The combination of hydrochloric acid, lipase, and pepsin combine to create the acidic gastric juices found in the stomach. These healthy stomach acid levels serve as a first line of defense for the gastrointestinal system, preventing infectious agents from reaching the intestines. A normal gastric pH is considered to be present with pH values >3, with values below 4 capable of killing bacterial invaders within 15 minutes. Gastric juices with a pH >3 mark the beginning stages of hypochlorhydria. As the pH increases above 4, there is an increased prevalence of bacterial overgrowth. Achlorhydria is defined as a pH >7.

Betaine HCL

Click here to learn more about the Hedberg Institute Membership.

There are two main categories of hypochlorhydria: iatrogenic and acquired. Iatrogenic hypochlorhydria is the most common, resulting from the use of medications to reduce gastric acid secretions. Proton pump inhibitors (PPIs) are one of the top ten most prescribed drugs in the world, contributing to the rise in iatrogenic hypochlorhydria. Malnutrition is the leading cause of acquired hypochlorhydria.

Individuals taking PPIs generally have a pH between 5-7. Individuals with hypochlorhydria are at an increased risk for infection and disease due to a loss of this protective barrier. Research conducted by Martinsen, Fossmark, and Waldum (2019) demonstrated that individuals with hypochlorhydria were at an increased risk of a variety of infections including bacterial, fungal, and parasitic infections. One study they reviewed reported a significant decrease in Shannon’s diversity of the GI microbiome and changes in 20% of the bacterial taxa in PPI users versus non-users.

The increased use of PPIs makes it necessary to review current medications, both prescribed and over the counter, at each patient encounter. Nutritional status should also be evaluated utilizing blood labs, anthropometrics, diet diaries, food allergies/sensitivities, etc. Other useful factors in screening a patient for gastric hypoacidity include assessing gender, age, stress levels/eating behaviors, geographic origin/nationality, testing of stomach acid levels, and labs to rule out concurrent diseases such as Helicobacter pylori, chronic gastritis, parietal cell autoantibodies, hypothyroidism, etc. Keep in mind that there can be discrepancies between different testing methods and cutoff values depending on the labs used.

Malnutrition can be the cause of or the result of hypochlorhydria. Malnutrition that leads to a deficiency in the nutrients needed to make HCL can cause hypochlorhydria. These include chloride, sodium, potassium, zinc, and iodine. Malnutrition can also develop as a result of hypochlorhydria. Decreased gastric acidity impairs nutrient absorption resulting in possible nutrient deficiencies for most of the essential vitamins and minerals including protein, iron, calcium, magnesium, zinc, vitamins A and E, copper, and all of the B vitamins. The presence of both malnutrition and hypochlorhydria increases the risk of enteric infections. There is also an increased prevalence of food allergies in individuals with reduced gastric acidity as they lose the ability to sufficiently denature proteins. With hypochlorhydria, larger protein peptides remain which can trigger an immune system response, resulting in allergic symptoms. Therefore, screening for hypochlorhydria should be conducted in individuals that suffer from malnutrition and/or food sensitivities/allergies.

There is also an increased prevalence of food allergies in individuals with reduced gastric acidity as they lose the ability to sufficiently denature proteins. With hypochlorhydria, larger protein peptides remain which can trigger an immune system response, resulting in allergic symptoms. Therefore, screening for hypochlorhydria should be conducted in individuals that suffer from malnutrition and/or food sensitivities/allergies.