What is Jet Lag and How Does it Affect us?
Jet lag is a common occurrence when you travel across multiple time zones; your body attempts to adjust to its new schedule, but your circadian rhythm may still be back in the country where you left it.
Our bodies are programmed to follow a 24-hour schedule, which is often referred to as our body clock. Our body clock regulates our sleeping, eating, body temperature and other biological patterns and functions, so when this is disrupted, we experience unpleasant symptoms.
Our body clock adjusts based on external cues, such as daylight. When it gets dark in the evenings our bodies produce more melatonin1, a hormone that increases drowsiness and lowers body temperature, causing us to fall asleep when our bodies are ready.
Now, imagine your body clock has been following a routine for a week, a month, or even years – it expects to perform certain activities at times when it knows it needs to rest, sleep, or even be alert. Jet lag is caused when this routine is disrupted.
You wake up as normal for your flight at 8am and you are on a plane for 12 hours – when you reach your destination, your body is likely to be ready for rest or sleep, however, it is only 2pm at your destination which would not be a common time to go to sleep. Forcing your body out of its routine or natural body clock causes symptoms, such as fatigue which, in turn, can cause stress and agitation.
What Causes the Effects of Jet Lag?
Combatting the effects of jet lag may seem like a tough task, however, research studies have shown ways around jet lag, and why travelling in certain directions may make jet lag better or worse for your body.
Using a mathematical model, scientists2 have discovered a way to show that our brain cells can respond differently depending on the direction that you’re travelling in. The brain cells that regulate our circadian rhythm are called neuronal oscillator cells; when these cells can’t adjust to our new time zone in a reasonable response time, our metabolism, sleep patterns and other factors are effected, also known as jet lag3.
When travelling East, our neuronal oscillator cells don’t commit to a 24-hour schedule which our body is used to. Without any external cues, the cells activity performs a slightly longer cycle of around 24.5 hours. Therefore, it is easier for our bodies to extend the length of the day by travelling West, rather than shortening it by travelling East.
Previously, the advice most travellers would be familiar with is to base one day of recovery per time zone crossed. The model created by physicists from the University of Maryland shows that a person crossing three time zones, travelling West, will take on average under four days to recover; aligning with what we already know. However, people travelling East can take on average more than four days to recover from crossing three time zones, because of the slightly longer cycle of 24.5 hours.
Some people may have a naturally longer circadian rhythm, so they may not experience the extreme effects of jet lag compared to others; the research has not been physically tested as of yet, however, the predictions are based on a mathematical formula in order to help people manage their expectations when they travel.
How to Combat the Effects of Jet Lag
Although there is no possible way to prevent jet lag, you can effectively train or trick your body into a new schedule which can lessen the symptoms of jet lag.
Establish a new routine
When you reach your new time zone, you’ll want to establish a new routine pretty quickly; eating and sleeping at the ‘normal’ times for the time zone you’re in is recommended. This way, your body will continue to follow its usual 24-hour schedule, but you’ll be shifting activities into new time slots. After a few days, your body will get used to its new routine and you’ll feel just as you would at home.
We don’t want you to avoid sleeping altogether, and after a long trip it’s natural to feel tired, especially as the likelihood of experiencing full rest on a plane is very slim. However, try and power through the urge to nap or sleep – you’ll want to stay active until it’s the correct time to sleep for new time zone. This will allow your body to adjust more quickly, and after a couple of good nights’ sleep (at the right time), you’ll feel right as rain.
Natural daylight is one of the most powerful tools to reset your internal clock, getting you back on the right path for your new 24-hour schedule. When you reach your new time zone, allow your body to absorb as much daylight as possible. Whether you’re exposing yourself to sunlight during the daytime, or opening a window, natural sunlight will help you adjust to the new time zone.
Avoid alcohol & Caffeine
In order to fall into your new routine in the most natural way possible, you’ll want to avoid any stimulants or depressants that could interfere with your ability to fall asleep, stay asleep, or even stay awake (dependant on your new time zone). It’s quite common for passengers to resort to caffeine or alcohol whilst on a long plane journey, but it’s recommended to avoid it, or minimise your consumption as much as possible, to ensure a natural transition.
As we know, melatonin is a hormone that regulates bodily rhythms – in medication form, melatonin can be used to re-align those rhythms4. For those travelling East or across five or more time zones, melatonin can be remarkably effective in reducing the symptoms of jet lag.
If, you’re still struggling to get some quality shut eye, then maybe the problem lies beyond jet lag. If you can’t remember when you last changed your mattress, then it’s likely that this is the underlying problem; jet lag is just enhancing this issue.
Take a browse through our mattresses and treat yourself to a good night’s sleep every night of the week; you need it!
If you’d like to learn more about all things sleep-related, take a look at a few of my other blogs below.
1. Costello RB et al. (2014) The effectiveness of melatonin for promoting healthy sleep: a rapid evidence assessment of the literature Nutrition Journal 13:106
2. Lu Z et al. (2016) Resynchronization of circadian oscillators and the east-west asymmetry of jet-lag Chaos 26, 094811
3. Herxheimer A (2014) Jet lag BMJ Clinical Evidence Apr 29;2014 pii:2303
4. Herxheimer A & Petrie KJ (2009) Melatonin for the prevention and treatment of jet lag Cochrane Database of Systematic Reviews Issue 3. Art. No.CD001520