Millions of people fly all across the globe every day. Although it is considered the safest mode of transportation, risk factors are still involved, and there are side effects to being 35,000 feet in the air. Simple Flying recently wrote about how much of a threat radiation poses to pilots and the most frequent fliers, but what about all travelers on the longest routes available?

Jet lag

Indeed, the most common symptom of a long-haul journey is jet lag. You’ve likely experienced this disconnect between your internal clock and the local time, even traveling a few time zones away. According to Dr. Paulo M. Alves, medical director for MedAire, who interviewed with The Healthy,

“The rule is that we need around one day for every hour of time zone we cross, so that means that after a six-hour transatlantic flight, we would need around six days for our cycles to be fully re-synchronized with the local time.”

Of course, some people get over this by preemptively changing their sleep schedule before a trip, while others try to adjust upon arrival. Eating meals at the proper local time can help get you accustomed to a new time zone, as can moving around in the sun in the early days of a trip far away from home.

Man sleeping on airport gate seats.
Photo: Colombo Photography/Shutterstock

Fatigue

Another common side effect of being airborne for long periods is mild fatigue. Although aircraft cabins are kept at pressures to mimic air between 6,000 and 8,000 feet, that’s still much higher than the average living altitude. And while most people will be fine existing in a high-altitude environment for long periods, those who are sensitive may feel mild hypoxia or low oxygen in body tissues.

This non-critical hypoxia may cause travelers to experience headaches and feel more tired. Bringing along some painkillers and a good travel pillow can provide some comfort just in case, but if you’re planning to take a long-haul trip, make sure to drink plenty of water before and during the flight. If you feel fatigued when flying, it’s best to avoid alcohol, caffeine, or anything that will dehydrate you.

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Ear, nose, and gut problems

Pressurization doesn’t just affect oxygen levels. During ascent and descent, as the cabin pressure changes, gas trapped in the body and sinuses react in turn. Typical problems, as a result, include earaches from the pressure difference on either side of the eardrum, headaches from expanding air inside the nasal sinuses, and the need to pass gas that swell in the gut. Fortunately, these are typically short-term issues only causing symptoms while increasing or decreasing altitude and don’t cause serious harm.

Dehydrated skin

Not only does the air pressure cause issues, but its low humidity can also cause discomfort. Keeping hydrated in the sky won’t just help prevent fatigue but also prevent your skin from drying up. Ideally, passengers should be drinking more water than usual. At the same time, onboard the plane, packing a moisturizing lotion just in case can be a lifesaver when you have dehydrated skin and 10 hours till arrival.

British Airways A320 Legroom
Photo: Jake Hardiman | Simple Flying

Blood clotting

The symptom travelers should look out for the most is painful or swollen legs. Sitting down in a tight seat for 13+ hours can sometimes lead to circulation issues, including swelling in the feet. According to The Healthy, the chance of your body forming blood clots increases when blood isn’t moving correctly, such as when onboard a long-haul flight.

Get up and walk around every few hours to get the blood moving again. If you’ve been drinking enough water to stay healthy while flying, a couple of trips to the lavatory might help. Even stretching and rotating your legs and feet can stimulate blood flow if you’re stuck in a seat that’s not easy to leave. And for those who have an underlying health condition, it may be worth talking to a doctor about compression socks for additional protection against circulation issues.

What are your thoughts on these side effects of taking long-haul flights? Have you ever experienced less common symptoms yourself? Let us know in the comments below.

Sources: The Healthy, The Conversation