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Biologist Charles Ehret Says Jet Lag Is Avoidable Even on a Fast Plane to China

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As every high-flying traveler knows, jet lag is the curse of time-zone spannings at sonic speeds. Even airline veterans often end their long journeys feeling as though they had walked the distance. The symptoms include exhaustion, confusion and an irresistible urge to spend the first day of a vacation or business trip sleeping it off.

Yet on Ronald Reagan’s arrival for a scheduled five-day state visit to China this week, he should appear as fresh as he was when he boarded Air Force One in Washington. His beaming entry to Peking after the grueling flight will not be attributable entirely to the needs of protocol or to the remarkable resiliency of the septuagenarian President. He will also be able to thank a special anti-jet-lag regimen devised by Dr. Charles F. Ehret, 61, biologist and senior scientist at the Argonne (Ill.) National Laboratory. The idea is to keep the President’s “body clock” ticking in sync with Chinese local time through the official ceremonies (including the obligatory trek along the Great Wall) and, more important, during the summit-level negotiations. At such critical times, Ehret notes, “no diplomat wants to fall asleep or make a mistake in judgment. He has to be alert.”

Happily the President’s anti-jet-lag plan is no state secret but is available to anyone. It’s all spelled out in Ehret’s book, Overcoming Jet Lag (written with Lynne Waller Scanlon, Berkley, $4.95), which is now in its third printing. In essence it is a diet program in which days of feasting are alternated with days of fasting to move the body clock forward (if the destination is eastward) or backward (if headed westward).

Jet lag is apparently caused by the disruption of body rhythms. Everyone’s physical functions are timed to about a 24-hour cycle that regulates sleeping, waking and body temperature, and traveling to a different time zone causes a jarring disruption of these circadian rhythms. “You are a different person biochemically at 6 in the morning than you are in the evening,” Ehret explains. “It’s like being a redhead at dawn and a blond at midnight.”

Ehret’s system is designed to fool the biological clock into jumping ahead or backward. How and when you start the diet depends on where you are going and how many time zones you are crossing. Let’s suppose you will be flying from New York to Italy on a Rome vacation this summer. You should begin the diet three days before your flight. Try to give up all liquor and wine for the duration of the diet, and drink coffee, tea, colas and other caffeinated beverages only between 3 and 5 p.m. If taken in the morning or evening, caffeine disrupts the body clock.

The first day of your program is a feast day, and you can have all the ham, steak and eggs you want for breakfast and lunch. But in order to encourage sleep, supper must be low in protein and high in carbohydrates, such as pasta, bread and desserts.

Day Two is a fast day. You should still have a light, high-protein breakfast and lunch and a light dinner, but you should consume no more than 800 calories. A typical fast menu would be eggs and cottage cheese for breakfast, tuna for lunch, and salad and fruit for dinner. The lowered carbohydrate intake uses up the liver’s supply of glycogen (a muscle fuel) to prepare the body clock for resetting, as Ehret says, “like a spring-driven watch.”

Day Three—the day before the flight—is another feast day with a high-protein breakfast and lunch and a high-carbohydrate supper.

Flying day starts out as a fast day. Eat a low-calorie, high-protein breakfast and lunch, but then a high-carbohydrate supper. Between 7 and 11 p.m., no matter where you are, drink two to three cups of black coffee or strong, plain tea. If yours is a night flight, everyone in Rome will be asleep even as you are boarding the plane, so you should start doing as the Romans do and try to sleep too. That could be difficult because of all the caffeine in your system. “The important thing is to relax,” advises Ehret. “When you close your eyes and stop socializing, your body chemistry achieves a state of rest. Don’t watch the movie, don’t read and don’t talk.” Above all, avoid alcohol. Although it may help you sleep, drinking will only upset your body rhythms.

If you are still en route when it’s breakfast time in Rome, get up anyway, wash your face and brush your teeth. The most important aspect of this phase is to eat a high-protein breakfast because, Ehret says, it signals “your central nervous system that a new time frame has begun.” You can then play solitaire, search the skies for UFOs or do anything, just stay awake. If you fall asleep, you’ll slip back into your old time schedule, and the plan is ruined. But assuming you don’t backslide, your body should be on Rome time, and you should arrive in Italy bright-eyed and lively while everyone else gropes off the plane.

Sounds good, but does it work? Many frequent travelers say yes. Last August the Minnesota Vikings played a first-time-ever exhibition game of American pro football in London, and many of the team members followed the anti-jet-lag diet. Their opponents, the St. Louis Cardinals, did not. Final score: Vikes 28, Cards 10. The diet is also used by the Army’s elite 82nd Airborne Division as part of an overall program to reduce the effects of jet lag in rapid deployment forces. And Control Data Corp. has adopted it for its globe-trotting executives. Mary Foley, a consultant in the company’s StayWell program, says execs who’ve followed Ehret’s regimen “are not burned out with jet lag and can make decisions. They don’t have to lose a whole day.”

As a boy in the Bronx, Ehret’s main interests were bird watching and trout fishing. He decided to become a biologist while recuperating from a heel wound received as an infantry man with Patton’s Third Army in Europe during World War II. After graduating from City College of New York in 1946, he received his Ph.D. in biology from Notre Dame and then joined Argonne. There he studied microscopic paramecia and discovered that even these simple, one-celled critters have a circadian clock that causes them to mate in the light of day but not at night. Ehret fooled them by artificially altering the light-dark cycle in the lab, for which a colleague jocularly dubbed him “the Kinsey of the protozoa.”

In 1975 Ehret’s circadian experiments became more personal when he, his wife, Dorothy, and two of their six children flew to Vienna for a convention. Through his system the family made the round-trip between Austria and Hinsdale, III. “feeling terrific” when “everyone else on the airplane was zonked out,” Ehret recalls in triumph. Word of his discovery circulated, and he put it in book form last year.

Ronald Reagan first followed the anti-jet-lag diet on his visit to Korea and Japan last November, and “it helped a lot,” says Dr. Daniel Ruge, the President’s personal physician. But even Ehret concedes that there are caveats: How effective the anti-jet-lag diet proves to be depends on how closely it is followed. If you don’t—or can’t—drink beverages containing caffeine, or if you must drink liquor, “the diet may not work as well,” he cautions. Of course, if you were to get on a slow boat to China or somewhere, you wouldn’t have to worry about any of this at all.