Dietitian Laura Tilt is standing outside smiling

Fact v Fiction: The Baking Soda Test

Welcome to the first in our new series, where our experts separate the fact from fiction around some popular gut health trends.

First up, the baking soda burp test. The DIY test that claims to be able to detect low stomach acid levels that’s been circulating on TikTok. But is it legit? We asked Registered Dietitian Laura Tilt to find out.

What is stomach acid and why is it important?

Glands lining your stomach produce around 1.5 litres of hydrochloric acid (stomach acid) a day. This acid is important because it kills microbes that could make you sick, and it also activates digestive enzymes which break down proteins and fats.

Now if your stomach doesn't produce enough acid, it can cause problems digesting food leading to symptoms like bloating, nausea and discomfort after eating. Over the longer term it can also lead to nutritional deficiencies.

What is the baking soda test?

The baking soda test involves mixing a quarter teaspoon of baking soda with 100-150ml of cold water, which you drink on an empty stomach.

When you drink the solution the baking soda reacts with your stomach acid to produce carbon dioxide which may cause you to burp. The theory is that if it takes longer than 3-5 minutes to burp you’ve got low stomach acid. But is it true?

When determining whether a test is accurate, we have to compare it to a ‘gold standard’ test. This is something which we know IS reliable and which accurately diagnoses a condition. In this case it's the Heidelberg test. It involves swallowing a small capsule which passes through the body in a few hours and accurately measures acidity levels in the stomach.

Now the baking soda test has never been compared to a gold standard test. There’s no research to prove that it works, there’s no agreed upon methodology and there are even differences in opinion on how long you should wait for a burp.

So, the baking soda test, Fact v Fiction?

It’s fiction. If you use the baking soda test you might end up misdiagnosing yourself and not getting the right treatment for your symptoms. If you do have symptoms for low stomach acid, book an appointment to see your doctor. These symptoms could be down to lots of different conditions, not just low stomach acid. If your doctor thinks a test is necessary, they’ll set you up with an accurate and reliable one.

And as for baking soda, my advice is to harness its ability to generate carbon dioxide for baking cakes.