Baking soda is generally safe to drink in small amounts for short periods, but it carries real risks if you use too much or too often. A single teaspoon contains about 1,259 mg of sodium, which is more than half the daily recommended limit for most adults. That sodium load alone makes it something to approach carefully, and the potential complications go well beyond salt intake.
How Baking Soda Works in Your Stomach
When baking soda (sodium bicarbonate) hits your stomach, it reacts with hydrochloric acid to produce salt, water, and carbon dioxide gas. This reaction raises the pH of your stomach, which is why people reach for it as a quick heartburn remedy. The relief can be fast, often within minutes.
The carbon dioxide produced is what causes the intense burping that follows. Any bicarbonate that doesn’t react with stomach acid passes into the small intestine, gets absorbed into the bloodstream, and is eventually filtered out by the kidneys. The CO2 is expelled through your lungs. Your body has efficient systems for clearing small amounts, but those systems can be overwhelmed if you take too much.
What a Safe Amount Looks Like
For occasional heartburn, the typical dose is half a teaspoon dissolved in at least 4 ounces of water. It’s sold over the counter as an antacid, and it’s recognized as safe for that purpose at appropriate doses. But “available without a prescription” doesn’t mean “use freely.” You should take it at least two hours apart from any other medications, because it can change how your body absorbs them.
Baking soda is not a long-term solution for acid reflux or indigestion. If you find yourself reaching for it regularly over more than a couple of weeks, that’s a sign something else is going on. Children under six should not take it unless directed by a doctor, because their symptoms can easily mask a condition that needs different treatment.
The Sodium Problem
One teaspoon of baking soda delivers roughly 1,259 mg of sodium. The American Heart Association recommends no more than 2,300 mg per day, with an ideal limit of 1,500 mg for most adults. So a single teaspoon of baking soda, before you eat anything else that day, already puts you past the halfway mark.
For anyone with high blood pressure, heart disease, kidney disease, or liver disease, this is a serious concern. Sodium bicarbonate causes the body to retain water, which can worsen swelling in the legs and feet, raise blood pressure, and strain the heart and kidneys. Even people without these conditions can feel bloated and uncomfortable from the sodium and water retention.
What Happens if You Take Too Much
Overdoing baking soda can push your blood pH too high, a condition called metabolic alkalosis. In one documented case, a patient developed a dangerously elevated blood pH of 7.61 (normal is 7.31 to 7.41), along with critically low potassium levels and acute kidney injury. This wasn’t from a massive one-time dose. Chronic misuse can cause the same problems gradually.
Early symptoms of metabolic alkalosis include nausea, muscle twitching, tingling in the hands and feet, and confusion. More severe cases have involved seizures, loss of consciousness, and even brain hemorrhage from dangerously high sodium levels. These are rare outcomes, but they happen to real people who didn’t realize how much they were taking.
The Gastric Rupture Risk
The carbon dioxide gas produced by the reaction can be dangerous if your stomach is already full. Case reports describe gastric rupture, a tear in the stomach wall, after people took baking soda following a large meal. Two conditions create this risk: sudden distension of the stomach that thins and stretches the wall, combined with something preventing the stomach from emptying or venting the pressure. A big meal followed by a dose of baking soda can create exactly that combination. This is rare, but it’s one reason you should never take baking soda on an overly full stomach.
Who Should Avoid It Entirely
Baking soda is not safe for everyone, even in small doses. People with the following conditions should avoid drinking it:
- High blood pressure or heart disease: the sodium load can worsen both conditions
- Kidney disease: the kidneys are responsible for clearing excess bicarbonate, and impaired kidneys may not keep up
- Liver disease or edema: water retention can become dangerous
- Intestinal bleeding or appendicitis: baking soda can make both worse
If you take prescription medications, the timing matters. Baking soda can interfere with how your body absorbs a wide range of drugs. Keep at least a two-hour gap between baking soda and any other medication.
Legitimate Medical Uses
Despite the risks, sodium bicarbonate has real clinical value in specific situations. For people with chronic kidney disease (CKD), metabolic acidosis, where the blood becomes too acidic, is a common complication. Clinical guidelines from organizations including the Kidney Disease Improving Global Outcomes group recommend sodium bicarbonate supplementation for CKD patients whose bicarbonate levels fall below 22 mEq/L. A meta-analysis of 778 patients found that this treatment slowed the rate of kidney function decline and improved vascular health. This is a supervised medical treatment, not a home remedy.
Athletes also use sodium bicarbonate for performance. Known as “bicarb loading,” the practice involves doses of 0.2 to 0.5 grams per kilogram of body weight, sometimes spread over several days before competition. Research from the International Society of Sports Nutrition found it improves performance in high-intensity activities like cycling, rowing, swimming, and combat sports. For a 70 kg (154 lb) person, that’s 14 to 35 grams, a dose that frequently causes significant gastrointestinal distress and should only be attempted with careful planning.
The Bottom Line on Occasional Use
A half teaspoon of baking soda in water for occasional heartburn is unlikely to harm a healthy adult. The problems start when people use it daily, take too much at once, have underlying health conditions that make sodium dangerous, or combine it with a full stomach. It’s a potent chemical reaction happening inside your body, not a gentle home remedy, and treating it casually is where people get into trouble.