About 850 million people board airline flights each year — often with some certainty that they will land feeling worse than they when they took off. 
Air travel sucks… Flying messes with your circadian rhythms as you shift time zones, increases stress hormones, is uncomfortable, and raises your risk of blood clots. It’s also dehydrating and your risk of getting sick from flying is actually pretty high. Because air gets filtered from the front of the plane to the back, your risk is even higher in economy class.
The human body just wasn’t designed to be inches away from dozens of other humans, breathing the same air in a metal tube six miles above the surface of the earth. 
But don’t worry.
There are some simple ways to help you stay Bulletproof at 30,000 feet.
#1 Drink more water
Airlines cycle the air in the cabin of a jet about every two minutes. This leaves the air breathable, but also very dry. The cabin can end up being as low at 6 percent humidity, which is drier than any desert. We tend to be more comfortable around 50 percent. [3, 4]
At this low level of humidity, it’s easy to lose water. Being dehydrated can dry up your mucous membranes, irritate your eyes, nose, and throat and weaken your immune system. Avoid dehydration by limiting caffeine and alcohol before and during your flight and drinking a ton of water. You may need to go to the bathroom more, but that’s not such a bad thing as you’ll learn in tip #4.
#2 Pack your lunch (and your glutathione)
Not only are you crammed up against hundreds of other passengers who may not be in great health, but airplane surfaces don’t get much cleaning between flights. That means you could be sharing germs with passengers from several flights.
To address this, some airlines spray antibacterial and antiviral chemicals into the air to avoid the spread of infectious disease. But they won’t tell you what’s in these chemicals, so they may, in fact, be doing more harm than good. Worse, they could be a danger to passengers with asthma or other breathing difficulties. 
You can’t do much about the air quality, but you can ensure that your immune system is up to the task of fighting off bugs and toxic substances.
Your diet is essential for a robust immune system, so avoid indulging in cheat days while traveling and pack your food when possible. Brain Octane on salads, sushi, vegetables and meat will give your body the energy it needs to thrive and help to keep you fuller longer. Good thing it now comes in these travel-friendly, leak-proof 3-oz bottles.
The physical and emotional stress of travel means your immune system is working in overdrive, which may lead to a quick depletion of your master antioxidant glutathione and a subsequent immune system crash. Vitamins A, D, and C, plus zinc and glutathione will help to keep your immune system strong.
#3 Cover your ears
Many people don’t plan for the noise stress they will encounter while flying. Noise pollution from a passenger airplane is around 80 decibels, which is enough to trigger your stress response.  This stress response links prolonged airplane travel to things like hypertension, cardiovascular disease, and even psychological disorders.
In one study, rats exposed to long-term aircraft noise experienced inhibited mobility and increased anxiety.  Noise exposure can lead to cumulative hearing loss over time, meaning the more exposure, the more hearing loss will continue to grow. And once it’s gone, it’s lost forever. Other data suggests that prolonged noise stress can damage the temporal lobe, which is responsible for sensory processing, language and emotion processing.
Lower your stress response by wearing earplugs or noise-reducing headphones – especially during long flights.
#4 Invest in compression socks
Deep vein thrombosis, or DVT, is a blood clot that usually forms in the legs. These clots develop when there’s poor circulation to the legs, low air pressure, dehydration, and little leg movement. Long-distance air travel may increase the risk of DVT 2- to 4-fold. [8,9] Symptoms include swelling or redness, but most people who form clots won’t feel anything.
Most of the time these dissolve without becoming harmful, but they can be fatal in rare cases when clots dislodge and travel throughout the body.
You’re most at risk for DVT if you’re overweight or have circulatory problems, but anyone can be affected, especially those traveling for longer than 4-6 hours without much movement.
Avoid clot formation by keeping hydrated and standing up and walking around as much as possible. Flex your feet and legs often to keep your blood flowing. Finally, consider wearing compression socks to avoid swelling, which can encourage clotting.
Most people feel they have to fly for work or family reasons. Many dread the experience – not to mention the jet lag. But everyone can take steps to feel and perform better when traveling by air.
So next time you’re catching a flight, pack some empty water bottles to fill at the airport, take your supplements, and think about wearing ear protection and compression socks.
Read more about hacking airplane travel: