Don't shoot the messenger!
Drinking Coffee Before You Fly
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If preparing for a flight was all just packing up and running to the terminal, we'd be professionals by now, especially during this busy holiday season; but we've come to realize that there are a lot of dos and don'ts when it comes to flying etiquette and know-how. The delicate nuances surrounding the best packing techniques, proper in-flight manners, and savvy seat selection have made us realize just how many things we didn't know about air travel. Now when it comes to being your healthiest self before boarding, it's incredibly important to pay close attention to what you're putting into your body. While we'd never argue that eating greasy fried foods before a five-hour flight is a good idea, we've learned an even more insidious sneak of a pre-flight no-no has been living right under our noses—wafting up its warm, caffeinated aromas, no less.

So, before you nurse your pre-flight exhaustion with a steaming cup of coffee while waiting at your gate, think again. Because that coffee might come back to haunt you mid-flight in a few different ways.

First, the most apparent side effect of drinking coffee, a mild diuretic, before a flight is that it dehydrates your body. Dehydration is bad news in terms of keeping air sickness at bay, preventing high altitude headaches, and avoiding getting post-flight illnesses. Not to mention, since airplane cabins are already dry, your skin and immune system are fighting a dehydrating atmosphere right off the bat.

According to Travel + Leisure, airline professionals also suggest limiting your caffeine intake because it will affect you more drastically at the high altitude than at sea level, which could make jitteriness and nausea more likely. It takes about five to six hours for half of the caffeine you ingest to wear off; so be weary of drinking coffee even a couple hours pre-flight.

A smaller (yet still worth mentioning) side effect is that coffee can cause a flare-up in those prone to heartburn. Travel puts stress on the body naturally through its irregular nature (your internal routine is thrown off), but it's worse when coupled with the dehydration that many travelers suffer from while flying. This makes the chance of coffee kicking up some heartburn symptoms much more likely during the flight for individuals who have both infrequent or chronic heartburn. Additionally, as we know, coffee is known to spur the digestive system into—er—action, and the last thing we want for travelers is an upset stomach during the flight that sends them marching to the cramped airplane restroom. Not ideal.

Flight attendants have already let us in on the secret that we shouldn't be drinking coffee during the flight (the reason is more than icky), so you can take that as a warning sign that coffee and flying? These two just don't belong together.

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We know that the Starbucks in the airport is often a beacon of hope after getting through security. (Trust us, we love coffee. We love coffee like Lorelei Gilmore loves coffee.) However, we aren't going to make ourselves miserable during our holiday travels for that fleeting jolt of joy. From now on, we'll just wistfully await until we've landed before sipping on that warm cup of Joe.