Don’t drink alcohol on the plane, experts warn. But if necessary, follow this advice.

Getting drunk on a plane is one of those bucket list items that sounds fun in theory—especially if it prefaces a much-needed vacation—but in reality, it’s much better to save the beers for the beach. (Although even that can be risky.) Drinking, in general, not good for you, but doing so at 30,000 feet in particular has different health implications than drinking it on land. So we asked experts to explain what happens to your body when you drink alcohol on a plane and why you might want to think twice before calling a flight attendant for a round or two of those mini bottles of booze.

You really get drunk faster

The higher the altitudes reached in an airplane, the lower the oxygen levels and atmospheric pressure will be, Dr., physician and co-founder of MAPS Centers for Pain Control, told Yahoo Life. At normal altitudes, oxygen binds to hemoglobin to transport oxygen throughout the body and keep vital processes running, including the body’s ability to release alcohol, he explains. “The lower our oxygen levels are, the harder it is to metabolize and eliminate alcohol,” he says.

Alcohol consumption also worsens already compromised oxygen levels “because it prevents some oxygen from binding to hemoglobin,” says Pontinen. This can cause dizziness, headache and even confusion. Obviously, these risks are not ideal for anyone to take; however, Dr. Leonardo Pianko highlights that people over 65 and people with health problems should be especially aware of these issues.

Alcohol can also hit you harder if you don’t eat before takeoff or if you just snack on filler foods with little nutritional value, like those free pretzels the flight attendants hand out. Whether you’re in the air or on the ground, “an empty stomach makes you get drunk faster,” notes Pontinen. “If there is no more food to digest, the stomach will have no choice but to open the valves and let the alcohol enter the intestine, where most absorption occurs.” To counteract these effects, he recommends consuming slower-digesting foods that contain healthy fats (think: nuts, hard-boiled eggs, or yogurt).

You are more likely to dehydrate

The air inside planes has low levels of humidity – about 10%-20% humidity compared to 35%-65% humidity you would find in more typical environments – and that dry cabin air can lead to dehydration, which can cause classic symptoms like dizziness, headache and fatigue, Dr. tells Yahoo Life. Add that to the fact that you may also drink less water than usual on a plane while you’re busy watching movies or napping. Consuming alcohol beyond this can increase the risk of dehydration. Pontinen adds that alcohol is also a diuretic, which can intensify dehydration.

There is an increased risk of blood clots

Alcohol can cause dehydrationwhich, when combined with prolonged sitting during flights, increases the risk of developing blood clots, also known as deep vein thrombosis. “It’s not just the alcohol,” notes Pianko. “It’s the effect of alcohol combined with what you eat, the medications you take, your digestion and your sleep. What concerns me most is that individuals who drink alcohol take a sleeping pill and cross their legs, which can lead to increased blood clotting.”

Drinking and then sleeping on planes can be harmful to your heart

In general, alcohol increases your risk of heart disease because it weakens your heart muscles and increases your blood pressure, explains Pontinen. One June 2024 to study explored this by examining the combined effects of cabin pressure and alcohol consumption and then sleep on long flights in both healthy people and those with pre-existing heart problems. The results showed that even healthy participants experienced heart strain in the form of reduced blood oxygen levels and increased heart rate. This not only caused hypoxia – or low blood oxygen levels found at higher altitudes – but also disrupted participants’ deep sleep.

These effects pose a particular risk to those who already have heart problems. Based on their findings, the researchers recommend that people with obstructive sleep apnea or obesity hypoventilation syndrome, which is a breathing disorder, avoid alcohol in the 12 hours before your flight. But in general, researchers say it may be beneficial to restrict access to alcoholic beverages on flights, given the potential risks to heart health.

While it’s best to avoid alcohol entirely while flying, if you still want to drink, Sharp recommends drinking a glass of water for every alcoholic drink consumed in the air. And, of course, drink in moderation, which Sharp says is no more than two drinks — even on long-haul flights.