Insufficient sleep has been recognized by the Centers for Disease Control and Prevention (CDC) as a major public health concern. It is currently estimated that between 50 and 70 million people in the United States have a sleep disorder, and one analysis revealed that over a third of adults do not get enough sleep.
Sleep deprivation leads to traffic accidents and occupational errors that can, in turn, cause industrial or environmental disasters.
Additionally, sleep deprivation has many adverse health effects. According to the CDC, not getting enough sleep may lead to a range of chronic diseases such as diabetes, obesity, or cancer, as well as generally increasing the risk of dying prematurely.
Finally, a lack of sleep simply makes us unhappy. Insufficient shuteye reduces the quality of life, productivity, and may even lead to depression.
New research by scientists at the University of Warwick in the United Kingdom underscores the importance of sleep for public health, and suggests that improving our sleep quality can make us as happy as winning the lottery.
The study, published in Sleep, was led by Dr. Nicole Tang, of the Department of Psychology at Warwick.
Dr. Tang and colleagues examined the sleep patterns of 30,594 people over the age of 16 in the U.K. across a period of 4 years: sleep quality and well-being were assessed once between 2009 and 2011, and again between 2012 and 2014.
The variables analyzed were sleep quantity, sleep quality, and the use of sleep medication. The outcomes researchers looked at were health and well-being.
To measure these outcomes, the team used the General Health Questionnaire (GHQ) as well as the mental and physical component scores of the 12-Item Short-Form Health Survey (SF-12) - a scale commonly used to assess health-related quality of life.
Using linear regression models on each outcome, the scientists adjusted for potential factors that may influence the results. Some of these confounding variables included sex, age, and ethnicity, as well as education and employment status.
The researchers found that insufficient sleep or poor quality of sleep can worsen medical conditions and emotional states.
Interestingly, the use of sleep medication was also linked with these adverse effects.
Improvements in sleep quantity and quality, as well as using less sleep medication, were found to correlate with higher scores on the GHQ and the SF-12 scales. In fact, the researchers found a 2-point improvement in the GHQ score, which is the equivalent of an 8-week program of mindful cognitive therapy aimed at improving psychological well-being.
As the researchers note, the score improvements were also comparable with the average increase in well-being measured in lottery winners 2 years after a $250,000 jackpot win.
Overall, improvements in sleep quality accounted for the largest beneficial effects on health and well-being, suggesting that the quality may be more important than the quantity of sleep we get.
Dr. Tang advocates promoting the reduction of sleep medication and improvement of sleep quality as public health values, and underscores the importance of improving sleep behaviors for the health and happiness of the general population, not just those with acute sleep disorders.
"The current findings suggest that a positive change in sleep is linked to better physical and mental well-being further down the line. It is refreshing to see the healing potential of sleep outside of clinical trial settings, as this goes to show that the benefits of better sleep are accessible to everyone and not reserved for those with extremely bad sleep requiring intensive treatments."
Additionally, Dr. Tang notes that improving sleep quality can be a cost-effective and simple way of increasing well-being on a societal level.
The lead author concedes that the study is purely observational and does not prove a causal link between sleep and happiness. She also indicates areas for future research.
"An important next step," Tang says, "is to look at the differences between those who demonstrate a positive and negative change in sleep over time, and identify what lifestyle factors and day-to-day activities are conducive to promoting sleep. Further research in this area can inform the design of public health initiatives."