Oprah Winfrey recently joined Dr. Oz in a “digital health care partnership” and among the topics they broached was a “healthy amount of sleep.”
As studies have confirmed, including one just released in France, not only does one’s amount of sleep matter, but also when one takes it. The study out of France followed workers who toiled late-afternoon and evening shifts, meaning they usually got to sleep after midnight — sometimes in the morning hours. The volunteers were then given cognitive tests to gauge any deleterious effects.
After studying 3,232 workers, the researchers identified 1,484 of them who had slept irregular hours. Among those who worked irregular hours for a decade or more, tests showed that they had experienced the equivalent of 6.5 years of “normal age-related cognitive decline,” regardless of their real age.
Even those who averaged only 50 days a year on irregular job shifts experienced the equivalent of 4.3 years of cognitive decline.
The standard for judging irregular hours was being forced to go to sleep after midnight or being forced to arise before 5 a.m.
The authors of the new study observed that messing with one’s circadian rhythm can cause “physiological stress, which has been shown to have an impact on brain structures involved in cognition and mental health.”
If you work irregular hours as described above, once you go back on a day shift, your cognitive functions will return to full power — but it can take up to five years!
Previous studies of irregular sleep patterns have shown the same effects on cognitive functioning.
The lesson here, for those of us who voluntarily choose to keep weird hours, is “don’t.” For those with shifts that interrupt your sleep, you may want to seek better hours or jobs. And if, in general, you have trouble sleeping, then you should seek professional help.
Regardless of the cause of irregular and/or deprived sleep, the result is directly tied to your brain power. That should be alarm enough to get you moving.