A sugar rush could be all you need to beat jet lag. Now here’s scientific evidence that donuts and other insulin-spiking foods have some use other than making you overweight and at risk of diabetes.
Eating insulin-promoting foods helps to reset the body’s internal clock to help you get over jet lag faster, reported research published this week in Cell Reports. This means sugary food could be the evasive antidote to jet lag that leaves several thousands of travellers across time zones dull-witted, sluggish, grumpy and very, very exhausted.
Jet lag occurs when the travel across time zone upsets the body’s internal biological clock called circadian rhythm. This non-ticking clock regulates the body’s sleep-wake cycle, temperature and hormone function over a roughly 24-hour period. Most vitally, it controls the secretion of the sleep hormone melatonin, which typically starts at night, with the deepest sleep coming at about 2 am. Melatonin secretion stops at 7.30 am, when it is time for you to face the day and take on the world.
The circadian rhythm is regulated by light and is controlled by a small part of the brain called the suprachiasmatic nucleus, which lies above the optic nerves. Its job is to set the body clock by the light that falls on the eye’s retina and relay the information to the rest of the body through nerve impulses and hormones, the levels of which rise and fall match the 24-hour cycle.
For the new study, scientists at The Research Institute for Time Studies at Yamaguchi University in Japan did experiments in mice to show that apart from the brain, circadian rhythms are also present in peripheral clocks in different cell types in the body, many of which are influenced by food.
The Japan study demonstrated the role of insulin in its regulation. Scientists first shifted the peripheral body clock in the livers of mice by feeding them only at night, then split the mice into two groups, suppressed insulin levels in one group, and then returned all of them to daytime feeding.
Four days later, the livers of the mice with non- suppressed insulin had readjusted to a normal rhythm, but those of the insulin-suppressed mice had not.
The scientists concluded that jet-lagged people could similarly adjust their eating patterns to trigger insulin release to get their internal clocks to adapt to the rapid change in the light-dark cycle that accompanies travel across time zones.
Eating the in-flight dinner roll, then, appears to be a better option than the more popular one of knocking yourself out with alcohol. Alcohol helps you nod off quickly but that it interrupts later stages of sleep, which exacerbates jet lag.
Hangovers, most of us know from unforgettable experience, do not help you sleep any better even the next day. What does aid sleep is drinking water. Much like its effect on a hangover, dehydration intensifies the effects of jet lag, so drink as much as you can without being forced to make suspiciously numerous trips to the toilet.
Apart from sleep, the body clock also regulates body temperature and hormone function to prepare you for tasks ahead. It controls immune function, cell division, body temperature and digestion, so large and spicy meals are best avoided to not further wreck the sluggish digestion.
Much like shift workers, frequent flyers can suffer from chronic desynchronisation between their natural body clock and the frequently-changing time zones the find themselves in. Over time, this desync can hurt you more ways than just making you disoriented. It can contribute to a clutch of disorders such as diabetes, heart disease, sleep disorders, and some cancers.
Trying to get as much sleep as you can during travel helps you to stay up until night time on arrive at the destination. It’s easier said than done, as navigating immigration queues and security checks spike levels of the stress hormone cortisol, which is increases alertness, but try using eye masks and earplugs to get as much sleep as possible.
A minimum of four hours’ of sleep at night – known as “anchor sleep” – at your destination is needed to adapt to the new time zone. If possible, make up the total sleep time by napping during the day.
Avoid taking sleeping pills as they do nothing to help the body adjust naturally to the new sleeping pattern. Worse, if taken with alcohol, anti-allergy medicines or sedatives, they may knock you out for longer than needed. Synthetic melatonin works for some, but doctors prescribe it with caution as it is still unregulated in many countries.
Your safest bet, then, is to munch on donut and become a master of time-zone travel.