Jet-lag according to science
Anyone who has never at least one had to deal with Jet Lag symptoms, please raise your hand!
The “Jet-Lag Syndrome” defines a set of disorders that affects travellers who go through multiple time zones, generally during an intercontinental flight.The human body is synchronised on a 24-hour sleep-wake balance, set by the succession of day and night, on which we base our daily schedules. What we call “internal clock” is scientifically defined as circadian rhythm and it isn’t that flexible – which is why, when we disrupt it, we experience discomfort and disorders, such as those associated to Jet Lag.
The circadian rhythm
The circadian rhythm is a complex mechanism setting our biological schedules in line with our surrounding environment.
Our “internal clock” is a purely genetic issue: by isolating the relevant genes and studying the molecular mechanisms of their functioning, they were able to explain in-depth the functioning of the biological clock of every one of us, the so-called “chronotypes”: the “bears”, who sleep between 11 pm and 7 am and are better able to adapt their rhythm to that of the external world; the “night owls”, who tend to postpone the time dedicated to sleep; the “early birds”, the morning people, who tend to fall asleep and wake up before the reference time.
The symptoms will be more intense if you travel from West to East, because it is easier for our body to extend the circadian rhythm rather than reducing it.
Jet Lag: what is it exactly
Jet-lag symptoms arise when our circadian rhythm is “disrupted” by a set of events that require adjusting to the new light/dark times. This entails a series of physiological reactions, among which: altered hormone secretion, changes in blood pressure and in some flow parameters, such as the increase of cortisol, the hormone of stress. The intensity of symptoms is not the same for everyone, but varies according to age, usual sleep hours and chronotype.
Jet-Lag symptoms, prevention and treatment
The main problems caused by the jet lag concern sleep troubles, like insomnia, sleepiness during the day, or the feeling to not have rested when waking up. These symptoms go with a set of side troubles, such as:
- Headache
- Confusion
- Trouble focusing
- Excessive fatigue
- Involuntary contractions when dreaming
- Scarce salivary secretion
The duration of this symptoms changes according to several factors: number of time zones crossed when travelling, travel direction, age and general health conditions, hydration.
Before you set out for a long trip, you may resort to some helpful tricks to help you prevent or reduce the Jet-lag Syndrome:
- Get to the trip well-rested, without accumulating hours of sleep deprivation
- If you’re travelling West, it’d be good to go to bed a few hours earlier than usual on the days before the departure;
- If you’re travelling East, it’d be good to go to bed a few hours later than usual, however without excessively reducing the total sleep hours;
- Keep hydrated before and during the trip;
- Once at your destination, avoid alcohol and caffeine, as these substances naturally alter the sleep-wake balance;
- Choose foods that contain melatonin, which improves the quality of sleep: oat, corn, cocoa, almonds, cabbage, tomatoes, apples, oranges, and pineapple.