Jet Lag: why it happens and how to avoid it?

Our bodies are ruled by the circadian rhythms, which regulate the physical and mental characteristics that we experience over a 24 hour cycle. They are controlled by a small area in the brain and one of its main tasks is to manage the sleep-awake cycle in accordance with the sun’s journey; they also rule our appetite, along with kidney and hormone functions such as melatonin and cortisol. Jet lag occurs when there is an imbalance between the internal and external factors due to crossing, normally, two or more time zones in a very short period of time. Our bodies cannot process this change quickly enough and it can take between two and six days to adapt to the new destination. 

Each person’s circadian cycles are different and their response to jet lag will depend, amongst other things, on how easily they go to sleep or their resistance to sleep deprivation. Each person’s sensitivity to light is also an influential factor, as well as the choice of their destination. Passengers travelling towards the east will be more likely to suffer from jet lag. This is due to the fact that when we travel towards the west, the body has to remain awake longer than normal. Most people have less trouble staying up all night than getting up early, that is to say, they already start out from a cycle that is extended beyond 24 hours. Other factors that increase the likelihood of suffering from jet lag range from the passenger’s age to the frequency of travelling and of course, the more time zones that are crossed, the greater the jet lag. 

Possible symptoms of jet lag

Depending on each person, Jet lag symptoms may be better or worse, in some cases experiencing one, several or none of the following: 

• Alterations in sleep patterns: Difficulty in going to sleep or waking up; interrupted sleep or fatigue during the day.
• Lack of concentration: A decrease in physical and mental performance.
• Digestive problems: Constipation, diarrhoea or vomiting, a decrease in the appetite.
• Mood swings: General malaise, irritability, stress or sadness, a decrease in attention-span and alertness.
• Dehydration: Headaches and excessive sweating.

How can the effects of jet lag be mitigated?
 

a) Before flying

• Plan the journey: Several factors must be taken into consideration in order to try to mitigate the effects of jet lag, such as knowing each person’s chronotype, the original and destination time zones, the time of the flight and where you are flying to. If you are travelling for work or for an event, it is better to arrive a few days beforehand to give your body time to get used to the new time schedule.
   
• Start to adapt yourself: Start the journey without any lack of sleep, resting sufficiently in the days before the trip. Before leaving, change your watch to the new time zone. It is a good idea to start changing sleep and meal times a few days before travelling.
   

b) During the flight

• Try to adapt yourself to your new time schedule: If it is daytime, try not to sleep until you reach your destination. If you land in the morning and it has been a night flight, try to sleep during the trip. If you find it difficult to sleep on planes, earplugs and a face mask might help. It is also advisable to adapt your mealtimes as much as possible.
   
• Look after your body: There is very little humidity in plane cabins and this can make the effects of the time schedule imbalance worse. Make sure you are well hydrated and avoid caffeine and alcohol, as well as other stimulating drinks. Stand up every now and again and walk along the aisles; this will help your circulation and oxygenate your muscles properly. Also take advantage of resting as much as you can and avoid foods that are difficult to digest.
   
• Shower at your stopovers: If your flight is not direct, you can shower at the airport; this will help you to fight the effects of tiredness.
   

c) Once at your destination

• Take into account your exposure to light: his is the most influential factor in the circadian cycles, as it is in charge of guiding the body, informing it of whether it is day or night-time. It is important to control exposure to it to help our internal clock to readapt itself.
   
• Control what you eat: If you are prone to suffering from stomach pain, it is better to eat small, light meals.
   
• Melatonin: It plays a key role in the management of your body’s biorhythms and therefore exposure to strategic light can help to get to sleep, as it is a hormone that the body generates when it detects darkness. If jet lag still prevents you from sleeping, you can take melatonin supplements before going to bed, after consulting your health specialist.
   

In short, although the effects of jet lag are temporary, they can cause great discomfort and can affect the start of your holiday. Therefore, it is worth taking note of their importance and reading up on them, getting ready before embarking on transoceanic flights to minimise their effects and enjoy the journey as much as possible.