JET LAG: SYMPTOMS, TREATMENTS AND PREVENTION

Symptoms

For further information: Jet lag symptoms

The disorganization of the internal biological clock (which also regulates the alternation between sleep and wakefulness) with respect to the new light / dark periods, determines a series of disturbances which, taken together, are called "time zone syndrome".

If the trip involves crossing at least two time zones, the first symptoms of jet lag usually begin within one or two days of departure. The main symptoms of jet lag can be:

diurnal asthenia (tiredness and fatigue during the day);

lack of appetite;

general ill feeling: nausea, headache, muscle soreness;

sleep disturbances, linked to an imbalance in the secretion of melatonin: excessive sleepiness, insomnia, difficulty falling asleep;

reduced physical and mental performance: difficulty concentrating or carrying out normal activities, reduced or altered mood, irritability, nervousness;

changes in gastrointestinal function: digestive problems, stomach upset, constipation or diarrhea.

It is calculated that, in order to adapt the circadian rhythm to the new time, approximately 60 or 90 minutes should be recovered every day, with respect to the change in time zone:

From west to east. Adaptation to the new time zone requires, in days, about two thirds of the number of time zones crossed (hours of difference between the departure and arrival time zones). Example: Changing your 12-hour time zone east requires 9 days to adjust.

From east to west. Jet lag leads to disturbances lasting, in days, about half the number of time zones crossed. Example: Changing your 12-hour time zone to the west takes approximately 6 days of biological synchronization.

It can take a few days for our biological clock to fully adjust to the new circadian rhythm. The duration of the disturbance can reach a maximum of 7-10 days for trips to the east that involve crossing 8-12 time zones.
Since the days affected by Jet lag could affect the total duration of the trip, instead of waiting for the "organism to get used to it" naturally, it is possible to intervene in advance to prevent the disturbance and prepare for the new circadian rhythms, adopting some behavioral precautions.

Travel fatigue and jet lag.
"Travel fatigue" is associated with a condition of general fatigue, disorientation and headache, which does not necessarily involve an "alteration of circadian rhythms. This condition is determined by a change in routine and by the time spent in a confined space, with little possibility to move during the trip. The tiredness of the trip can be felt even without crossing time zones and the recovery is rather short: a couple of days of rest and a balanced diet are enough. Jet lag, on the other hand, causes more persistent symptoms and recovery can last up to a week.