Your Heartburn Might Not Be Too Much Acid — It Could Be Too Little

This one blew my mind when I first heard it — and then made complete sense.

Most people with heartburn reach for an antacid. Their doctor might prescribe a proton pump inhibitor. The assumption everyone makes — including most doctors — is that heartburn means too much acid.

But what if the problem is actually the opposite?

The counterintuitive truth about stomach acid

Your stomach is supposed to be extremely acidic — pH 1.5 to 3.5. That level of acidity is what allows your stomach to break down protein, kill pathogens, and signal the rest of your digestive system to do its job.

When stomach acid is low — a condition called hypochlorhydria — food doesn't break down properly. It sits in your stomach longer than it should, fermenting and producing gas. That gas creates pressure. That pressure pushes stomach contents upward toward your esophagus.

The solution to too much pressure isn't to reduce acid further. But that's exactly what antacids and PPIs do.

Why this matters long term

Stomach acid does a lot more than digest food. It's your first line of defense against pathogens — bacteria and parasites that come in through food and water get destroyed by healthy stomach acid. Low stomach acid means more of those get through.

It's also essential for absorbing certain nutrients — particularly B12, iron, magnesium, and zinc. These nutrients require an acidic environment to be properly extracted from food and absorbed through the gut wall.

Long-term use of acid-reducing medications is associated with increased risk of B12 deficiency, magnesium deficiency, increased susceptibility to certain gut infections, and reduced bone density — worth a conversation with your doctor about the long-term picture.

What causes low stomach acid

Low stomach acid is actually really common, especially as we age. After 40, stomach acid production naturally declines. Chronic stress reduces it. H. pylori infection — estimated to affect over half the world's population — directly damages the cells that produce stomach acid.

Other contributors include eating too fast, not chewing thoroughly, zinc deficiency (zinc is required to produce stomach acid), and chronic use of antacids — which can create a cycle where suppressing acid further reduces the stomach's ability to produce it.

Symptoms worth paying attention to

Low stomach acid and high stomach acid can feel surprisingly similar — which is part of why it gets misdiagnosed. Signs that might point toward low stomach acid rather than high:

• Heartburn that's worse after eating protein-heavy meals
• Feeling full very quickly or for a long time after eating
• Bloating and gas shortly after eating
• Burping after meals
• Nausea after taking supplements
• Undigested food visible in stool
• Nutritional deficiencies despite eating well — particularly B12, iron, or magnesium

The connection to gut health

Low stomach acid is one of the most common underlying factors in gut dysbiosis and SIBO — the bacterial overgrowth that causes chronic bloating. When the stomach isn't acidic enough, bacteria that should be killed in the stomach make it through to the small intestine where they don't belong.

This is why some people treat their bloating for years without resolution — they're treating the downstream problem without addressing the upstream cause.

What to bring to your doctor

This is definitely a conversation to have with your doctor — not something to figure out on your own. But it is worth having, especially if you've been on acid-reducing medication long-term and you're still not feeling well.

• Could low stomach acid be contributing to my symptoms rather than high acid?
• Has anyone tested me for H. pylori?
• Could my heartburn be related to gut motility or pressure rather than acid production?
• If I've been on a PPI long-term, should we monitor my B12 and magnesium levels?

Your gut is trying to tell you something. Sometimes the answer is the opposite of what seems obvious.