7 low stomach acid symptoms you shouldn’t ignore

Heartburn, bloating, nausea—many people assume experiencing these digestive issues means there’s too much stomach acid. But for some, the real issue is the opposite. Low stomach acid, also known as hypochlorhydria, can quietly interfere with digestion and nutrient absorption, often masquerading as more familiar gut problems.

The stomach produces gastric juice—about 1.5 to 3.5 liters (or 6 to 14 cups) each day. This juice is a very acidic liquid, with a pH below 2, and contains a high amount of hydrochloric acid. Specialized cells in the stomach produce this acid, along with enzymes that help begin the digestion process.

Stomach acid plays a critical role in breaking down food, absorbing key vitamins and minerals, and protecting against harmful bacteria. When levels are too low, your digestive system can struggle.

Understanding low stomach acid symptoms can help you connect the dots and decide when it’s time to talk with a doctor.

What causes low stomach acid? Understanding hypochlorhydria

Before diving into symptoms, it helps to understand what causes low stomach acid in the first place. Several factors can reduce acid production over time, sometimes gradually enough that it’s easy to miss the beginning signs of hypochlorhydria.

1. Aging

Aging is one of the most common contributors. As we get older, stomach acid production naturally declines. This can make digestion slower and less efficient, especially for protein-rich foods that are harder for your body to digest.

2. Autoimmune atrophic gastritis (AAG)

An important cause of low stomach acid is a condition called autoimmune atrophic gastritis (AAG). This condition happens when the immune system mistakenly attacks the stomach, damaging the cells that produce stomach acid and help with digestion.

3. Infections

Helicobacter pylori (H. pylori) infection can damage the stomach lining and lower your body’s acid production. While autoimmune atrophic gastritis is caused by the immune system attacking stomach cells, H. pylori infection may sometimes occur at the same time or play a role in triggering stomach inflammation.

4. Medications

Certain medications can also play a role. Long-term use of acid-suppressing drugs, such as proton pump inhibitors or H2 blockers, can lower stomach acid levels. While these medications are helpful for many conditions, they work by altering the stomach’s ability to produce gastric acid and should only be used when advised by your doctor and care team.

5. Stress

Chronic stress can also be another factor in your gut health. When the body is in a constant fight-or-flight mode, digestion often takes a back seat. Stress can reduce signals from the brain that tell the stomach to produce acid during meals, but it’s not clear if stress is an exact cause of hypochlorhydria.

6. Surgery

Surgeries involving the stomach, most commonly weight loss or bariatric surgeries, are another important cause of low stomach acid. These surgeries can lead to nutrient deficiencies, including low zinc or B vitamins, which can lower acid production as well.

In many cases, what causes low stomach acid is a combination of factors rather than a single issue.

7 low stomach acid symptoms to know

Low stomach acid symptoms aren’t always obvious. In fact, they often look like signs of other digestive issues, which is why hypochlorhydria can go undiagnosed for years. Here are the most common signs of low stomach acid.

1. Bloating

One of the most common symptoms of low stomach acid is bloating, especially after meals. When food isn’t broken down properly, it can ferment in the stomach and intestines, leading to uncomfortable fullness and gas.

2. Belching

Frequent belching is another clue. While occasional burping is normal, persistent belching after eating may signal that digestion is stalled.

3. Acid reflux

Heartburn or gastroesophageal reflux (GERD) may seem surprising, but they can also be symptoms of low stomach acid. When acid levels are low, the lower esophageal sphincter may not close properly, allowing stomach contents to move upward and cause burning or discomfort.

4. Nausea

Nausea after meals, particularly after eating meat or heavier foods, is another sign. Protein requires adequate stomach acid for digestion, and low levels can make these foods harder to tolerate.

5. Nutrient deficiencies

Over time, low stomach acid symptoms can extend beyond the gut, leading to nutrient deficiencies. 

Stomach acid is essential for absorbing iron, calcium, magnesium and vitamin B12. 

Low levels can contribute to:

• Fatigue
• Weakness
• Brittle nails
• Hair thinning
• Neurologic and even psychiatric symptoms

6. Infections

People with hypochlorhydria may also experience frequent infections. Stomach acid acts as a barrier against pathogens, so reduced acid can make it easier for bacteria to survive in the GI tract and possibly spread to other parts of the body.

7. Skin concerns

Skin issues, such as acne or eczema, have also been linked to digestive imbalances, including low stomach acid. While not a direct cause, poor digestion and nutrient absorption can affect skin health over time. Because these symptoms overlap with many other conditions, it’s important to see a doctor if you have any concerns. But recognizing common patterns can help you have a more informed conversation with your provider.

How to fix low stomach acid

If you think you may have low stomach acid, the first step is to see your primary care physician. Because digestive issues can be difficult to pinpoint, your doctor can help rule out other causes of your symptoms and determine whether hypochlorhydria might be part of the picture.

Adjust your diet and approach to eating

Diet changes are often a starting point to improve low stomach acid, including:

• Eat slowly and chew thoroughly to support digestion by giving the stomach more time to produce acid.
• Try eating smaller, balanced meals, which are easier to digest than large portions.
• Include protein at meals, but it may help to choose easily digestible options, such as fish or eggs, if heavier meats cause discomfort.
• Consider bitter foods, like arugula or dandelion greens, which can help stimulate digestion for some people.

Manage stress and well-being

Managing stress is another key component of how to fix low stomach acid. Practices such as deep breathing before meals, regular physical activity or mindfulness techniques can help shift the body into a rest-and-digest state.

Consider supplements

In some cases, addressing nutrient deficiencies can also support stomach acid production. Zinc and B vitamins are particularly important, but supplementation should always be guided by a healthcare professional.

Your provider may recommend digestive aids, such as supplemental enzymes or betaine hydrochloride (HCL), to support digestion. Keep in mind that these should only be used under medical supervision, especially for people with a history of ulcers or gastritis.

Review medications

If medications are contributing to low stomach acid, your provider may review whether it’s a good idea to make any adjustments. Never stop or change prescribed medications without talking to your doctor first.

Address underlying conditions

Treating underlying infections or autoimmune conditions contributing to low stomach acid is also essential. When the root cause is addressed, stomach acid levels may improve over time.

When to seek help for low stomach acid symptoms

Occasional digestive discomfort is common, but persistent symptoms are a sign to look deeper. If gastrointestinal symptoms are affecting your quality of life, or you are experiencing unexplained weight loss, anemia or ongoing fatigue, it’s important to speak to your provider.

Digestion isn’t just about what you eat—it’s also about how your body processes nutrients. If you’re concerned about low stomach acid symptoms, talk to your doctor or find a digestive specialist near you.