And now a team of researchers find that "social jet lag" may also be linked with higher obesity rates.
Most people know the feeling of dragging yourself out of bed in the morning and feeling wiped out periodically (or chronically) throughout the day. Many of us even have trouble falling asleep at night, as it seems harder and harder to put the cell phone down or turn off the computer.
Researchers have come up with a new term for our skewed sleep-wake cycles: Social jet lag. And it could be responsible for more health issues than just feeling tired from time to time.
People who were more socially jet lagged were more likely to have higher body mass indices (BMIs) than others.
Social jet lag refers to the fact that the schedules we keep are fundamentally out of sync with our internal clocks, which, along with the sun's movements, cue us to wake and sleep at certain times of the day.
It's a 24/7 world, and by staying up late, spending more time in darkness, we delay our bodies' clocks. More and more evidence is linking the disruption of our internal or biological clocks to serious mental and physical health problems. The researchers found that in 70% of the population, biological and social clocks differ by more than one hour.