Hypochlorhydria is a deficiency of stomach acid. If you don’t have enough stomach acid, you can’t digest food properly or absorb its nutrients. This leads to indigestion, malnutrition and sometimes bacterial overgrowth. Fortunately, hypochlorhydria is relatively simple to test and treat.
Hypochlorhydria means low stomach acid — specifically, low hydrochloric acid (HCI), which is the most powerful acid your stomach produces. Hydrochloric acid plays an important role in your digestion and immunity. It helps break down protein and absorb essential nutrients, and it helps control viruses and bacteria that might otherwise infect your stomach.
If you have hypochlorhydria, you’ll have trouble digesting food properly, especially protein. Over time you can develop serious nutritional deficiencies. You’ll also be prone to infections, which can cause further damage to your stomach and digestive system.
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“Hypo-” means “low.” “Hyper-” means “high.” Hypochlorhydria means your stomach isn’t producing enough hydrochloric acid. Hyperchlorhydria means it produces too much. In the U.S., people most often attribute their digestive problems to hyperchlorhydria, and they often use medication to suppress their stomach acid. But in fact, symptoms of chronic acid reflux, laryngopharyngeal reflux or heartburn can also be caused by hypochlorhydria. Poor digestion from the lack of stomach acid can create gas bubbles that rise into your esophagus and throat, carrying stomach acid with them. Even trace amounts of acid in your throat can feel like too much.
Stomach acid is necessary for digestion and absorption of protein, vitamin B12 and several minerals. When your body is no longer able to break down and absorb these nutrients, you end up with undigested food and nutritional deficiencies. Protein and vitamin B12 deficiencies lead to iron deficiency anemia as well as vitamin deficiency anemia, which affects your nervous system. Calcium and magnesium deficiencies lead to osteoporosis.
Undigested food in your GI tract causes a range of uncomfortable GI symptoms in the short term and leads to more serious problems in the long term. For example, undigested food left to ferment in your GI tract can lead to gut bacteria overgrowth in your small intestine (SIBO). Low stomach acid also leaves you vulnerable to overgrowth of other common bacteria, including H. pylori, which is associated with chronic gastritis and peptic ulcer disease.
The most significant causes include:
Immediate symptoms involve indigestion, including:
Prolonged hypochlorhydria may produce symptoms of nutritional deficiencies, including:
Other contributing causes may include:
The symptoms of hypochlorhydria — symptoms of indigestion, nutritional deficiencies and possibly bacterial infection — can be caused by many things. Hypochlorhydria is only one possible cause. If you have several of the risk factors associated with low stomach acid, you might suspect that is your problem. But there’s no way to know for sure without taking a stomach acid test.
Healthcare providers use a variety of tests to diagnose hypochlorhydria. There are also some DIY tests you can try at home. These may not be as accurate, but they offer a relatively simple and inexpensive way of exploring your theory. We recommend that if you do get a positive result from an at-home test, you follow up with a trained healthcare provider.
The theory behind this at-home is that baking soda combined with stomach acid produces carbon dioxide (C02), which will cause you to burp. For the test, you’ll drink half a glass (4 ounces) of cold water combined with a quarter teaspoon of baking soda, on an empty stomach. Then time how long it takes you to burp. If it takes longer than three to five minutes, the theory goes, you don’t have enough stomach acid.
Your healthcare provider will conduct a physical exam and listen to your symptoms and health history. If they suspect hypochlorhydria, they will suggest one of several stomach acid tests.
If you test positive for hypochlorhydria, your healthcare provider may want to follow up with additional tests to detect nutritional deficiencies or bacterial infections. They’ll use all of this information to design your treatment plan.
Treating hypochlorhydria is a three-pronged process.
This condition can often be reversed, or at least successfully treated, with HCI supplements. It’s important to address the underlying causes, however. If you have an infection, disorder or inflammatory condition, these will continue to cause problems, including hypochlorhydria and others. Make sure to get a thorough medical screening before treating with HCI supplements. Your healthcare provider can help ensure you’re treating the causes and effects of hypochlorhydria, including specific nutritional deficiencies.
Diet alone won’t restore your stomach acid, but these guidelines may help improve your digestion while living with hypochlorhydria:
A note from Cleveland Clinic
Hypochlorhydria, or low stomach acid, is a relatively underdiagnosed condition that may be more common than we know. Symptoms commonly associated with hyperchlorhydria, or high stomach acid, including heartburn and reflux, may actually stem from hypochlorhydria. Medications to treat high stomach acid can contribute to low stomach acid, making digestive problems worse. Successful treatment requires careful diagnosis and testing. Medical tests can identify high or low stomach acid as well as other important factors that may be contributing to your symptoms. With the right information, your healthcare provider can help you make a plan to treat the causes and effects of hypochlorhydria.
Last reviewed by a Cleveland Clinic medical professional on 06/27/2022.
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