Sleep is an integral part of our overall health, and if it is disturbed, it can increase the risk of health complications.
What is social jet lag?
Social jet lag is a term coined to define those who have weekend sleep schedules that differ from weekday sleep schedules. This can be due to social commitments, which can keep you up late and cause you to sleep in much longer than you normally would.
It is estimated that two-thirds of the population are affected by social jet lag. Dr. Till Roenneberg is the individual who coined the term ‘social jet lag’ and explained that changing sleep schedules from weekday to weekends can be similar to changing time zones. He explained, “The behavior looks like if most people on a Friday evening fly from Paris to New York or Los Angeles to Tokyo and on Monday they fly back. Since this looks like almost a travel jet lag situation, we called it social jet lag.”
The main difference between social jet lag and flying jet lag is light. When you arrive in a different country the sun is either rising or setting, so your body’s natural clock (circadian) will begin to reset itself. With social jet lag you are in the same place, so the reset does not occur.
Weekday sleep changes: Social jet lag raises diabetes and heart disease risk
It has been found that individuals on shift work are more likely to develop metabolic syndromes, coronary heart disease and diabetes compared to those with regular working schedules. This can be due to shifts in their circadian rhythm.
Patricia M. Wong, M.S, from the University of Pittsburg said, “Social jet lag refers to the mismatch between an individual’s biological circadian rhythm and their socially imposed sleep schedules. Other researchers have found that social jetlag relates to obesity and some indicators of cardiovascular function. However, this is the first study to extend upon that work and show that even among healthy, working adults who experience a less extreme range of mismatches in their sleep schedule, social jetlag can contribute to metabolic problems. These metabolic changes can contribute to the development of obesity, diabetes and cardiovascular disease.”
Researchers examined sleep schedules of 447 men and women between the ages of 30 and 54. Participants wore a wristband to monitor movement and sleep over the course of seven days. Questionnaires were used to determine the lifestyle habits and diets of the participants.
Nearly 85 percent experienced a later halfway point in their sleep, known as midsleep, on their free days (non-work days). Fifteen percent had earlier midsleep.
Those with greater sleep misalignment had worse cholesterol profiles, higher fasting insulin levels, larger waist circumferences, higher body mass indexes and were more resistant to insulin compared to those with lesser social jet lag.
Wong added, “If future studies replicate what we found here, then we may need to consider as a society how modern work and social obligations are affecting our sleep and health. There could be benefits to clinical interventions focused on circadian disturbances, workplace education to help employees and their families make informed decisions about structuring their schedules, and policies to encourage employers to consider these issues.”
Sleep deprivation and your risk of cardiovascular disease and diabetes
A 2011 study found that out of 475,000 people, 48 percent of those with shorter sleeping lengths were at a higher risk of dying or developing coronary heart disease, compared to those who received proper amounts of sleep. Additionally, too much sleep also negatively affects your health. Those who received over nine hours of sleep increased their risk of heart disease by 38 percent. This suggests that sticking with seven to eight hours a night is a good way to help protect your heart.
Sleep is also important for diabetes risk; research has shown that those who do not receive adequate sleep feel more tired, which in turn prompts them to consume more comfort foods. Furthermore, our hormones become regulated as we sleep to control weight, appetite and even protect our immune system. Therefore, a lack of sleep can throw all those aspects of our health out of whack, increasing the risk of diabetes.
Social jet lag and obesity
One study from the University of London in the UK, Duke University and the University of North Carolina in the U.S., and the University of Otago in New Zealand examined 815 non-shift workers through cross-sectional analysis from a cohort study. The goal was to uncover associations between metabolic markers that indicate obesity-related diseases and social jet lag.
Unlike jet lag from air travel, which is temporary, social jet lag can become a chronic problem in a person’s life, increasing the risk of negative health consequences.
The researchers found that those with higher sleep discrepancy were also found to have higher body mass indexes (BMI). Although the research does not reveal cause and effect, it does suggest that social jet lag may contribute to obesity.
Tips to avoid social jet lag
- Wake up at the same time every day – including weekends – regardless of when you went to bed.
- Ensure your office has good natural light or find a job that allows you to be outside – we are more awake when there is natural light.
- Get sunlight exposure first thing in the morning, to help you wake up.
- Avoid bright screens prior to bed.
- Try scheduling social activities earlier in the day.
- Avoid caffeine in the afternoon.
- Exercise regularly.
- Have an early, light dinner.
- Create a soothing bedtime routine.