I have been traveling more than ever the past couple months and it seems that everywhere I go changes time zones.  I happen to be fairly lucky in the department of falling asleep and adjusting quickly; however, there are natural tricks that you can use to your advantage if you suffer from time changes.  Try to stay away from habit-forming pharmaceuticals that artificially alter your sleep-wake patterns because they end up doing you more harm than good long term.

1. Eat on schedule.  Have breakfast when you want your body to start waking up and quit eating a couple hours before you want to fall asleep.  Even if this means eating at weird times as you a traveling back.  Much of your sleep/wake cycle is regulated by hormones and chemicals that your gut bacteria play a part in creating.  The bacteria living in your gut can’t see light though, so they use signals from you to tell what time it is.  When you eat, it signals to them that it is waking hours and they follow suit.
2. Wear glasses that block blue light.  Many people are familiar with the glasses like Felix Gray that block blue light from computer screens, but most probably don’t use this to their advantage for jet lag.  Just like eating signals to your gut bacteria that it’s time to be awake, blue light exposure tells them and your body that it is daylight.  This is why people wear glasses to block computer light at night.  If they don’t, they can have trouble sleeping because that light is a signal to your internal clock to produce cortisol.  Cortisol is a hormone in the body that spikes when you wake up and gradually decreases throughout the day until it hits rock bottom at night.  When it is low, you get sleepy.  (If you’re a person that suffers from mid-day fatigue, then you may see this dip in cortisol happen in the middle of the day on labs, which explains why you’re ready for a nap!)  If you wear blue blocking lenses when you want to start falling asleep and keep them off when you want to be wide awake, it will help adjust those cortisol patterns.
3. Take melatonin.  Just like blue light stimulates cortisol to make you feel awake, lack of blue light dampens cortisol and allows melatonin to rise.  When the sun goes down and your cortisol plummets, that’s melatonin’s signal to increase.  You should have high melatonin around the time you want to go to bed.  You can artificially mimic this by taking melatonin supplements before you want to go to bed.  This will make people drowsy.  Melatonin is a hormone, so you would not want to rely on this for long-term sleep aid, but it is helpful in resetting jet lag.  If you take too much, you could end up having vivid dreams or waking up with a “hang over.”  So, start with small doses and work your way up as needed.
4. Go outside.  Following the suns schedule is a powerful tool to get in synch with the normal rhythms of the Earth.  If you get up to watch the sunrise and go out to watch the sunset, you’d be amazed how quickly you fall into place.  This happens mostly because of the light exposure having an impact on your cortisol and melatonin ratios.
5. Exercise intensely when you want me to waking up. When you exercise, it raises cortisol levels just like light does, so if you time your exercise for when you want to be awake first thing, then your body will tend towards a cortisol spike during that time.  This will wake your body up, and help you fall asleep at night when the time is right.
6. Have caffeine in the morning.  Once again, we want cortisol to be spiking when you would be waking up.  Caffeine stimulates cortisol production, so having a cup of coffee when you WANT your body to be waking up will help put that circadian rhythm back on track.  That also means avoiding it when you would want your body to be getting sleepy.

These practical tips are easy to do if you think about them ahead of time and plan.  I can’t emphasize enough how important light exposure is in trying to reset your internal clock, so if you can do things that make your body think it’s light when you want to be awake and dark when you want to sleep, the better off you’ll be.  Shift work and time zone changes is one of the hardest thing you can do your body and actually contributes to earlier death and heart attacks.  So, while this is somewhat necessary at times for work or travel, you should try to avoid it as much as possible.  Your immune system actually functions on this same rhythm, so having your body produce cortisol at the wrong times will actually dampen your immune system during those times, too.  This is one reason many people get sick when traveling.  Not only are you often stuck on a plane with recycled air from tons of individuals, but you are throwing off your body’s normal rhythm to fight infections and create immune cells.  This is something to really consider especially if you have disorders of the immune system, like autoimmunity.  Your immune system reacts to your cues, so try to make them as easily translatable as you can to what normal cycles are.

I hope this helps!