How to Beat Jet Lag

Whether you’re crossing time zones or working shift work, circadian rhythm disruption takes a toll, and is worse for women. Here’s what to know.

Anyone who’s been in an airport lately knows that travel is back. Airports and planes are packed as people take long overdue vacations, head to destination races, conduct business face to face, and make trips to reconnect with family and friends. That means you may be experiencing something else you haven’t felt for a long time—jet lag.

Jet lag is a temporary disruption of your normal circadian rhythm caused by high speed travel across several time zones. Typically, your circadian rhythms align with daytime and nighttime where you live, so your core body temperature, hormone production, and melatonin levels rise and fall to help you be alert come morning and during the day and sleep at night. When you travel out of your time zone, especially across three or more time zones, you experience jet lag: your body’s internal clock becomes out of sync with the local time of your destination. 

This leaves you feeling disoriented and fatigued and can disrupt your sleep patterns, which can make the fatigue worse. It can also throw off digestion, leaving you constipated, queasy, and without your normal appetite.

Women who work shift work can experience the same phenomenon without ever stepping foot on a plane. In fact, the circadian rhythm disruption and sleep-wake disorders caused by working odd hours is sometimes called “social jet lag”.

Jet Lag is Worse for Women

Jet lag affects everyone, but this time-lag can take a bigger toll on women, because our circadian rhythm influences the release of hormones like estrogen and progesterone, which impact our menstrual cycle, appetite hormones and blood glucose control. Disturbing your circadian rhythm can disrupt the release of these hormones, leading to a change in your period. Research finds that female flight attendants who work routes that leave them with chronic jet lag have fertility issues, as well as a higher risk for breast cancer.

Research on shift workers shows that the circadian misalignment caused by working odd hours may predispose you to weight gain by decreasing your total energy expenditure and altering your food intake. Here, too, females are affected differently than males. We experience more disturbances in the energy homeostasis process, meaning that our bodies struggle more to maintain energy balance. Research shows we have a 7 percent decrease in our satiety hormone leptin (while males have an 11 percent increase) and an 8 percent increase in the hunger hormone ghrelin (males have no significant change). 

How to Manage Circadian Rhythm Disruption

Whether you’re flying to Kona or working the night shift, you can take steps to shift your internal clock and feel and perform better. Here’s how to take the sting out of physical and social jet lag.

When Flying…

• Adjust your sleep/wake times. You can help mitigate jet lag by adjusting your sleep/wake times ahead of your travel.
• Traveling west to east: Jet lag tends to be a little more pronounced when you fly west to east. In the four days before your trip, drink 4 ounces of tart cherry juice (for natural melatonin) with 400 milligrams of valerian about 30 minutes before bed. Go to bed and wake up 1 hour earlier than usual. Expose yourself to bright light, preferably sunlight, which has a powerful effect on your circadian rhythms, as soon as possible after waking. When you arrive, try to avoid bright light exposure. Wear sunglasses if the sun has not set, and seek dimly lit environments to signal your body that it is time to wind down and sleep.
• Traveling east to west: It’s easier to adjust your circadian rhythm flying west because your body adjusts more easily to a longer day. If your work schedule allows, make the adjustment easier by pushing back your bedtime and wake time by about 30 minutes for the two to four nights before your flight. Expose yourself to bright light, preferably sunlight, which has a powerful effect on your circadian rhythms, as soon as possible after waking. When you arrive, help your body reset to the later start of the day by exposing yourself to bright light (sunlight preferably), and do not wear sunglasses the first few days in the new location, all to help your internal clock make the shift.
• Limit caffeine. On your travel day, limit your caffeine intake to your normal morning hours (between 6 a.m. and 11 a.m.) of your home time zone.
• Avoid alcohol. You don’t want anything that will further disrupt your sleep architecture, and alcohol definitely does. Plus, it dehydrates you, which is the last thing you need during air travel, which is already dehydrating.
• Get outdoors. If you land during the day, go for a walk outside without sunglasses to use sunlight to reset your body clock. This will help you adjust to your new time zone.
• Stay hydrated. Before, during, and after your flight take regular sips of a low-carbohydrate, electrolyte drink (it can be as simple as a sprinkle of salt and a teaspoon of sugar in 16 ounces of water) to stay hydrated, which will also help with digestion as you travel.
• Snack lightly. Nibble on some fresh fruit, high-fiber crackers, or trail mix to keep your GI tract moving along as you travel.

For Shift Work…

Much of the same advice applies in that your goal is to use light, caffeine, and melatonin manipulation to minimize your sleep debt, keep your biological processes like hunger and digestion in sync, and improve performance. We know from sleep deprivation research that women tend to crave more carbohydrates, which can wreak havoc on blood glucose control. Thus eating a protein-centric meal upon waking can help minimize the disruption to the glucose-insulin balance.

The BMJ published a great infographic on optimizing sleep for night shifts here. Some of the key tips include:

• Pushing off morning awakeness on day 1: Sleep in and avoid morning caffeine the day you start your night shift. If possible, take a nap in the afternoon.
• Maintaining awakeness and alertness during a night shift: Stay as active as possible, snack lightly, stay hydrated, and limit caffeine to the first half of the shift, preferably having your coffee right before a nap break. On the way home, wear dark sunglasses and avoid bright light exposure.
• Recovering between shifts. Sleep as early as possible after your shift in a quiet, cool, dark room.
• Re-establishing sleep patterns after a night shift. Take a nap as soon as possible after the last shift. Go outside and expose yourself to bright daylight and get some exercise after waking up. Go to bed at your normal time.