As if you didn’t already have enough reason to hate your alarm clock, a study indicates that being jarred awake by a blaring alarm may be a contributing factor to obesity. The theory runs that because our natural biological clocks are being interrupted, our bodies respond in a variety of ways leading to increased rates of obesity.
The study, published by chronobiologist Tim Roenneberg of the University of Munich in the May 2012 issue of Current Biology, specifically identified the effect of alarm clocks as “social jetlag.” The study complied data from an Internet survey which netted tens of thousands of responses from participants aged 16-65.
Our bodies, says Roenneberg, follow their own natural biological clock. This clock is set by daylight exposure, time of year, and internal factors. It determines when we get tired and, crucially, when we should wake up. The problem is, most of us don’t wake up when we want to – especially on weekdays. How far off are we? Roenneberg states that 70% of the population has a discrepancy between their biological clock and their social clock of at least one hour.
Previous data revealed that starting your day at social jetlag tends to lead to a higher intake of caffeine, nicotine, and alcohol. But how does it affect weight?
If you are already of normal body weight, then social jet lag is not a significant cause of obesity. But don’t relax yet: if you are already overweight or tend to pudginess, then higher levels of social jet lag do lead to higher levels of obesity.
This is due to a number of factors, according to Roenneberg. One, unsurprisingly, involves eating: “eating at the wrong time hits your entire digestive system at the wrong time, so it cannot efficiently do its job.” This is often the case on workdays when the body wakes up before it is ready. When we eat our breakfast, our bodies think it is still night time. The body is not ready to process the food optimally.
Unfortunately, research also indicates that the problem is getting worse. The underlying cause of social jetlag is receiving less outdoor light and generally basing our sleep hours more on convenience than on what our bodies tell us. These factors have increased from 2002 to 2012, with survey participants indicating that they wake and sleep 20 minutes later during that time.
It is possible to reset your biological clock, and un-social jetlag yourself. Getting more natural light helps to sync your body to the natural circadian rhythm. Going to bed and waking up at the same time every day also helps to establish sleep regularity. This means not skimping on sleep on weekdays, followed by bed binges on weekends.
Aside from the Monday to Friday working crowd, sleep issues that can lead to social jet lag are also often associated with shift work, graveyard shifts, and college students.
In order to avoid these risks, the answer is not to throw away your alarm clock. Instead, try to get more natural light, avoid sleeping in excessively on weekends, and, most importantly, go to bed when your body tells you to.