The onset of diabetes and heart disease is more likely among those who experience social jet lag, by sleeping more during the weekend.
This warning has been issued by a team of researchers led by Patricia Wong, at the University of Pittsburgh. During a study, whose findings have been published on Wednesday in the Journal of Clinical Endocrinology & Metabolism, a group of 447 healthy people aged between 30 and 54 were carefully monitored.
Experts used Actiwatch-16 accelerometers developed by Phillips healthcare, in order to track each participant’s daily activity, with extra attention being given to sleep and wake patterns.
The experiment unfolded across 7 days, which included at least one night occurring before the weekend, in order to analyze what effects “social jet lag” would have on the subjects.
This phenomenon, whose name has been coined by Till Roenneberg, professor at the Institute of Medical Psychology at the University of Munich, refers to changes in sleep schedule which occur among some people during days off.
Approximately two-thirds of the population are believed to have this habit of sleeping in during the weekend, in order to compensate for too little sleep during work days. Moreover, they are much more likely to stay up later during the weekend, in order to socialize with friends and family.
In a study published in May 2012 in Current Biology, Roenneberg had shown that such sleep disruptions affect the circadian rhythm, and lead to a heightened risk of becoming overweight or obese.
Moreover, as the author explained, chronic social jet laggers are more likely to smoke, to drink excessive amounts of alcohol or coffee, or to suffer from depression.
Wong’s team wanted to test these preliminary findings, and that’s why researchers carried out their own trial, assessing the health effects of commuting one’s usual sleep routines to different ones.
They discovered that around 85% of the subjects had changed their usual patterns during the weekend, by sleeping at later hours and waking up later. In contrast, around 15% of them had done the opposite, by switching their sleep time to earlier hours.
The average shift in sleep habits was of around 44 minutes, although a few of the participants had altered their schedule much more significantly, shifting their resting time by approximately to 2 or 3 hours.
It was discovered that those who had modified their sleep routine the most were the ones more likely to have an elevated body mass index and to suffer from insulin resistance.
They also had lower levels of HDL “good” cholesterol, larger waist circumference, and higher concentrations of triglycerides in their blood.
Overall, the more they had strayed from their usual routine during weekends, by adopting inconsistent sleep patterns, the more they risked developing type 2 diabetes, as well as cardiovascular disease.
It’s the first time that a study proved the detrimental effects of social jet lag, by actually monitoring sleep and correlating it with health indicators.
Researchers believe that when resting periods shift, the circadian biological clock is perturbed, and metabolic processes no longer function properly, which leads to a string of harmful effects, such as inadequate food absorption, excessive fat buildup, and improper insulin production and secretion.
Therefore, they recommend that people shouldn’t change their routines so drastically during the weekends, and instead get enough rest during weekdays too, so that they can wake up just as early throughout the entire week.
The negative effects of regular sleep deprivation can’t be combated just by sleeping in during days off, and it appears that this strategy has numerous negative consequences in the long run.