sleep better

Clock out of rhythm

The biological or circadian clock plays an essential role for our preferred sleeping time, for the phase of our highest attention and for other physiological processes. The biological timer switches genes on and off at the right time, thus allowing the organism to adapt to the rotation of the earth. If the synchronisation between the physiological rhythm of our body and the rhythms of the environment is disturbed permanently or repeatedly, this not only reduces our performance, but also increases the risk of various diseases, such as diabetes, cardiovascular diseases, sleep disorders and cancer.[1]

If we suffer from jet lag, then our circadian rhythm is upset – our biological inner clock, which controls our sleep-wake rhythm. When we cross several time zones, our inner clock is no longer synchronized with the reality around us. Then our body needs some time to adjust to the rhythm of the new time zone.

The importance of the direction of travel

Jet lag is usually longer and more intense the more time zones you cross. For example, if you fly from Berlin to San Francisco for 14 days, the jet lag can last four to five days – this number corresponds to about half of the time zones crossed. If you fly from San Francisco back to Berlin, it can even take up to nine days to fully recover. Travelling east is generally more difficult for most people to digest, as they have to shorten their day-night rhythm. This is much more difficult for many people than prolonging it, as is the case with journeys to the west.

Escape from jet lag through nutrition

Whether long distance travel or simple shift work: the struggle with fatigue not only confuses people in their minds. The microbiome suffers too. The researchers led by Christoph Thaiss from the Weizmann Institute of Science first investigated in mice whether the composition of their intestinal flora changes within a 24-hour rhythm. And indeed: in the course of a day, the frequency of different types of bacteria increased and decreased again and again. The scientists then showed that the human intestinal flora is also subject to rhythmic fluctuations – and that jet lag also changes the composition of the bacteria.[2]

However, the right diet can reduce jet lag. For example, dinner should be enriched with ingredients that promote the release of insulin. This could turn the biological clock back a little towards morning. The exact opposite is then true for breakfast.[3]  In addition, a Harvard study found that fasting can also help to cope more quickly with the new local time.[4]

The research results therefore indicate that our diet can influence our biological clock.

• – Whoever fasts 12 to 16 hours before arrival time and takes only water, resets his or her internal clock to zero – this makes a new start on site easier.
• – If you land before 10 a.m. local time, you should have a light, protein-rich breakfast as soon as possible. If you land in the afternoon, a carbohydrate-rich meal around 4 pm is recommended. Continue with breakfast the next morning around 8 o’clock.
• – Those who appreciate coffee as a stimulant can increase its effectiveness by abstaining from it for a few days before the trip. If you then take coffee as a pick-me-up in small portions, the stimulating effect lasts longer, instead of fizzling out all the more quickly with a mega dose after an explosive high.

How can we use these findings to develop specialized foods that help us overcome jet lag as quickly as possible?

[1] Miho Sato, The Role of the Endocrine System in Feeding-Induced Tissue-Specific Circadian Entrainment. Cell Reports, 2014

[2] Christoph A. Thaiss et al., Transkingdom Control of Microbiota Diurnal Oscillations Promotes Metabolic Homeostasis, Cell 159, 514–529, October 23, 2014

[3] Miho Sato, The Role of the Endocrine System in Feeding-Induced Tissue-Specific Circadian Entrainment. Cell Reports, 2014

[4] Patrick M. Fuller et al., Differential Rescue of Light- and Food-Entrainable Circadian Rhythms, Science, 23 May 2008