Most people who routinely fly have experienced at one time or another the nagging impacts of jet lag. The all-too`-familiar symptoms include insomnia, sleepiness, moodiness and gastrointestinal disorders – impacts that can often disrupt a business trip or vacation. In the Feb. 4 edition of the New England Journal of Medicine, Oregon Health & Science University physician-scientist and nationally recognized sleep researcher Robert Sack, M.D, was invited to provide expert advice on preventing or diminishing the effects of jet lag.
"Jet lag affects a large proportion of the more than 30 million travelers who embark from the United States each year and cross five or more time zones," said Sack. "The condition is specifically caused by crossing time zones at a speed more rapid than the body's circadian clock can keep pace. As a result, the body clock and local time become misaligned for a period that can last up to a week or more. Treatments for jet lag are specifically geared toward speeding up the realignment of the circadian clock and local time."
Sack's article provides specific steps aimed at counteracting jet lag, including:
- The use of light exposure - Following a plane flight, exposure to or avoidance of bright light during certain periods of the day can more rapidly shift one's circadian clock. Specifically, Sack suggests seeking bright light exposure in the morning after eastward travel, and in the evening after westward travel. Avoiding light at times of the day when it would inhibit resetting of the body clock can also be important.
- Melatonin - Another proven therapy is the supplement melatonin, a hormone which is normally secreted by the pineal gland at night. "When melatonin is taken in the evening, it resets the body clock to an earlier time," said Sack. "Conversely, when it is taken in the morning, it resets the clock to a later time. Of course, before taking melatonin or any other supplement, you should first consult your doctor."
- Sleep scheduling - Research has also shown that a simple way to minimize jet lag is to begin shifting one's sleep schedule towards the destination time zone prior to a trip. For instance, one might go to bed several hours earlier for a few days prior to an eastbound trip. In addition, short daytime naps in the days following arrival can also be helpful.
- Caffeine - "It's of course no surprise that caffeine can counteract daytime sleepiness tied to jet lag. The risk of course, is the exacerbation of insomnia at night, another common jet lag problem," said Sack. "There are also medications that promote wakefulness. However, some of these agents can also cause headaches and other unwanted side effects. In other words, we need to look further into this area before providing further advice."
In summary, Sack suggests that when possible, travelers should combine several of these approaches: shifting sleep patterns prior to departure, seeking or avoiding sun exposure to accelerate one's body clock at a faster rate and the use of melatonin, provided a person's physician approves.
Robert Sack, M.D., a professor of psychiatry in the OHSU School of Medicine is medical director of the OHSU Clinical Sleep Disorders Medicine Program.
Oregon Health & Science University is the state's only health and research university and Oregon's only academic health center. OHSU is Portland's largest employer and the fourth largest in Oregon (excluding government). OHSU's size contributes to its ability to provide many services and community support activities not found anywhere else in the state. It serves patients from every corner of the state, and is a conduit for learning for more than 3,400 students and trainees. OHSU is the source of more than 200 community outreach programs that bring health and education services to every county in the state.