1. The Circadian Rhythm Defines More than Just Our Sleeping Pattern

Every animal and human being has a circadian rhythm (‘around Day' in Latin) that controls our body clock.

This body clock is adjusted to the local environment by external stimuli such as daylight, external light and eating a meal. All humans have their own body clock that keeps track of day and night and secretes hormones to prepare us for a good night sleep. 

Figure 1: circadian cycle (creative commons- Wikimedia)

circadian cycleCredit: cycle

When a normal person starts to wake up at around 7 – 7:30 melatonin secretion stops and cortisol production increases followed by a sharp increase in blood pressure (Fig 1). This is also the most dangerous time for a person to get a stroke; therefore eating a high carb meal is advised in the morning instead of a high fat meal.

At around noon most people start to feel a bit tired and hungry but this slowly fades away when approaching afternoon. At 17:00 most people enjoy the greatest cardiovascular efficiency and muscle strength, therefore it is advised to eat a high fat meal during this time. At 21:00 melatonin secretion starts and we prepare for the evening. It is time to relax and prepare our sleep.

When we fly to a different time zone our biological body clock has trouble adjusting and we can suffer from sleeping problems for up to a week.

Knowing how to reset this body clock is essential in getting a good sleep pattern and recover from a jetlag in as little as 1 day. Scientists are only now discovering the significant impact of eating a meal on our internal body clock. When people stayed up all night without eating they were able to recover and adjust their body clock very fast.

2. How can we Reset our Body clock to Fight a Jetlag?

It was previously thought that daylight had the biggest impact on our body clock but the timing when we eat meals is as equal important since fasting controls our sympathic nervous system.

airplaneCredit: airplane

Figure 2: Airplane (creative commons- Wikimedia)

In order to efficiently fight a jetlag a person can follow these simple tips to recover and reset the body clock:


  • Don’t eat during the time you are normally sleeping and wear sunglasses as much as possible. This will inform the body that its night by blocking external light.

  • When you arrive in a different time zone, break the fast and eat breakfast. This will active your symphatic nervous system and let your body know its morning.

  • When you prepare for a good night sleep take a melatonin supplement, this will trick your body in a sleeping state and adjust your body clock due to hormonal stimulation.


These three simple tips are useful to fight a jetlag, another problem people frequently face is a disturbed sleeping pattern. This disturbed sleeping pattern is often linked to a poor working body clock. If you have trouble falling asleep then try to stay up all night and only go back to bed the next evening. Also during the night, it’s important to not eat until breakfast next day.

Another very important tip in improving your sleeping pattern is to go to bed at the same time every single day, regardless of the situation. It’s also crucial to associate your bed with sleeping, so no texting or anything else in the bedroom but sleeping!

 To end this article I have a last tip to fine-tune your body clock for people who are in front of the computer a lot. There is a program called F.Lux that changes your desktops color so that the light of your screen influence your body clock.

That’s it, happy sleeping!