Constant acid reflux usually means something is physically or functionally wrong with the valve between your stomach and esophagus, and one or more factors in your daily life are making it worse. If you experience heartburn or regurgitation two or more days a week, that crosses the threshold from occasional heartburn into gastroesophageal reflux disease, or GERD, a condition affecting 10 to 20% of adults in Western countries. The good news: once you understand why it keeps happening, most of the causes are manageable.
How the Anti-Reflux Valve Fails
At the bottom of your esophagus sits a ring of muscle about 3 to 5 centimeters long that stays contracted at rest, forming a seal against your stomach contents. When this valve relaxes at the wrong time or can’t maintain enough pressure, acid washes upward. The single most common reason for reflux, in both healthy people and those with GERD, is temporary, inappropriate relaxation of this valve. Your stomach stretches after a meal or swallows air, and the valve opens briefly when it shouldn’t.
In some people, the valve’s resting pressure is simply too low to hold back stomach acid between meals. Others have normal valve pressure but experience far more of these spontaneous relaxations than average, especially after eating. Either way, the result is the same: acid, digestive enzymes, and sometimes bile flow into the esophagus where they don’t belong.
Hiatal Hernia: A Hidden Structural Cause
Between 50% and 94% of people with GERD have a hiatal hernia, where the upper part of the stomach pushes up through the opening in the diaphragm. Your diaphragm normally acts as a second layer of protection, squeezing around the valve from the outside. When the stomach slides upward, it displaces the valve and pulls it away from the diaphragm’s reinforcement. This compromises both parts of your anti-reflux barrier at once, which is why hiatal hernias are so strongly linked to persistent symptoms.
Many people have small hiatal hernias without knowing it. They often produce no symptoms on their own but make your reflux barrier weaker and more vulnerable to other triggers.
How Body Weight Drives Reflux
Carrying extra weight, particularly around the abdomen, is one of the strongest and most consistent risk factors for daily reflux. Abdominal fat doesn’t just sit passively. It transmits gravitational force into the abdominal cavity, raising the pressure around your stomach. Studies using pressure measurements have confirmed that people with obesity have significantly higher intra-abdominal pressure than lean individuals. That extra pressure pushes stomach contents upward against the valve.
Obesity also changes the stomach itself. People carrying excess weight tend to have larger gastric capacity, meaning the stomach holds more volume, which increases the likelihood of those inappropriate valve relaxations after meals. Obesity also raises the risk of developing a hiatal hernia over time, compounding the problem. Even modest weight gain can shift reflux from occasional to persistent, and weight loss is one of the most effective long-term interventions.
Foods, Drinks, and Habits That Keep It Going
Certain foods lower your valve’s resting pressure or trigger it to relax more often. High-fat meals are among the worst offenders, slowing stomach emptying and increasing the time acid sits near the valve. Coffee and other caffeinated drinks, alcohol, and carbonated beverages all contribute. Large meals stretch the stomach more than small ones, creating more opportunities for the valve to open inappropriately.
Eating close to bedtime is especially problematic. When you lie down with a full stomach, gravity no longer helps keep acid where it belongs. Smoking also weakens the valve and reduces saliva production. Saliva is mildly alkaline and helps neutralize any acid that does reach the esophagus, so less of it means slower clearing of refluxed acid.
Medications That Can Worsen Reflux
Several common medications either irritate the esophageal lining directly or weaken the valve. NSAIDs like ibuprofen and aspirin disrupt the protective lining of the esophagus, making it more vulnerable to acid damage. The antibiotic doxycycline is one of the most frequent culprits for drug-related esophageal irritation, particularly if taken without enough water or right before lying down. Iron supplements, vitamin C tablets, certain blood pressure medications, and bisphosphonates (used for osteoporosis) can all cause similar problems. If your reflux worsened after starting a new medication, that connection is worth exploring with your prescriber.
Why Reflux Gets Worse at Night
Nighttime reflux tends to be more damaging because you swallow less frequently during sleep, produce less saliva, and lie flat for hours. A systematic review of sleep position studies found that sleeping on your left side significantly reduces both the amount of acid reaching the esophagus and how long it stays there, compared to sleeping on your right side or on your back. Sleeping on your right side performed no better than sleeping flat. The likely reason: when you lie on your left, your stomach sits below the valve opening, so acid pools away from it rather than against it.
Elevating the head of your bed by about 6 inches (using blocks under the bed frame, not just extra pillows) also helps by enlisting gravity to keep acid in the stomach overnight.
How Reflux Treatments Compare
Over-the-counter antacids neutralize acid that’s already been produced and work within minutes, but their effect is short-lived. H2 blockers (like famotidine) reduce acid production and work for longer stretches, but they have real limitations for persistent reflux. Proton pump inhibitors, or PPIs (like omeprazole), block acid production at its final step and are substantially more effective.
In a meta-analysis of 33 clinical trials with over 3,000 patients, PPIs relieved symptoms in 83% of patients compared to 60% with H2 blockers. For healing esophageal damage, the gap was even wider: PPIs healed erosive esophagitis in about 82% of patients at eight weeks, versus 52% for H2 blockers. PPIs achieved more healing in just two weeks than H2 blockers managed in eight. For someone dealing with reflux every day, this difference matters.
That said, PPIs work best as a tool for healing and symptom control, not necessarily as a permanent solution. Many people benefit most from a combination of medication to get symptoms under control and lifestyle changes to address root causes like weight, meal timing, and sleep position.
What Happens If Chronic Reflux Goes Untreated
Daily acid exposure takes a cumulative toll on the esophageal lining. The progression typically starts with inflammation (erosive esophagitis), which can advance to ulceration and scarring. About 10% of people with untreated erosive esophagitis develop strictures, where scar tissue narrows the esophagus enough to make swallowing difficult.
The more concerning long-term risk is Barrett’s esophagus, where the cells lining the lower esophagus change type in response to chronic acid exposure. In the general population, Barrett’s is uncommon, affecting less than 1% of people. But among those with chronic GERD, prevalence jumps to 7 to 12%. People who have had reflux symptoms for more than 10 years have a prevalence exceeding 20%. Barrett’s esophagus is significant because it’s the primary risk factor for esophageal adenocarcinoma, a type of cancer whose incidence nearly quintupled between 1975 and 1995. Chronic GERD carries roughly an eightfold increase in risk for this cancer compared to people without reflux.
These numbers aren’t meant to alarm you. The absolute risk of cancer remains low even with Barrett’s, estimated at roughly one case per 200 to 285 patient-years of follow-up. But they underscore why persistent, daily reflux deserves more than just toughing it out.
Putting the Pieces Together
Constant reflux is rarely caused by a single factor. It’s usually a combination: a valve that’s somewhat weak or prone to inappropriate relaxation, made worse by one or more amplifiers like excess abdominal weight, a hiatal hernia, late-night eating, or a medication that relaxes the valve or irritates the lining. The reason your reflux is constant rather than occasional is that enough of these factors are present simultaneously to overwhelm your esophagus’s ability to cope.
The most effective approach addresses multiple contributors at once. Losing abdominal weight reduces the pressure forcing acid upward. Eating smaller meals earlier in the evening limits how much acid is available when you lie down. Sleeping on your left side with the bed elevated protects you overnight. And if those changes aren’t enough on their own, acid-suppressing medication can bridge the gap while the underlying causes are managed.