Heartburn pills are some of the most widely taken medications in the world, and many people stay on them for years. When headlines started linking them to dementia, a lot of long-term users understandably wondered whether they should worry. The research is less settled than those headlines suggested.
Proton pump inhibitors (PPIs) — acid-reducing medications such as omeprazole, esomeprazole, pantoprazole, and lansoprazole — have been linked to higher dementia risk in some large observational studies, but other well-designed cohorts and a later pooled analysis found no increased risk, even with high cumulative use. The studies can't prove that PPIs cause dementia, and the evidence as a whole doesn't show that they do. PPIs treat real conditions, so don't stop one abruptly; a better step is asking your doctor whether you still need it and at what dose.
Why PPIs Came Under the Microscope
PPIs reduce stomach acid and are used for reflux, ulcers, and other acid-related conditions. Because they're prescribed so often, and frequently long-term, researchers asked whether years of use might affect the brain. Most of the evidence comes from studies that follow large groups of older adults and compare dementia rates between PPI users and non-users. Those studies reached different conclusions.
Studies That Found a Link
An early pooled analysis of four observational studies looked at the question. When it restricted the analysis to cohort studies, it found a higher dementia risk among PPI users, with a pooled relative risk of about 1.44. A later population-based cohort pointed the same way. It reported dementia incidence of roughly 1.06 per 1,000 person-years in regular PPI users versus 0.51 in non-users, and the association appeared strongest in people who carry one copy of the APOE ε4 gene variant.
Studies That Didn't
Other researchers used more detailed medication records and reached a different answer. In one prospective study of 3,484 adults aged 65 and older, researchers drew on pharmacy data to measure how much PPI each person had taken over time. They found no increased dementia risk, even among people with high cumulative exposure, and the authors concluded the results don't support avoiding PPIs out of concern for dementia. A larger updated meta-analysis came to a similar conclusion. Pooling ten studies and more than 640,000 participants, it reported no increase in dementia or Alzheimer's risk among PPI users.
An honest limitation: every study above is observational, so none can show cause and effect. Several things can push results in either direction. People who take PPIs often have other health conditions and take other medications, which makes it hard to separate the effect of the drug from the effect of the illness. Studies that rely on insurance claims can miss over-the-counter PPI use, so exposure may be measured imperfectly. And people who see doctors more often tend to get diagnosed with dementia more often, which can create the appearance of a link. This is why the same question has produced both positive and negative results, and why researchers keep calling for better-designed studies.
What This Means for You
The honest summary is that a link hasn't been established, and a causal effect certainly hasn't been proven. At the same time, PPIs aren't meant to be taken indefinitely without a reason, and the authors of the cohort study above noted that long-term use carries other safety questions unrelated to dementia. A periodic check-in with your doctor makes sense on those grounds alone.
- Don't stop suddenly on your own Reflux symptoms can come back, and some people take a PPI for a condition where ongoing treatment matters. Any change is best planned with your doctor.
- Ask whether you still need it and at what dose Many people are started on a PPI for a short course and simply continue. Your doctor can tell you whether the original reason still applies and whether a lower dose or an as-needed approach might work.
- If you've taken one for years, ask about a vitamin B12 check Long-term PPI use can reduce B12 absorption in some people, and low B12 is a recognized, treatable contributor to brain fog.
- Look at the whole medication list If you're also taking medications with anticholinergic effects, the combined picture matters more than any single drug. A pharmacist can help review it.
The Bottom Line
Some studies link PPIs to a higher risk of dementia, but others, including one with detailed pharmacy records and a larger pooled analysis, found no added risk. Because all of this evidence is observational, it can't settle whether PPIs cause dementia, and the overall picture doesn't support alarm. The practical takeaway is simple: don't stop a PPI on your own, but do ask your doctor whether you still need it, at the lowest effective dose, and whether a B12 check makes sense if you've taken one for years.
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Get the Free Brain Health Mastery BundleFrequently Asked Questions
Do PPIs cause dementia?
That hasn't been shown. Some observational studies found a higher dementia risk in PPI users, but others, including a study using detailed pharmacy records and a larger pooled analysis, found no increase. Observational studies can't prove cause and effect, and differences between people who take PPIs and people who don't may explain some of the results.
Why do studies on PPIs and dementia disagree?
People who take PPIs often have other health conditions and take other medications, medication use is sometimes measured imperfectly, and people who see doctors more often tend to be diagnosed with dementia more often. These factors can push results in either direction, which is why researchers keep calling for better-designed studies.
Can long-term PPI use affect memory through low vitamin B12?
Long-term PPI use can reduce vitamin B12 absorption in some people, and low B12 is a recognized and treatable contributor to brain fog and memory problems. If you've taken a PPI for years, ask your doctor whether a B12 blood test makes sense.
Should I stop taking my PPI because of this research?
Not on your own. The evidence doesn't show that PPIs cause dementia, and stopping suddenly can bring reflux symptoms back or leave a condition untreated. A better step is asking your doctor whether you still need the medication and whether a lower dose is an option.
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