Living in the 21st century, there’s a lot that we take for granted. “Google” is a verb.
I have met adults who have never rented a video.
And we can get pretty much anywhere in the world in less than 24 hours. Often much less.
Air travel is so commonplace it’s become mundane- we don’t even think about it.
We’ve all heard the old saw that “you’re more likely to die in a car crash than in a plane…”
That’s true...and an important fact to hold onto for nervous flyers. Air travel is statistically very safe, and dwelling on the likelihood of a crash-landing in the Hudson isn’t really conducive to getting to LA or New York for that meeting.
BUT there are other, hidden health dangers of flying that we probably don’t think about enough.
In fact, flying is so hazardous to your health that a recent Harvard study found that flight crews, despite being healthier (on average) than the general population when it comes to classic risk factors like obesity, hypertension, diabetes, etc. have a higher risk of all cancers, especially reproductive cancers like breast and prostate cancer.
The same study also found that flight crews are at a higher risk of peripheral artery disease, sleep disorders, and certain mental health issues like depression.
What makes flying so hazardous to your health?
It turns out: a lot of things!
Radiation From Flying
First let’s talk about radiation. A typical commercial airliner will fly at altitudes between 31,000 to 38,000 feet on average. One of the reasons they fly at these heights is because the reduced atmosphere results in less resistance, so the plane can fly faster with less fuel. That’s good.
Not so good? That atmosphere the plane is escaping also normally shields us from harmful radiation. So when flying you’re trapped in a metal tube, without the normal protection of earth’s atmosphere, exposed to all kinds of UV and cosmic radiation.
How much radiation? The US Center for Disease Control (CDC) estimates that during a 6 hour flight (coast to coast) you’re exposed to about 0.035 milliSieverts (mSv) of radiation. For context, one chest x-ray exposes you to about 0.1 mSv of radiation, while a chest CT delivers about 7 mSV.
Ok...but what does that mean? According to the New England Journal of Medicine cumulative exposure to about 100 mSv causes a demonstrable increase in cancer risk. Experts say that we can start to quantify health risks at just 50 mSv.
We’re all exposed to about 2-3 mSv a year just walking around.
The International Commision on Radiological Protection (ICRP) recommends that workers in high radiation exposure jobs not be exposed to more than 20 mSv per year. For some insane reason, flight attendants’ exposure to radiation isn’t even monitored, even though the National Council on Radiation Protection (NCRP) reports that flight attendants have the highest average annual effective dose of any US radiation workers.
Why is radiation bad?
Basically the processes keeping your body alive are just a massive collection of ongoing (bio)chemical reactions. Radiation can disrupt these reactions, breaking the bonds between molecules and causing the production of harmful free radicals, like the hydroxyl radical. These free radicals can then cause chain reactions that harm other structures, like your DNA, causing mutations that can lead to cancer.
But radiation isn’t the only danger of flying at high altitudes…
Hypoxia While Flying
Remember the lack of atmosphere at high altitudes? Funny thing is...we need atmosphere to breathe. This is why airplane cabins are pressurized.
The problem? They’re pressurized to the equivalent of what it would be like if you lived at 8,000 feet.
Athletes spend time training at altitudes like 8000 feet because the lack of oxygen there makes it hard for our bodies to function. Over time (weeks to months) our bodies adapt. We start to produce more red blood cells, and we can become much more efficient at getting oxygen to our tissues.
Unfortunately (or I guess, fortunately), we don’t spend weeks to months on planes getting acclimated. So that means that for however long you’re in the air, you’re in a hypoxic (low oxygen) state.
You know what really likes oxygen? Our brains.
You know what happens when our brains don’t get enough oxygen? Brain damage.
So that’s bad.
You know what else can hurt your brain? Lack of sleep. Often when flying we can pass through multiple time zones leading to something we all now as jet lag, aka flight fatigue.
So what’s the big deal? Losing a little sleep never hurt anyone...or did it?
In the last couple of years neuroscientists have discovered a nifty little system inside of our brains called the glymphatic system. Glia are tiny little support cells that are basically the brain’s maintenance crew.
And they do a lot of their work while we’re sleeping. Scientists have discovered that our neural tissues shrink while we’re sleeping- maybe as much as 60%! The shrinkage makes a lot of room for glial cells to swoop in and scrub out all the waste that’s accumulated during the day. One of these waste products is beta-amyloid plaques.
Accumulation of these beta-amyloid plaques is seen in neurodegenerative diseases like Alzheimers. And when we’re sleep deprived, they don’t get cleaned out, and start to accumulate. What’s worse is that they accumulate in the area of the brain that’s responsible for deep sleep.
So as these plaques accumulate, they make your sleep quality worse, which leads to more accumulation. It’s a vicious cycle.
So a good night’s sleep may be your best bet to stave off Alzheimers and other forms of dementia!
But wait...there’s more.
Toxic Chemicals on Planes
Have you ever taken a deep whiff of recycled airline air and thought (mmm...that’s nice.)
That air is recycled throughout the cabin the entire time the plane is pressurized. That means you’re breathing every other passenger’s coughs, sneezes...farts...gross.
This means you’re also being exposed to any viruses, bacteria, etc. that other passengers may have brought on board.
But wait...surely the planes must be sanitized? Well...sort of. You know what airlines use to disinfect planes? Pesticides. So while you might avoid breathing in that rhinovirus germinating in 3B, you might be getting a nice dose of toxic chemicals instead.
Speaking of toxic chemicals, how do you feel about flame retardants? Because you’re sitting on them. Many airline seats are treated with flame retardants which are known to have toxic chemicals. So there’s that.
So if the cancer from radiation exposure, low oxygen-induced brain damage, sleep disruption or germs don’t get you, the pesticides and chemical flame retardants just might.
How To Protect Yourself When Flying
The (“good”?) news about these risks of flying is that they all have a common mechanism of injury: the production of free radicals and oxidative stress.
Normally our cells exists in a balance we call homeostasis. Free radicals are produced pretty much constantly by normal metabolic processes, and our cells pump out a steady stream of antioxidants to neutralize them. As long as this balance is maintained, no problem.
However, when external stressors (like any of the million you’re exposed to during an airline flight) cause even more production of free radicals, our natural defense system can’t keep up. The free radicals overpower our antioxidant system, and start to wreak havoc.
This is actually one of the hallmarks of most chronic disease processes.
What if there were a way to naturally boost your own antioxidant levels while you were travelling?
It turns out there is- in the last decade there has been a lot of research around a really exciting new medical breakthrough: molecular hydrogen.
Molecular hydrogen is composed of two diatomically bonded molecules of the hydrogen element, usually found as a gas. In 2007 researchers in Japan discovered that hydrogen gas has powerful physiological effects on the human body.
Over 1000 research studies since have validated the idea the hydrogen is actually a master antioxidant. It selectively targets the hydroxyl radical (one of the worst free radicals) and actually turns on your body’s own antioxidant system via activation of the NRF2 pathway.Molecular hydrogen will cause your cells to start pumping out glutathione, superoxide dismutase, and other antioxidant powerhouses.
Remember the dangers of brain damage from hypoxia? Researchers from Harvard Medical are currently using molecular hydrogen at Boston Children’s Hospital in cardiopulmonary transplant research, because it’s so effective at preventing brain damage from hypoxia.
Biohackers and medical experts for years now have been touting molecular hydrogen as the ultimate travel aid. Dr Joseph. Mercola argues that it can mitigate up to 80% of the damage incurred during an airplane flight from jetlag.
Experts recommend taking 1-2 molecular hydrogen tablets before flying, and again every hour in the air for best results.
Does this change how you think about air travel? Do you have any go-to flying hacks? Please share in the comments below!