As if we didn’t have reason enough to get a good night’s sleep, researchers have discovered two more. A study in May issue of the journal Sleep finds that lack of sleep is linked to early death, while another article, in the June issue of Journal of Clinical Endocrinology & Metabolism, reports that just one night of sleep deprivation ups insulin resistance, which is linked to type 2 diabetes and metabolic disease.
The researchers suggest that lack of sleep may cause problems in levels of the hormones associated with appetite and satiation, leading to over-eating and lack of activity, and ultimately to metabolic and cardiovascular issues.
The team in the first study, based at Federico II University in Naples, Italy, reviewed 16 earlier studies that looked at duration of sleep and mortality. Combining all the data from these earlier works yielded a group of over 1.3 million participants who had all been questioned about their sleep habits. Of these, 112,556 died during the course of their respective studies. Francesco P. Cappuccio and his team found that getting fewer than six hours of sleep was linked to early death – in fact, shortened sleep raised the risk of dying prematurely by 12%. The researchers suggest that lack of sleep may cause problems in levels of the hormones associated with appetite and satiation, leading to over-eating and lack of activity, and ultimately to metabolic and cardiovascular issues. They also point out that “low grade inflammation is activated during short sleep, with possible implications not only for cardiovascular disease but also for other chronic conditions including cancer.”
The [second] study’s results may also have relevance to the increasing frequency both of diabetes and sleep deprivation in today’s world.
Donga and her team write that their findings “indicate that insulin sensitivity is not fixed in healthy subjects, but, rather, depends on the duration of sleep in the preceding night.” They add that the “current study and others...indicate that shortened sleep duration is a factor that contributes to glucose intolerance and, even after a single night, to insulin resistance.”
The study’s results may also have relevance to the increasing frequency both of diabetes and sleep deprivation in today’s world. In fact, Donga says in an Endocrine Society press release that "[t]he co-occurring rises in shortened sleep and diabetes prevalence may not be a coincidence. Our findings show a short night of sleep has more profound effects on metabolic regulation than previously appreciated."
Clearly sleep is important not just for our psychological health and well-being, but it plays an important role in our physical health and longevity as well.