Sleep Duration Strongest Predictor of Health Risk in Obese Teens?
Thursday, March 20, 2014
If you had to guess the strongest predictor of cardiometabolic health risks in obese teenagers, most of us would probably suspect their diet, sedentariness, or even mental health issues around mood, body image, or self-esteem.
Few of us would have guessed sleep duration.
But this is exactly what was found by Paul Gordon and colleagues from the University of Michigan, in a study published in the Journal of Pediatrics.
Although relatively small (the study included just 37 participants aged 11-17), the researchers went to great lengths to objectively measure habitual physical activity and sleep patterns as well as a wide range of cardiometabolic risk factors.
Amongst all of the measured variables, total sleep time and sleep fragmentation were inversely and independently associated with metabolic risk – the shorter the sleep time, the greater the risk.
This relationship remained robust even when the data were adjusted for various measures of physical activity, anthropometry, and adiposity.
Most subjects slept about seven hours a night, typically waking up at least once, with only five subjects getting the minimum recommended 8.5 hours of sleep each night.
Given what we now know about the profound impact of sleep deprivation on metabolism, physical activity and eating behaviours, it is astonishing that so little attention is being paid to the issue of sleep both in the public discourse of obesity as well as in clinical management of excess weight.
As I have said before, the three key drivers of obesity in my view are lack of time, lack of sleep and increased stress – everything else is either a consequence of or compounded by these factors.
Is it time for doctors to begin handing out sleep prescriptions?
@DrSharma
Edmonton, AB
Thursday, March 20, 2014
In discussions of sleep it amazes me how few people approaching the problem from topics other than melatonin production consider the problem of non-amber night lights and equipment lights.
As a very ancient hormone melatonin serves a great many functions, even helping with some opposing functions in the pancreas, and in the destruction of early tumor cells.
Perhaps the inclination to think of light as good causes people to forget that darkness also is good. Darkness is required to produce melatonin. Specifically, it is important to not have blue or green light, with blue wavelengths the most disruptive. Yet, think in the last decade and more how many equipment lights and night lights produce green light.
The least disruptive light for melatonin production is amber.
For some computers there even are programs now to allow the screen color to become more amber at night and bluer in the morning. That makes sense.
When you how much light you are feeding right into the eye from computers, pads, tv, games, lighting etc. instead if allowing a more natural reduction in lighting it becomes obvious why for some it is hard to get sleepy with lighting conditions so different from the natural even though natural lighting affects melatonin production and therefore many other endocrinological interactions and health functions beyond affecting sleep.
If equipment lights or non-amber night lights are in the room, and the teen does not sleep in an eye mask then it biochemically can be harder to stay asleep due to low melatonin levels.
It would be interesting to know how many of the kids who are unable to sleep are simply not producing enough melatonin to get sleepy and stay asleep because of lights.