The body has an internal clock of sorts that follows the rhythms of night and day. Airplane travel confuses this clock, causing the phenomenon known as jet lag. If you’ve ever crossed several time zones, you’ve probably experienced jet lag to some degree. You may have felt exhausted in the morning and wide awake at night, and between those times experienced symptoms such as fatigue, loss of concentration, dizziness, lightheadedness, irritability, nausea, and headache.
Ordinarily, the body clock resets itself within a few days. It is possible to speed up this natural process by deliberately using stimuli to indicate to your body when you want it to wake up and when it should fall asleep. Common methods involve social activity and outdoor exercise during the daylight, combined with meal times appropriate to the new time zone. It is also generally considered important to stay awake upon arrival in the new time zone until night falls. Use of sleeping pills may be helpful at first, so you don’t stay awake staring at the walls. In addition, some physicians are experimenting with wakefulness drugs used for narcolepsy, such as modafinil, to help travelers stay active and alert on arrival.
Melatonin is a natural hormone that plays a role in the day-night cycle (the circadian rhythm). During daylight, the pineal gland in the brain produces an important neurotransmitter called serotonin. But at night, the pineal gland stops producing serotonin and instead makes melatonin. This melatonin release helps trigger sleep.
The amount of melatonin production varies according to the intensity of light to which you're exposed; for example, your body produces more melatonin in a completely dark room than in a dimly lit one.
This cyclic pattern of melatonin release helps set the body’s biologic clock. Melatonin supplements taken by mouth can be used to reset this clock, an effect of potential benefit in jet lag.
According to a review published in 2001, reasonably good evidence indicates that melatonin is indeed effective for this purpose.1 One of the best supporting studies was a double-blind, placebo-controlled study that enrolled 320 travelers crossing six to eight time zones.2 The participants were divided into four groups and given a daily dose of 5 mg of standard melatonin, 5 mg of slow-release melatonin, 0.5 mg of standard melatonin, or placebo. The results of this large study were promising. The group that received 5 mg of standard melatonin slept better, took less time to fall asleep, and felt more energetic and awake during the day than the other three groups.
For more information, including dosage and safety issues, see the full melatonin article.
NADH is a chemical that the body manufactures on its own to serve a variety of biologic purposes. In a double-blind, placebo-controlled trial, 35 people taking an overnight flight across four time zones were given either 20 mg of NADH or placebo sublingually (under the tongue) on the morning of arrival.3 Participants were twice given tests of wakefulness and mental function: first at 90 minutes and then at 5 hours after landing. People given NADH scored significantly better on these tests than those given placebo.
Tyrosine is an amino acid found in meat proteins. A double-blind, placebo-controlled study that enrolled 20 U.S. Marines suggests that tyrosine supplements can improve alertness during periods of sleep deprivation.4 In this study, the participants were deprived of sleep for a night and then tested frequently for their alertness throughout the following day as they worked. Compared to placebo, 10 to 15 g of tyrosine given twice daily seemed to provide a "pick-up" for about 2 hours.
Similar benefits were seen with 2 g of tyrosine daily in a double-blind, placebo-controlled trial of 21 military cadets exposed to physical and psychological stress, including sleep deprivation.5 These finding suggest that tyrosine could be helfpul for jet lag.
Besides these supplements, all the natural treatments used for insomnia may be helpful for getting a good night’s sleep on the first night of travel. See the full insomnia article for more information.
1. Herxheimer A, Petrie KJ. Melatonin for preventing and treating jet lag. Cochrane Database Syst Rev. 2001;(1):CD001520.
2. Suhner A, Schlagenhauf P, Johnson R, et al. Comparative study to determine the optimal melatonin dosage form for the alleviation of jet lag. Chronobiol Int. 1998;15:655–666.
3. Kay GG, Viirre E, Clark J. Stabilized NADH as a countermeasure for jet lag. Presented at: 48th International Congress of Aviation and Space Medicine; September 17–21, 2000; Rio de Janeiro, Brazil.
4. Neri DF, Wiegmann D, Stanny RR, et al. The effects of tyrosine on cognitive performance during extended wakefulness. Aviat Space Environ Med. 1995;66:313–319.
5. Deijen JB, Wientjes CJ, Vullinghs HF, et al. Tyrosine improves cognitive performance and reduces blood pressure in cadets after one week of a combat training course. Brain Res Bull. 1999;48:203–209.
Last reviewed December 2015 by EBSCO CAM Review Board
Last Updated: 12/15/2015