As many of you know I travel abroad 3 or 4 times a year, mostly to visit family or go to conferences. So many of us have gone global… there are 30 million travelers who fly from the US for destinations that are at least 5 or more time zones away from their home. Most suffer from jet lag upon arrival at their destination and then, alas, upon return. A recent review of jet lag appeared in the New England Journal of Medicine. I thought it appropriate (as I prepare to fly 7,000 miles in early April,) to share this pertinent information with you.
Jet lag is due to a temporary misalignment between your internal clock (termed the circadian clock) and local time. Your brain’s time and function follows a light-dark cycle set by the sun. And this internal clock does not readjust at the speed of jet travel. As a result, many travelers experience insomnia, daytime sleepiness, mood changes (I get grumpy) and fatigue. Fatigue may also be due to the fact that you are immobile, don’t eat right, become dehydrated and stressed with log-distant air travel. (And I am not even considering the stress that must have accompanied that recent “delayed flight” on Virgin Atlantic lasting 17 hours from LAX to JFK!)
There are a number of factors that contribute to jet lag:
- The number of time zones crossed: Obviously, the more the worse it gets, and if the trip is long, even if the number of crossed time zones are not great (i.e. the same latitude), travel fatigue can cause symptoms.
- Direction of travel: It is usually more difficult traveling east then west .Most people find it is easier to lengthen the day than to shorten it. (Unless like me you are a “morning type”, in which case the reverse can happen.) It’s estimated that the circadian clock resets an average of 92 minutes each day on a westward flight and 57 minutes earlier each day after an eastward flight.
- Sleep loss during travel: Chances are if you are in coach you will not be able to stretch out and go to sleep.
- Loss of light cues (exposure to natural light at your destination): If it’s the “wrong” time or if you arrive in non sunny weather, you don’t get the sun light that helps your brain adjust.
- Ability to tolerate circadian misalignment: Some people just can….hope it’s our politicians! Tolerance seems to decrease with age. Oi!
There are a few strategies that seem to somewhat mitigate jet lag:
- Optimize light exposure: Try to get bright sun light in the evening if traveling Westward, not the early morning and seek exposure to bright light in the morning if traveling Eastward (you get up much earlier so try to take a morning walk.)
- Take melatonin: Melatonin is the hormone that is secreted for about 10 to 12 hours at night and is a darkness signal. You can purchase melatonin without prescription. To promote shifting of the body clock to a later time when you travel westward take 0.5 mg during the second half of the night until you become adapted to local time. If you are traveling eastward take 0.5 to 3mgs at local bedtime nightly until becoming adapted.
- Schedule sleep changes ahead of time: Try to go to sleep 1-2 hours later than usual for a few days before your westbound trip and go to sleep 1-2 hours earlier for a few days before your trip east.
- Sleep medications. They help; you might try taking medications such as Ambien or Lunesta at bedtime for a few nights until you have adjusted to local time.
- Agents that promote alertness: Caffeine works, but avoid it after midday so it won’t adversely affect your sleep. Armodafi (Nuvigil)l and Modafinil (Provigil) which are drugs approved for narcolepsy and for shift workers (to improve alertness) have been show to reduce symptoms of jet lag if taken in the morning. They are not yet FDA approved for jet lag. Side effects include headache and nausea.
- On the plane: If possibly fly after you have had a good night’s sleep. Travel in business or first class (but know your health insurance won’t pay for this, even if your doctor recommends it). Drink lots of water, don’t consume caffeine if you expect to sleep on the flight, and don’t imbibe alcohol if you take a sleeping pill. You can try taking a short acting sleep medication such as Sonata. If the flight is more than 10 hours you can consider taking a longer acting sleeping pill such as Ambien or Lunesta. (Make sure the flight takes off and is OK before taking any of these.)
- Exercise when you are at your destination…it can have an impact on your circadian rhythms.
So here’s hoping you have a safe and uneventful trip and that a few of these tips will help you enjoy the first few days of your arrival and return. I will be off trying all these jet lag preventions during the first 2 weeks of April. I’ll be back in the office and seeing patients after the 15th. I intend to be alert!