We usually link heartburn and upset stomach to soaring levels of stomach acid. But the truth is, many digestive complaints are the result of low stomach acid. And most people have no idea. Get to know this important part of your digestive system a little better so you can keep the juices flowing.
What does your stomach acid do?
“Stomach acid has a number of important jobs to play for digestion and overall health,” says Erica Zellner, MS, a health coach and certified nutrition specialist at Parsley Health in Los Angeles. This watery, digestive fluid (also known as hydrochloric acid) is one of the main solutions secreted by your stomach, and works to:
- Break proteins into digestible amino acids (a process known as proteolysis)
- Activate pepsin, the primary enzyme in your stomach
- Stimulate the pancreas to release enzymes that break down food
- Kill potentially harmful bacteria before it reaches our intestines
- Prevent food from backing up into the esophagus (a tube that connects the throat with the stomach)
It’s important to have healthy levels of stomach acid in your system so all these key processes can keep moving smoothly. If you come up short, your digestion will suffer, possibly leading to a number of unpleasant symptoms and even chronic conditions.
What are the symptoms of low stomach acid?
When your stomach acid levels get too low (a condition known as hypochlorhydria), you may notice a variety of symptoms—and not all of them are in your gut. These are some of the most common symptoms of low stomach acid to look out for:
- Acid reflux or heartburn
- Undigested food in the stool
- Nausea while taking supplements
- Nutrient deficiencies
- Hair loss or brittle fingernails, which can signal nutrient deficiency
What causes low stomach acid?
Low stomach acid can be traced back to a number of causes. “At Parsley Health, the top cause of low stomach acid that we see is stress, particularly this year,” says Zellner. It’s one reason low stomach acid can go easily undiagnosed—most doctors aren’t looking at our stress levels. When you’re stressed, your body shifts processes that aren’t critical for survival in the moment—like digestion—to the back burner, Zellner explains. If you’re chronically stressed, your normal digestion is constantly being interrupted, including inhibiting gastric acid secretion, shows research in the Proceedings of the National Academy of Sciences.
Some other common causes include:
- Age (acid levels decrease as we get older, according to one review)
- Long-term use of antacids and proton pump inhibitors (used to treat ulcers and acid reflux)
- H. pylori infections (a common cause of stomach ulcers)
What happens if your stomach acid is too low?
One of the most noticeable effects of low stomach acid is the way it messes with your ability to digest nutrients—especially protein.
Without enough stomach acid, your body can’t break proteins into digestible amino acids, Zellner says. This can create a protein deficiency, which then leads to a deficiency in vitamin B12, magnesium, and iron. When you don’t get enough of these nutrients, both mild and severe health issues can crop up.
Vitamin B12, for example, needs help from stomach acid to detach from the protein that carries it. If it doesn’t detach, it can’t bind with other substances that carry it through your intestinal wall and into your bloodstream, Zellner says.
Your body needs both B12 and iron for healthy red blood cells and if you’re extremely low in these nutrients, you may develop anemia, a condition that happens when you lack enough healthy red blood cells. You may feel weak and fatigued, experience constipation, and in more serious cases, numbness and tingling in the hands and feet.
Another common side effect of low stomach acid is heartburn. That slow, painful burn you feel in your chest happens when your stomach acid backflows into your esophagus.
Contrary to popular belief, heartburn isn’t usually caused by an acidic stomach. Instead, that burn is likely connected to GI symptoms caused by low stomach acid. As Mary Stratos, PA-C, a physician assistant at Parsley Health said previously, “Without enough of this helpful stomach acid to break down food, maldigested food gets into the GI tract and GI pathogens overgrow, perpetuating the problem.”
At healthy levels, stomach acid also has disinfecting properties, helping prevent harmful bacteria from invading the rest of your GI tract. This means that as your stomach acid levels dip, your risk of GI infections (ex. E. coli, salmonella, H. pylori) goes up, according to a review in the Journal of Food Protection.
If low stomach acid goes untreated, it can even lead to conditions like allergies, asthma, autoimmune disorders, and skin problems, including acne and psoriasis. “When hydrochloric acid levels are hampered, there is a trickle down effect in the GI tract, including leading to leaky gut, a condition in which tiny holes develop in the lining of the intestinal tract, or dysbiosis, an imbalance between the good and bad bacteria in your gut,” explains Zellner. These gastrointestinal issues can actually confuse your immune system, making you more susceptible to autoimmunity and skin issues, she says.
How do you know if you have low stomach acid?
If you recognize any of the symptoms of low stomach acid, you try an easy at-home test to gauge whether stomach acid is at play.
One gentle approach that Parsley Health coaches often recommend is known as a baking soda challenge. “[With this challenge], we are looking to see how long it takes for you to burp,” Zellner says.
Simply mix a ¼-teaspoon of regular ol’ baking soda with 4-6 ounces of water and drink on an empty stomach (like first thing in the morning). Start a timer as soon as you drink the baking soda water. “If you have sufficient levels of stomach acid, the baking soda will be converted into carbon dioxide gas, which should cause belching about three minutes after drinking,” Zellner explains.
If you haven’t belched within five minutes, stop the timer. You may have low stomach acid. It can be helpful to work with a health coach, like those at Parsley Health, while doing this so they can help you interpret your exact results and come up with a treatment plan that’s personalized to you.
How to treat low stomach acid
If you think you have low stomach acid, make an appointment with a doctor. Doctors at Parsley Health take an in-depth history of your health and symptoms and may test your stomach pH (or acidity) to confirm the diagnosis. They may also recommend other advanced testing to look for other digestive issues or nutrient deficiencies. From there, you can discuss treatment options.
Parsley doctors and coaches use a variety of approaches to get your stomach acid back to healthy levels. Each plan is personalized to the member, incorporating their health goals and preferences. These are just a few ways your care team may work with you to improve stomach acid.
1. Eat your (bitter) greens
“My favorite first step to treat low stomach acid is to use bitter foods and digestive bitters,” Zellner says. Bitter flavors excite the digestive system and alert the body that a complex food is being eaten. “It’s like an alarm clock for the digestive system,” Zellner says. When this “alarm clock” sounds, it signals the body to secrete stomach acid, digestive enzymes, and bile.
Try to incorporate more wild plants (spinach, kale, arugula, dandelion) into your diet, as many of these feature a rich, bitter flavor. You can also try digestive bitters. Digestive bitters are a liquid derived from bitter plants that you can take orally before meals to stimulate your digestive system, Zellner says.
2. Introduce some acid
Supplementing with raw apple cider vinegar—a food with acidic properties—may also improve acid levels in the stomach by lowering the pH, allowing for better digestion. “Try diluting a small amount of apple cider vinegar with water and drinking at least five minutes before meals,” Zellner says. Never drink undiluted apple cider vinegar, as it can damage the enamel on your teeth, she adds.
3. Cut down on processed foods
Cleaning up your diet is another great way to improve your stomach acid. Limit processed foods (like pizza, chips, and packaged meats) and sugars, as these can cause inflammation in your stomach, lower acid, and even trigger acid reflux, Zellner says. Meanwhile, a diet rich in fruits and vegetables may lower inflammation and boost stomach acid.
4. Chew slowly
Digestion begins with the salivary enzymes in your mouth, which start their work the moment you take a bite. “Chewing thoroughly allows enough contact time for these enzymes to start breaking down your food,” Zellner says. It also helps prime your body to make adequate stomach acid for the meal ahead, she adds.
5. Find calm
Digestive function and mental wellbeing are closely linked. Therefore, practicing stress management strategies can play a pivotal role in restoring your gut health. Tap your health coach for ideas on how to incorporate calming habits into your lifestyle.