Last night, many people (myself included) tuned into 60 minutes to watch the interview with Dennis Quaid and his wife about the hospital error that almost killed their newborn twins last year. It’s another segment, however, on sleep deprivation which caught my eye and is also getting a lot of buzz today on internet message boards.
In the recent 60 minutes episode called The Science of Sleep, Part 2, correspondent Lesley Stahl opens by announcing an interesting statistic – Americans report receiving an average of 6.7 hours of sleep, down from 8 hours in less than a generation. Stahl interviewed Eve Van Cauter, an endocrinologist at the University of Chicago School of Medicine, who studies the effect of sleep on the body (excerpt from CBSnews.com):
At [Cauter’s] lab, healthy, young volunteers…are paid to come one at a time and have virtually every system in their bodies monitored while their sleep is interfered with.
“We did a study where we restricted sleep to four hours per night for six nights,” Van Cauter explains. “And we noticed that they were already in a pre-diabetic state. And so, that was a big finding.”
The study’s subjects were on the road to type 2 diabetes in just six days, and that’s not all – they were also hungry. Van Cauter has made a radical discovery: that lack of sleep may be contributing to the epidemic of obesity in this country through the work of a hormone called leptin that tells your brain when you’re full.
“We observed that the volunteers, they actually had a drop in leptin levels,” Van Cauter explains. “Leptin was telling the brain, ‘Time to eat. We need more food.'”
Van Cauter’s research is new in that it demonstrates a correlation between the lack of deep sleep – to be distinguished from REM or light sleep – and health issues. In fact, says Cauter, as we age naturally, we automatically spend less and less time in deep sleep. This raises an interesting question about the diseases – such as high blood pressure, high cholesterol – that we normally associate with aging. It also sheds light on a possible cause of type 2 diabetes and obesity in younger adults, teens and children, all of whom, Cauter says, are receiving less and less sleep.
Cauter agreed with Stahl that health experts should add ‘sleep’ to their normal mantra of ‘diet and exercise.’ When asked about napping, Cauter says there is debate on whether not getting 8 consecutive hours of deep sleep or napping to increase the cumulative time spent sleeping is more important for preventing health problems.