Acid reflux, often described as heartburn, is a condition where stomach acid flows back into the esophagus, causing irritation and discomfort. When this occurs frequently, it is diagnosed as Gastroesophageal Reflux Disease (GERD). For people prone to this issue, flying can exacerbate symptoms, as air travel introduces environmental and behavioral factors that challenge the body’s normal digestive process. The pressurized cabin atmosphere and forced immobility create conditions that make acid backflow more likely.
How Cabin Conditions Affect Digestion
The central cause of flight-related digestive distress is the change in atmospheric pressure within the aircraft cabin. Commercial airliners maintain a cabin pressure equivalent to an altitude between 5,000 and 8,000 feet above sea level, significantly lower than ground pressure. This reduction in ambient pressure causes the volume of gas trapped within the body’s cavities to expand. Gas present in the stomach and intestines can expand by up to 30% during a flight to a typical cruising altitude.
This expansion of gastrointestinal gas leads to increased pressure inside the abdomen, known as barotrauma. The resulting intra-abdominal pressure pushes upward against the diaphragm and the lower esophageal sphincter (LES), the muscular ring that acts as a valve. When pressure on the stomach side of the LES increases, the sphincter is more likely to relax or open inappropriately. This allows acidic stomach contents to escape into the esophagus and trigger reflux symptoms.
Another factor is the extremely low humidity in the cabin, often ranging between 1% and 15%. This dry air can lead to mild dehydration and the drying of mucous membranes. While not a direct cause of acid reflux, dehydration can thicken mucus and impair the natural clearance mechanisms that wash acid back down into the stomach. This contributes to a feeling of throat irritation.
Travel Habits That Worsen Reflux Symptoms
The way travelers behave before and during a flight significantly contributes to symptom flares, independent of the cabin environment. Prolonged sitting is a major factor because it slows the movement of food through the digestive tract. When a person sits for many hours, especially with a slouched or hunched posture, the abdomen is compressed.
This hunched position directly increases intra-abdominal pressure, mechanically forcing stomach contents toward the LES. Tight clothing, like a fastened seat belt, further exacerbates this compression. The combination of physical compression and lack of gravity’s assistance removes natural barriers to acid backflow.
Travel often involves stress and hurried eating, both known reflux triggers. Travel-related anxiety can increase stomach acid production due to nervous system stimulation. Passengers often consume gas-producing items like carbonated beverages or chew gum, which introduces more air into the digestive system and worsens altitude-related gas expansion. Many common airport or in-flight meals are high in fat, which delays gastric emptying, keeping acid in the stomach longer and increasing the chance of reflux.
Strategies for Symptom Relief While Flying
Managing reflux while flying begins with strategic planning of meals and medication timing. Proton pump inhibitors (PPIs), which are often prescribed for frequent reflux, work best when taken 30 to 60 minutes before a meal, as they target the proton pumps when they are most active. If you take a daily PPI, timing it to your first meal on travel day ensures maximum acid-suppressing effect during the flight.
For those who experience predictable, occasional heartburn, an H2 receptor antagonist (H2 blocker) can be taken as a prophylactic measure before the flight. These medications have a quicker onset of action than PPIs and can be taken on an as-needed basis. Travelers should fast for at least two to three hours before boarding to ensure the stomach is relatively empty during the pressure changes of takeoff.
In-flight behavior and food choices require mindful adjustment to reduce abdominal pressure. Avoid carbonated drinks, chewing gum, and hard candies, as these introduce excess air into the stomach. Opt for small, bland, non-acidic snacks like plain crackers or bananas instead of standard high-fat airline meals.
Maintaining proper posture is an effective physical strategy to manage symptoms in the air. Keep your body as upright as possible, avoiding the tendency to slump or recline excessively, which compresses the abdomen. Choosing an aisle seat allows for frequent, brief periods of walking, which stimulates digestion and helps relieve trapped gas. Carry a quick-acting antacid, such as a chewable tablet, for immediate relief from breakthrough symptoms.