How Our Sleep Rhythms Are Controlled
Jet lag happens when travel across time zones disrupts our internal body clock, or circadian rhythm and is considered a sleep disorder.
A key factor in how our sleep is regulated is exposure to light or to darkness. Exposure to light stimulates a nerve pathway from the retina in the eye to an area in the brain called the hypothalamus. There, a special centre called the suprachiasmatic nucleus (SCN) initiates signals to other parts of the brain that that are involved in making us feel sleepy or wide awake.
Once exposed to the first light each day, the clock in the SCN begins performing functions to prepare us for the day ahead, including raising body temperature and releasing stimulating hormones like cortisol. The SCN also delays the release of other hormones like melatonin, which helps us feel sleepy, until many hours later when darkness arrives.
Melatonin is a natural hormone made by your body’s pineal gland. This is a pea-sized gland located just above the middle of the brain. During the day the pineal is inactive. When the sun goes down and darkness occurs, the pineal is “turned on” by the SCN and begins to actively produce melatonin, which is released into the blood. Usually, this occurs around 9 pm. As a result, melatonin levels in the blood rise sharply and you begin to feel less alert. Sleep becomes more inviting. Melatonin levels in the blood stay elevated for about 12 hours – all through the night – before the light of a new day when they fall back to low daytime levels by about 9 am. Daytime levels of melatonin are barely detectable.
How Air Travel Affects Your Body and Mind
Jet lag can result in mental, emotional and physical symptoms such as:
|Pressure in the ears due to changes in air pressure. Chewing gum during ascent, and swallowing or yawning during descent can help equalise the pressure|
|Headache due to low oxygen. Prevent by drinking plenty of water and avoiding caffeine and alcohol during the flight|
|Foot, ankle and leg swelling, raising your risk for a blood clot, due to impaired blood flow. Prevent by standing up now and then, and flexing, rotating and extending your ankles while sitting. Compression stockings may also be helpful|
|Dehydration due to dry air. Prevent by drinking plenty of water before and during the flight|
|Toothache due to shifts in air pressure. There’s no way to prevent the pain associated with the expansion of gas trapped in fillings or cavities, so see a dentist before traveling if you suspect you have a problem|
|Fatigue, sleepiness, increased reaction times and reduced ability to make decisions due to low oxygen|
|Gassiness due to shifts in cabin pressure|
|Altered/dulled sense of taste and smell. Taste sensitivity can be restored by staying well hydrated|
|Dry skin due to dry air — a problem easily addressed with moisturizing lotion. Also, be sure to drink plenty of water|
|Bad breath due to dry mouth. Remedy by brushing your teeth on the plane and staying well hydrated|
How to Reduce Symptoms of Jet Lag
When you’re traveling shorter distances
If your destination is just one or two time zones away, it may be possible to wake up, eat, and sleep on your regular home schedule. At your destination, schedule appointments and activities for times when you would be alert at home.
When you’re traveling longer distances
As a general rule, your body will adjust to the time zone change at a rate of one time zone per day. What this means is, if you need to be at your physical or psychological best, you’d want to fly out one or more days ahead of time. If you cannot squeeze in the extra time, you could act “as if,” and pretend you’re in your destination time zone while still at home.
To do this, gradually switch your routine before the trip. For several days before you leave, move mealtimes and bedtime incrementally closer to the schedule of your destination. Even a partial switch may help. As an example, if you were planning to travel from New York to Paris, start going to bed (and shift your mealtimes up) an hour earlier each day, three days ahead of your flight, and avoid bright light for two to three hours before going to bed.
During the flight
- Drink plenty of fluids, but not caffeine or alcohol. Caffeine and alcohol promote dehydration, which worsens the symptoms of jet lag. They can also disturb sleep.
- If traveling at night, wear blue-blocking glasses on the plane, and continue wearing them until you go to sleep, as excess blue light will impair your melatonin production and make it difficult to fall asleep
- Jet lag checker : https://www.britishairways.com/travel/drsleep/public/en_gb Dr Idzikowski , director of The Edinburgh Sleep Centre, has drawn up a jet lag checker for passengers, which tailors the amount of time and when passengers are to wear sunglasses. Dr Idzikowskisaid that without using sunglasses it took a day to recover for every hour of time difference travelled westwards.
Once you’re at your destination
- Switch your bedtime as rapidly as possible upon arrival. Don’t turn in until it’s bedtime in the new time zone.
- If you have travelled east, try going to sleep earlier and getting up and out into the early morning sun. Or if not possible switch on the lights, to shut down melatonin production (the hormone which makes you feel sleepy)
- If you travelled west, try to get at least an hour’s worth of sunlight as soon as possible after reaching your destination
- The sunlight will cue your hypothalamus to reduce the production of sleep-inducing melatonin during the day, thereby initiating the process of resetting your internal clock
- The sooner you adapt to the local schedule, the quicker your body will adjust. Therefore, if you arrive at noon local time (but 6 a.m. your time), eat lunch, not breakfast.
Avoid Alcohol and Caffeine Consumption Before Bed
Both alcohol and caffeine can adversely affect quality of sleep when they’re consumed a few hours before bedtime. Alcohol should be avoided altogether if you still have jet lag and caffeine should only be consumed in order to enhance daytime alertness.
Studies show that when caffeine is consumed too close to bedtime, it may result in difficulty falling or maintaining sleep. This can lead to exposure to light during the night, which further shifts the internal clock out of phase with the new light-dark cycle.
The Anti-Jet Lag Fast
Devised by a team of researchers at Harvard and Beth Israel Deaconess Medical Centre in Boston, the anti-jet lag fast involves determining the time of breakfast at your destination and then fasting (abstaining from all food and drink except noncaloric beverages like water) for 12 to 16 hours beforehand. One of the researchers states “Since most of us go 12 to 16 hours between dinner and breakfast anyway, the abstention is a small hardship.”
This strategy is thought to work because fasting causes your master clock to suspend the circadian clock and instructs your body to sleep less. When food intake resumes, the master clock switches the circadian clock back “on.”
“The master clock probably evolved because when our prehistoric forebears were starving, they would have been tempted in their weakness to sleep rather than forage for the food they needed to survive.
Today, when a traveller suspends his circadian clock before flying from Los Angeles to London, and then reactivates it upon breaking the fast, the clock doesn’t know that it should still be on Pacific Time. It knows only that the breakfast and the daylight declare morning in Mayfair, and it resets the body’s rhythms accordingly.”
Minimize Jet Lag With Traditional Chinese Medicine
You can also trick your body into connecting with a new time zone using Traditional Chinese Medicine techniques involving the stimulation of certain acupuncture meridians.
Borrowing the knowledge of the general circulation of chi, and being aware that each meridian undergoes a two-hour time peak that moves and peaks from meridian to meridian as it travels through its general circulation, it was reasoned that if one were to reset the body clock utilizing the horary cycle, the body in theory could be made to function at the horary cycle of wherever the person is physically located on the planet, disregarding the effects of so-called ‘time travel.’
Cardiologist Dr. Lee Cowden devised a shorter version of this technique, focusing on just one meridian — the heart meridian. He explains this technique in the very short video below, originally taped in 2009. Here’s a summary of the steps:
- The day of your trip, set your clock to match the local time at your destination (depending on the time of your flight, you may have to do this a day ahead)
- At 11 a.m. (the local time at your destination), stroke your heart meridian three times on the left and three times on the right. Your heart meridian begins just to the outer side of your nipple, up through your armpit and down the ulnar aspect (inner side) of your arm, down the outside of your pinky. Once you reach the end of your pinky, gently press into the base of the fingernail (heart point in Traditional Chinese Medicine). For a demonstration, please see the video below.
- At noon, repeat the heart meridian strokes
Watch the video here: https://www.youtube.com/watch?time_continue=7&v=K3qlO3wM8ho