Waking up early on workdays – only to sleep on your days off – is a common practice. While it can seem intuitive to rest, experts in this report by SADE OGUNTOLA, say oversleeping on days off may be inimical to health.
In many big cities, many people wake up early, say, 4 am, to get to work by 8am, but on the weekends, they will want to sleep in. But the cost of delaying sleep till Saturday and Sunday is much greater than many people may think.
Lack of sleep—especially on a regular basis—is associated with long-term health consequences, including chronic medical conditions like diabetes, high blood pressure, and heart disease, and these conditions may lead to a shortened life expectancy.
In a new study, researchers said that sleeping in on weekends to catch up with sleep deficit, what is now termed social jet lag, is connected with poor health, bad mood, and increased sleepiness and fatigue.
It doesn’t boost energy levels. In fact, they said that it has the opposite effect. It disrupts the body’s internal clock so much that just a few extra hours makes a person feel even more tired than normal on Monday morning.
Could weekend lie-in kill?
The preliminary analysis of the study reported at SLEEP 2017, the joint annual meeting of the American Society of Sleep Medicine and the Sleep Research Society that each hour of social jet lag is also related to an 11 per cent increase in the likelihood of heart disease.
These effects are independent of the duration of the sleep and insomnia symptoms, which are associated with both social jet lag and health.
Sleeping in on weekends, a common habit
Sleeping in on weekends is a luxury that seemingly many people assume would translate to a net positive for health, rather than a negative.
But “the disruption of the body’s circadian clock due to late night bedtimes followed by later weekend wake times when it is habitual takes toil on health, including the mood, emotional state and working of the organs in the body,” said Dr Kolawole Mosaku, a consultant psychiatrist, Obafemi Awolowo University Teaching Hospital Complex, Ile-Ife, Osun State.
Sleep rejuvenates the body but late-night bedtimes followed by later weekend wake times alter this body repairs. “The body works like a clock and the moment the clock is not obeyed, it will take toll on all aspects of health,” Dr Mosaku said.
He declared, although the heart, for instance, pumps blood around the body all through the day, its function is also based on substances produced by other parts of the body, whose production may be affected by a poor sleep pattern.
Good-quality sleep decreases the work of the heart, as blood pressure and heart rate go down at night.
How much sleep do we need?
Dr Mosaku said there is evidence suggesting that sleep regularity, beyond sleep duration alone, play a significant role in overall health, adding that the body needs a minimum of six hours of sleep regularly to rejuvenate itself and function actively.
He, however warned that people that sleep in on weekends to catch up with sleep deficit could also wake up fatigued.
“Usually when sleeping in on weekends to catch up with sleep deficit is habitual, the person may wake up tired. The tiredness is an indication that the body is already reacting to the disruption in its circadian clock and not recovering as is expected,” he said.
The medical expert, however, said the problems of social jet lag is similar to that experienced by night shift workers, adding “if a person is forced to be awake for one to two days, that is okay, but when it becomes a routine, then it creates a problem.”
In addition, despite the extra weekend sleep, some people, including long distant drivers still sleep while driving. Their ability to focus and pay attention is also reduced.
Dr Kazeem Adebayo a consultant psychiatrist, LAUTECH Teaching Hospital, Osogbo, Osun State declared that poor sleep habits like social jet lag are more prone to use of substances like coffee to keep awake, adding that such substances because of their additive tendency could further worsen their health status.
For the study, the researchers analysed data from the NIH-funded Sleep and Healthy Activity, Diet, Environment, and Socialisation (SHADES) study. It is a community-based survey of close to 1,000 adults between the ages of 22 and 60 that was conducted by the University of Pennsylvania Centre for Sleep & Circadian Neurobiology.
Social jet lag, represented in hours, was assessed using the Sleep Timing Questionnaire and calculated by subtracting weekday from weekend sleep midpoint.
Information given included age, sex, race/ethnicity, education, employment, income and sleep duration. Insomnia was measured with the Insomnia Severity Index (ISI).
After adjusting for race/ethnicity, income, education, employment, sleep duration, and insomnia, social jet lag was associated with poorer health, heart disease, worse mood, and increased sleepiness and fatigue.
With every hour of social jet lag, respondents were 22 per cent more likely to report that their overall health was “good” instead of “excellent” and 28 per cent more likely to say their health was “fair or poor” instead of “excellent.”
Another review of controlled studies on extended sleep finds that when adults sleep longer than normal, they tend to report increased fatigue, irritability and lethargy — possibly triggering the desire to sleep more and perpetuating a cycle.
Also reported are lower mood, slower reaction time, poorer mathematics performance and more fragmented sleep, which has several health implications as well.
Catching up on sleep really possible
Experts say the ultimate is getting back on a regular cycle of seven to nine hours of shut-eye per night. It can take days or even weeks for your body to return to a normal pattern.
So, treating sleep as a priority, rather than a luxury, may be an important step in preventing a number of chronic medical conditions.