Gastric reflux, commonly called acid reflux or GERD (gastroesophageal reflux disease), is a condition where stomach acid flows backward into the esophagus, the tube connecting your mouth to your stomach. It affects roughly 825 million people worldwide, with about 45 million cases in North America alone. Most people experience occasional acid reflux, but when it happens frequently, typically twice a week or more, it crosses into GERD territory and can start causing real damage.
How Reflux Happens
At the bottom of your esophagus sits a ring of muscle called the lower esophageal sphincter. This muscle acts like a one-way valve: it opens to let food into your stomach, then closes to keep stomach acid where it belongs. In gastric reflux, this valve either relaxes when it shouldn’t or doesn’t close tightly enough, allowing acid to wash back up into the esophagus. Unlike the stomach, which has a thick protective lining, the esophagus has no defense against acid. That’s what causes the burning.
Several factors weaken this valve. Excess body weight puts pressure on the abdomen, pushing stomach contents upward. Pregnancy does the same thing. A hiatal hernia, where part of the stomach slides above the diaphragm, physically repositions the valve so it can’t close properly. Smoking relaxes the sphincter directly, and so do certain medications like some blood pressure drugs and sedatives.
Common Symptoms
The hallmark symptom is heartburn: a burning sensation behind the breastbone that often worsens after eating or when lying down. Regurgitation, where you taste acid or partially digested food in the back of your throat, is the other classic sign. Many people also feel a lump in their throat, chest pain that can mimic a heart attack, or difficulty swallowing.
What surprises most people is how far beyond the chest reflux symptoms can reach. Acid vapor can travel up into the throat, voice box, and airways without ever causing heartburn. Chronic cough is linked to reflux in 21% to 41% of cases. Persistent sore throat and chronic laryngitis show up in as many as 60% of reflux patients, and about 10% of people who see an ear, nose, and throat specialist for hoarseness turn out to have reflux as the underlying cause. That sensation of a lump in the throat (sometimes called globus) is tied to reflux in up to 50% of cases. Some people also develop worsening asthma, sinusitis, or dental erosion from acid reaching the mouth.
Foods and Habits That Trigger Reflux
Certain foods relax the esophageal sphincter and slow digestion, letting food sit in the stomach longer and increasing the chance of acid escaping. The major culprits, according to Johns Hopkins Medicine, include high-fat, salty, and spicy foods: fried food, fast food, pizza, fatty meats like bacon and sausage, cheese, and processed snacks. Tomato-based sauces, citrus fruits, chocolate, peppermint, and carbonated drinks all cause the same problem. Even whole milk can aggravate reflux because of its fat content.
Beyond diet, eating large meals, lying down within two to three hours of eating, and wearing tight clothing around the waist all increase pressure on the stomach. Alcohol and smoking both relax the sphincter independently of food.
How Reflux Is Diagnosed
For most people, a doctor can diagnose GERD based on symptoms alone, especially if heartburn and regurgitation respond to a trial course of acid-reducing medication. When symptoms are unclear, don’t respond to treatment, or suggest complications, more specific testing comes into play.
The most definitive test is pH monitoring, where a small sensor placed in the esophagus measures acid levels over 24 to 48 hours. The test tracks what percentage of time the esophageal pH drops below 4.0, which is the threshold for acid exposure. If that number exceeds 4.3% of the recording time, reflux is confirmed. An upper endoscopy, where a thin camera is passed down the throat, lets a doctor directly see whether acid has damaged the esophageal lining and check for complications.
Over-the-Counter and Prescription Treatment
Treatment typically starts with lifestyle changes and moves to medication if symptoms persist. There are two main categories of acid-reducing drugs, and they work quite differently.
The first option is H2 blockers (sold under names like famotidine). These work by blocking one of the chemical signals that tells your stomach to produce acid. They kick in relatively quickly and can be taken as needed, making them useful for occasional flare-ups. The downside is that your body can develop tolerance to them within as few as three days, meaning they become less effective with regular use, sometimes even when the dose is increased.
The stronger option is proton pump inhibitors, or PPIs (like omeprazole and lansoprazole). These permanently shut down the acid-producing pumps in the stomach lining, making them the most powerful acid suppressors available. The trade-off is that they need to be taken daily for four to eight weeks to reach full effectiveness, because not all acid-producing cells are active at the same time. Taking a PPI only when you feel symptoms won’t reliably control reflux. For people with frequent or severe reflux, PPIs are the standard treatment.
Antacids like calcium carbonate neutralize acid that’s already in the stomach. They provide the fastest relief but wear off quickly and don’t prevent reflux from happening.
Lifestyle Changes That Help
Medication works best alongside practical adjustments. Losing even a modest amount of weight, if you’re carrying extra, reduces pressure on the stomach and can significantly improve symptoms. Elevating the head of your bed by six to eight inches (using a wedge or bed risers, not just extra pillows) helps gravity keep acid down at night. Eating smaller meals, finishing dinner at least three hours before bed, and avoiding your personal trigger foods all reduce the frequency of episodes.
For some people, these changes alone are enough to control symptoms without long-term medication.
Long-Term Risks of Untreated Reflux
Occasional heartburn isn’t dangerous. Chronic, untreated reflux is a different story. Repeated acid exposure can inflame and erode the esophageal lining, a condition called esophagitis, which can cause painful swallowing and, over time, narrowing of the esophagus (strictures) that makes food feel like it’s getting stuck.
The most serious long-term complication is Barrett’s esophagus, where the cells lining the lower esophagus change to resemble intestinal tissue in response to ongoing acid damage. Barrett’s itself doesn’t cause symptoms, but it’s considered a precancerous condition. The risk of it progressing to esophageal cancer is low on an individual basis: about 0.12% to 0.40% per year for people without any precancerous cell changes. That risk climbs to roughly 1% per year if early precancerous changes are detected, and above 5% per year if advanced precancerous changes are present. These numbers are small in any given year but add up over decades, which is why people with Barrett’s esophagus undergo periodic monitoring with endoscopy.
The good news is that effective acid control, whether through medication, lifestyle changes, or in some cases surgery to reinforce the esophageal valve, can halt the damage and allow the esophagus to heal.