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One of the challenges of executive life is the problem of frequent travel. While business class on airlines and comfortable hotels makes travel easier to endure, jet lag can be a serious problem with unexpected health consequences that no amount of creature comforts can lessen.
Numerous studies have shown that shift workers who have what is called circadian misalignment, basically long-term jet lag, suffer more heart attacks and cancers than people on normal sleep schedules.
Jet lag results when your circadian clock is out of sync with the schedule you are keeping. It is not just your brain – research has shown that other parts of your body, such as your digestive system, also have internal clocks and it is possible to suffer “gut lag” when you eat at the wrong time. Many people find it harder to travel eastward for several time zones than westward, because it is harder to go to sleep earlier than normal.
Charmane Eastman, a specialist in biological rhythms at Rush University Medical Center in Chicago, has been studying jet lag for years. She recommends slowly altering your sleep schedule before you get on a plane to ease jet lag at your destination. Dr Eastman says it is best to alter your schedule by about an hour a day when travelling eastward, and about an hour and a half when heading west.
When you travel from New York to London, as I did last week, you need to advance your body clock by five time zones. If I had been flying westward to Hawaii, I would have delayed my body clock. In order to reset your body clock, Dr Eastman recommends using a combination of light therapy and a hormone called melatonin, which can require a doctor’s prescription in some countries. Melatonin is produced in the pineal gland and its output is directly related to our sleep cycle. When bright light hits receptors in the eye, melatonin production comes to a halt, telling your brain to put your body clock on a daytime schedule. “In our studies in the lab, we used melatonin alone and light alone and both combined, and found that using both together works best [to change your body clock]. It’s additive,” she says.
I have also been using a small, portable light box made by Philips Electronics called the GoLite Blu, which costs about £200 ($200 in the US) and emits strong blue light. Philips says studies have shown that blue light has the most profound effect on the brain in shutting off melatonin production, ending your sleep cycle.
To adjust for this recent trip, I rose half an hour earlier each day and used the GoLite. Then, about seven hours before my new bedtime, I took a 3mg tablet of melatonin. For five days, I got up 30 minutes earlier each day and went to sleep an hour earlier. By the time I left for London, I was falling asleep at 8pm and getting up at 4am.
Thanks to this preparation, I experienced much less jet lag than I usually do. I normally cannot fall asleep until 1am or 2am in London because my body clock is still on New York time.
Had I been flying westward to China, where I have experienced extreme jet lag because of the 12-hour time difference, the trick would be to delay rather than advance. So I would use the light box before bed at night in order to become sleepy progressively later each night and take melatonin in the morning. Dr Eastman says it may be better to take a smaller dose of melatonin such as 0.5mg in the mornings so that you do not experience sleepiness in the daytime.
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