Any travel lover will know the frustration of arriving somewhere new and exciting and wanting to explore, before being hit with debilitating jet lag.
Fortunately, US scientists think they finally have a solution, saying it’s all about what and when you eat.
They say that eating a single large meal early in the morning for three days after landing can kill jetlag, though the older you get, the less likely it is to work.
Experts agree that taking a walk in the sun is another good tip, so combining it with the new advice puts travelers on the best path to recovery.
It is well known that one of the worst things you can do when faced with jetlag is to refuse to assimilate to your new time zone, such as going to sleep during the day.
Jet lag is caused by a difference between the circadian system (the body’s internal clock) and the environment.
The new study was conducted by experts from Northwestern University in Evanston, Illinois, and the Santa Fe Institute in New Mexico.
“Eating more first thing in the morning in the new time zone can help overcome jet lag,” said study author Yitong Huang, of Northwestern University.
“Constantly changing meal times or eating at night is discouraged, as it can lead to misalignment of internal clocks.”
Jetlag is caused by disruptions in humans’ innate biological clock, called the circadian rhythm, which regulates when we’re sleepy and when we’re most alert.
Modern research has shown that circadian clocks are present in almost all cells and tissues in the human body and can vary from organ to organ.
For example, the brain’s main clock is a group of about 20,000 nerve cells that form a structure called the suprachiasmatic nucleus (SCN), which receives input directly from the eyes.
The brain’s clock can be reset by exposure to sunlight, so jetlag sufferers are advised to soak up the daylight in their new location rather than succumb to sleep.
Specifically, sunlight affects the production of a hormone called melatonin (produced by the pineal gland in the brain) that helps regulate sleep.
When we are exposed to sunlight, melatonin production is suppressed, which helps us stay awake during the day.

When the eyes receive sunlight, the production of melatonin by the pineal gland is inhibited and the hormones produced keep us awake. When the eyes do not receive light, melatonin is produced in the pineal gland and the human gets tired
Meanwhile, peripheral organs like the stomach and liver have their own separate clocks that are recalibrated by food: that is, what and when we eat.
Jet lag can occur when these clocks are out of sync with each other, the research team says.
“Contradictory signals, such as hot weather during a short daylight period or eating at night (eating when the brain is about to rest) can confuse internal clocks and cause desynchrony,” Huang said.
For the study, the authors used software to study the interactions between multiple internal clocks with jetlag and how this is affected by aging.
They built a model consisting of two “oscillators” stacked on top of each other: one represents the clock controlled by sunlight and the other the clock controlled by food.
Using this model, the team was able to explore how such a coupled system could be disrupted, and what makes the effect worse.
The results suggested that the best option is to have one meal per day early in the morning for the first three days, but containing three times the volume of food.
However, aging results in weaker signals between circadian clocks and decreased sensitivity to light, they also found.

The illustration shows the mathematical model of the equipment. It consists of two populations of coupled oscillators, where one population represents the central brain clock, influenced by light, and the other population represents a peripheral clock, influenced by food.
This means that older people who experience jet lag after a long flight may need more days to recover compared to younger people.
The authors plan to investigate the other side of the equation and identify the factors that result in stronger internal clocks.
Such discoveries could lead to recommendations to prevent jet lag in the first place, or to keep the circadian system healthy well into old age.
The team admits that little is known about how the body’s various internal clocks affect each other, although they refer to the brain as the “central clock” because it coordinates all other clocks.
“Experimental data clearly demonstrate a hierarchical network of clocks in mammalian animals and these clocks respond to different external stimuli,” they state in their article, published in the journal Chaos.
“Therefore, a mathematical framework containing both the central clock and peripheral clocks is necessary to advance our knowledge of circadian rhythms.”