Drinking alcohol while flying may seem like the height of luxury, often depicted in cinema as an indulgent experience. However, a recent study has highlighted the serious health risks associated with drinking alcohol while flying.

The study, published in the medical journal Thorax, suggests that the combination of alcohol and cabin pressure at cruising altitude may pose a risk to the heart health of sleeping passengers, especially on long-haul flights (flights of 6 hours and above).

Researchers found that when passengers fell asleep after drinking alcohol, their heart rates increased while their blood pressure dropped, even in young people with no significant medical history.

This condition is especially dangerous for people who have heart disease. The combination of alcohol and the low-pressure environment at high altitude rapidly decreases blood oxygen levels.

This results in hypobaric hypoxia, a condition in which the brain receives insufficient oxygen at high altitude, which can be life-threatening.

The findings showed that the combination of alcohol and artificial cabin pressurization caused SpO2 levels (oxygen saturation) to drop to an average of more than 85% at cruising altitude, while the heart rate increased to about 88 beats per minute during sleep as a compensatory response.

Those exposed to hypobaric hypoxia and alcohol also had shorter periods of REM (rapid eye movement, a type of sleep that occurs at intervals during the night) sleep.

“These results indicate that, even in young and healthy individuals, the combination of alcohol consumption and sleeping under hypobaric conditions places considerable stress on the cardiovascular system and may make symptoms more severe in patients with cardiac or pulmonary diseases,” the researchers wrote.