Frequent heartburn happens when stomach acid repeatedly flows back into your esophagus, and it almost always points to a pattern, not just bad luck. If you’re experiencing it two or more times a week, you likely have gastroesophageal reflux disease (GERD), a chronic condition with identifiable causes that can be addressed. The key to stopping the cycle is understanding what’s actually going wrong in your body and which of your habits, anatomy, or medications might be driving it.
What’s Happening Inside Your Body
At the bottom of your esophagus sits a ring of muscle that acts like a one-way valve. It opens to let food into your stomach, then closes to keep acid from splashing back up. When this valve weakens or relaxes at the wrong time, acid escapes upward and burns the lining of your esophagus. That burning sensation is heartburn.
Several things can cause this valve to malfunction. Your diaphragm, the large muscle separating your chest from your abdomen, normally reinforces the valve by squeezing around it. If that reinforcement weakens, even small increases in abdominal pressure (from bending over, straining, or carrying extra weight around your midsection) can push acid upward. Smoking and alcohol directly reduce the resting pressure of this valve, making it easier for acid to escape even when you’re sitting still.
A Hiatal Hernia May Be Involved
One of the most common structural causes of persistent heartburn is a hiatal hernia. This happens when the upper part of your stomach pushes up through the small opening in your diaphragm where the esophagus passes through. When the stomach sits partly above the diaphragm instead of entirely below it, the natural pressure barrier that keeps acid in place is compromised. A small hiatal hernia often causes no symptoms at all, but a larger one allows food and acid to back up readily into the esophagus.
Many people with hiatal hernias don’t know they have one. It’s typically discovered during an endoscopy or imaging for another reason. If your heartburn has been constant for years despite lifestyle changes, this is one of the things worth investigating.
Foods and Drinks That Weaken the Valve
Certain foods don’t just “disagree with you.” They have measurable effects on the valve at the base of your esophagus. Coffee is one of the most studied triggers. Research shows it reduces resting valve pressure by roughly 30% in healthy people, dropping it from about 19 mmHg to under 14 mmHg within an hour. In people who already have reflux disease, the effect is even more dramatic: valve pressure drops from around 9 mmHg to just 5.5 mmHg, which is barely enough to hold anything back. Interestingly, even coffee adjusted to a neutral pH (removing its acidity) still caused this pressure drop, meaning the problem isn’t just the acid in the coffee itself.
Fatty foods slow down how quickly your stomach empties. The longer food sits in your stomach, the more opportunity acid has to push upward. Alcohol reduces valve pressure through a similar mechanism to coffee. Chocolate contains compounds that relax the valve as well. These aren’t just anecdotal triggers; they have pharmacological effects on the muscle tone that keeps acid where it belongs.
Medications That Make It Worse
If your heartburn started or worsened around the time you began a new medication, that’s worth paying attention to. Two separate mechanisms are at play. Some drugs directly irritate the esophagus as they pass through it: common pain relievers like ibuprofen and aspirin, certain antibiotics, iron supplements, and osteoporosis medications taken by mouth all fall into this category.
Other medications weaken the esophageal valve itself, increasing the amount of acid that escapes. Blood pressure medications (particularly calcium channel blockers and nitrates), certain antidepressants, sedatives, opioid painkillers, and progesterone all reduce valve tone. If you’re taking any of these and dealing with constant heartburn, it’s worth discussing alternatives with whoever prescribed them.
Why It’s Worse at Night
If your heartburn peaks when you lie down or wakes you up at night, there’s a clear mechanical explanation. When you’re upright, gravity helps keep stomach contents down. When you’re flat, that advantage disappears, and liquid in your stomach can flow freely toward the valve. In people with a weakened valve or hiatal hernia, nighttime reflux often occurs through “free reflux,” where the valve pressure is essentially absent, rather than through the brief relaxation episodes that cause daytime symptoms.
Your body also has a harder time clearing acid at night. During the day, each time you swallow, saliva (which is naturally alkaline) washes down the esophagus and neutralizes residual acid. At night, you swallow far less often, and saliva production drops. Research on nighttime reflux shows that acid clearance is significantly slower between the third and fifth hours of sleep, meaning acid that reaches your esophagus in the middle of the night can sit there much longer, causing more damage and more intense symptoms.
Elevating the head of your bed by six inches (using blocks under the legs, not just extra pillows) restores some of gravity’s protective effect. Eating your last meal at least three hours before lying down gives your stomach time to partially empty.
Smoking Compounds the Problem
Smoking affects heartburn through multiple pathways at once. Nicotine reduces the resting pressure of the esophageal valve, making reflux more likely. It also reduces the bicarbonate content of your saliva, which is the main way your esophagus neutralizes acid that does escape. The result is a double hit: more acid gets through, and your body is less able to clear it. On top of that, smoking increases the time it takes for acid to be neutralized once it’s in the esophagus. People who smoke and have heartburn often see significant improvement after quitting, sometimes more than they’d get from dietary changes alone.
Excess Weight and Abdominal Pressure
Carrying extra weight, particularly around the abdomen, increases the pressure inside your abdominal cavity. That added pressure pushes against your stomach and forces acid upward through the valve. This is one reason heartburn often develops or worsens during pregnancy (along with the effect of rising progesterone levels, which relax the valve). Even modest weight gain concentrated around the midsection can be enough to tip someone from occasional heartburn to chronic symptoms.
When Heartburn Signals Something Serious
Occasional heartburn after a heavy meal is normal. Heartburn that happens twice a week or more crosses into GERD territory and means the esophagus is being exposed to acid frequently enough to risk real damage. Over time, chronic acid exposure can cause narrowing of the esophagus, erosions, or cellular changes in the esophageal lining that require monitoring.
Certain symptoms alongside heartburn warrant prompt attention: difficulty swallowing or a sensation of food getting stuck, unintentional weight loss, persistent vomiting, or chest pain accompanied by shortness of breath or pain radiating to the jaw or arm. That last combination can mimic a heart attack and should be treated as one until proven otherwise. If you’re reaching for over-the-counter antacids more than twice a week, that alone is a signal that something beyond occasional indigestion is going on.