Mixing baking soda into water is the simplest way to make alkaline water at home: stir roughly half a teaspoon (about 2-3 grams) of baking soda into an 8-ounce glass of water, and the pH rises from around 7 to somewhere between 8 and 9. The chemistry is straightforward, since baking soda (sodium bicarbonate) is a basic compound that dissolves readily and shifts the water’s pH upward almost instantly. But the more interesting questions are what that alkaline water does once you drink it, whether it offers real health benefits, and where the line sits between a harmless home remedy and a genuine safety risk.
The Recipe and How to Adjust It
The standard starting point is half a teaspoon of baking soda per eight ounces (about 240 mL) of water. That amount dissolves completely with a quick stir and produces a mildly alkaline solution, typically around pH 8.5. If you want a slightly higher pH, you can go up to a full teaspoon per glass, which pushes the water toward pH 9 or a bit above. Going beyond that doesn’t improve anything and starts to make the water taste distinctly soapy and unpleasant.
A few practical details matter. Use plain, room-temperature or cool water. Baking soda dissolves faster in warm water, but it works fine in cold water if you stir for 15-20 seconds. Make sure the box says “sodium bicarbonate” and nothing else; some baking powder products contain additional ingredients like cream of tartar or cornstarch that you don’t want. And because dissolved baking soda can gradually lose its potency once mixed, drink the water within an hour or two rather than making a pitcher to sip all day.
Each half teaspoon of baking soda contains roughly 630 milligrams of sodium. That’s a meaningful amount, about a quarter of the daily limit recommended for most adults. If you’re watching your sodium intake for blood pressure or heart health reasons, this is worth tracking carefully. Drinking multiple glasses a day adds up fast.
What Happens in Your Stomach
Your stomach is strongly acidic, with a resting pH somewhere between 1.5 and 3.5. When alkaline baking soda water arrives, the sodium bicarbonate reacts with hydrochloric acid almost immediately. That reaction produces carbon dioxide, water, and sodium chloride (table salt). You may notice this as a mild fizz or belch shortly after drinking. Research on this reaction has shown that even though the chemical reaction itself is nearly instantaneous, the carbon dioxide gas releases slowly because it initially dissolves in the surrounding liquid before gradually escaping into the gas phase.1PubMed. Gas production after reaction of sodium bicarbonate and hydrochloric acid
This means the stomach’s acidity doesn’t stay neutralized for long. Your stomach lining continuously secretes fresh acid, and within 30 to 60 minutes, the pH typically returns to its baseline. The body has a robust system for maintaining acid-base balance, and a glass of alkaline water is a small, temporary input into that system. Anyone claiming that drinking alkaline water permanently changes your body’s pH is misunderstanding basic physiology.
How Your Body Keeps Its pH Stable
Blood pH sits in an extremely narrow range, around 7.35 to 7.45, and your body defends that range aggressively. The kidneys are one of the primary tools for this job. They reabsorb bicarbonate from the fluid passing through them and generate new bicarbonate as needed to keep blood pH steady. Roughly 70 to 80 percent of filtered bicarbonate gets reclaimed in the earliest stretch of kidney filtering, with additional recovery happening further along the process.2PubMed Central. Kidney metabolism and acid–base control: back to the basics
When you drink baking soda water, any bicarbonate that survives the stomach and gets absorbed into the blood is handled by these same systems. If blood bicarbonate rises above normal, the kidneys simply excrete the excess. In a healthy person, a single glass of mildly alkaline water barely registers as a blip. This is why proponents of alkaline water sometimes overstate its effects: the body is designed to neutralize exactly this kind of input. The flip side is that for people whose kidneys aren’t working well, that safety net has holes, which is where the medical research becomes relevant.
Relief for Heartburn and Acid Indigestion
The most time-tested reason to drink baking soda in water is heartburn relief. Baking soda neutralizes stomach acid effectively and quickly. An in-vitro study comparing household remedies with a commercial antacid found that baking soda dissolved in water showed acid-neutralizing capacity on par with a standard liquid antacid product, and the effect of baking soda was essentially instant.3Journal of Drug Delivery and Therapeutics. In-vitro Gastric acid percent neutralizing potential of household remedies verses marketed antacid preparation: A case report
A randomized trial looking at bicarbonate-rich mineral water for heartburn found that about 85 percent of people drinking the bicarbonate water experienced meaningful relief, compared with roughly 64 percent on placebo. The bicarbonate group also saw improvements in quality-of-life measures related to food and drink problems, emotional distress, and energy levels, and they used less rescue antacid medication over six weeks.4PubMed Central. Heartburn relief with bicarbonate-rich mineral water: results of the randomised, placebo-controlled phase-III trial STOMACH STILL That trial used mineral water rather than homemade baking soda water, but the active ingredient doing the work is the same bicarbonate ion.
For occasional heartburn, half a teaspoon in water is a reasonable home remedy. But if you’re reaching for baking soda more than a couple of times a week, that’s a signal to see a doctor rather than continuing to self-treat. Chronic acid reflux can damage the esophagus, and masking the symptoms with baking soda doesn’t address the underlying cause.
The Safety Line Between a Little and Too Much
A single glass of baking soda water made with half a teaspoon is well tolerated by most healthy adults. The trouble starts when people use much more than that, use it too frequently, or combine it with other factors that shift the body’s acid-base balance.
Excessive baking soda ingestion can cause a condition called metabolic alkalosis, where the blood becomes too alkaline. Case reports describe patients arriving at emergency departments with a range of serious symptoms after overdoing baking soda. The clinical picture can include seizures, abnormal heart rhythms, and even cardiopulmonary arrest in extreme cases.5The Journal of Emergency Medicine. Severe metabolic alkalosis due to baking soda ingestion: case reports of two patients with unsuspected antacid overdose A case report reviewing the literature found that patients with severe metabolic alkalosis from baking soda misuse experienced altered mental states including confusion, agitation, and loss of consciousness. Neuromuscular symptoms like involuntary twitching, muscle spasms, and even seizure-like activity have also been documented.6PubMed Central. Metabolic alkalosis-an adverse effect of baking soda misuse: A case report and literature review
These cases almost always involve people consuming tablespoon-sized quantities rather than teaspoon-sized amounts, or using it many times daily over extended periods. But it’s worth understanding that baking soda is not benign just because it’s a common kitchen ingredient. The margin between a helpful dose and a harmful one is narrower than many people assume. General guidance from the product packaging itself usually suggests no more than seven half-teaspoon doses in a 24-hour period, and not for more than two weeks without medical advice.
Sodium, Blood Pressure, and the Salt Question
The biggest everyday concern for most people isn’t metabolic alkalosis but sodium. Baking soda is about 27 percent sodium by weight, so every half teaspoon delivers a significant sodium load. Conventional wisdom would suggest this should raise blood pressure, and for people already managing hypertension, that’s a legitimate worry.
Interestingly, a randomized controlled study that had participants drink sodium-and-bicarbonate-rich water found no significant difference in blood pressure changes compared with low-bicarbonate water, even among participants who already had high blood pressure. The additional sodium was effectively excreted in the urine, and urinary sodium excretion showed no statistical association with blood pressure increases in the high-bicarbonate group. The researchers also found that urinary calcium excretion actually decreased in the bicarbonate group.7PubMed. Blood Pressure Stability and Plasma Aldosterone Reduction: The Effects of a Sodium and Bicarbonate-Rich Water – A Randomized Controlled Intervention Study
That’s a single study, though, and it doesn’t overwrite decades of evidence linking high sodium intake to elevated blood pressure in salt-sensitive individuals. If your doctor has told you to limit sodium, adding baking soda to your daily water should be a conversation you have with them first, not something you start on your own based on one promising trial.
What the Research Says About Kidney Health
Sodium bicarbonate has been studied in people with chronic kidney disease, where the kidneys gradually lose the ability to regulate bicarbonate and acid on their own. A systematic review and meta-analysis found that oral sodium bicarbonate raised serum bicarbonate levels and slowed the decline in kidney filtration rate compared with control groups.8PubMed Central. The Effects of Oral Sodium Bicarbonate on Renal Function and Cardiovascular Risk in Patients with Chronic Kidney Disease: A Systematic Review and Meta-Analysis That sounds encouraging, but the picture gets more complicated with individual trials. A multicenter, placebo-controlled trial in people with stage 3 and 4 kidney disease found that while sodium bicarbonate did successfully raise blood bicarbonate levels, it did not produce a statistically significant difference in kidney filtration rate compared with placebo over two years of follow-up.9PubMed Central. Effects of Sodium Bicarbonate in CKD Stages 3 and 4: A Randomized, Placebo-Controlled, Multicenter Clinical Trial
A separate trial comparing sodium bicarbonate with sodium citrate in kidney disease patients found both substances raised serum bicarbonate by a similar amount, with no meaningful difference between the two approaches.10PubMed Central. Sodium citrate versus sodium bicarbonate for metabolic acidosis in patients with chronic kidney disease: A randomized controlled trial All of this is supervised medical therapy in patients with diagnosed conditions, using specific dosing regimens under monitoring. It is not evidence that healthy people should drink baking soda water to protect their kidneys.
There is also some data suggesting a relationship between bicarbonate levels and kidney stones. A retrospective study of patients with chronic kidney disease found that lower serum bicarbonate was associated with a higher risk of developing kidney stones. Each small drop in bicarbonate corresponded to a modestly increased hazard.11PubMed Central. Association of serum bicarbonate with the development of kidney stones in patients with chronic kidney disease: a retrospective cohort study In clinical practice, dilute sodium bicarbonate solutions are sometimes used as an adjunct therapy in kidney stone patients to alkalinize urine and reduce crystal formation, typically targeting a urinary pH of 6.5 to 7.0.12PubMed Central. Dietary baking soda (NaHCO3) therapy recovered urolithiasis-induced kidney injury in mice by inhibition of oxidative stress, pyroptosis, and inflammation through gut-kidney axis Again, this is a medical intervention guided by urine pH testing, not a DIY wellness practice.
Drug Interactions Worth Knowing About
If you take any regular medications, baking soda water isn’t as neutral as it seems. Because sodium bicarbonate raises the pH of your stomach contents, it can change how your body absorbs certain drugs. Raising gastric pH can increase the solubility and absorption of some medications that don’t dissolve well in acid, potentially leading to higher-than-expected drug levels in your blood.13PubMed. Enhancement of drug absorption by antacids. An unrecognised drug interaction
The interaction works in both directions depending on the drug. Some medications are designed to dissolve in an acidic stomach environment, and neutralizing that acid can reduce their absorption. Others dissolve better at higher pH and may be absorbed more rapidly or completely. This is particularly relevant for medications with narrow therapeutic windows, where small changes in blood levels can mean the difference between an effective dose and a toxic one. If you take prescription medications regularly, check with your pharmacist before making baking soda water a daily habit. The standard advice for any antacid applies here: separate it from other medications by at least two hours.
The Athletic Performance Angle
One area where sodium bicarbonate has been studied seriously is exercise performance. The idea is that during high-intensity exercise, muscles generate lactic acid and hydrogen ions that contribute to the burning sensation and fatigue you feel. Sodium bicarbonate in the bloodstream could theoretically buffer some of that acid, delaying the point at which performance falls off. This has been proposed as an ergogenic aid, and systematic reviews of the research have examined its effects across different exercise durations and intensities.14PubMed Central. The Impact of Sodium Bicarbonate on Performance in Response to Exercise Duration in Athletes: A Systematic Review
Athletes who use this approach typically take much larger doses than what goes into a glass of alkaline water, often in the range of 200-300 milligrams per kilogram of body weight. For a 70-kilogram person, that’s 14 to 21 grams, roughly four to six teaspoons consumed an hour or two before competition. At those doses, gastrointestinal distress is common and sometimes performance-limiting in itself, with nausea, bloating, and diarrhea being frequent complaints. The modest performance benefits seen in some studies apply mainly to short, high-intensity efforts lasting one to seven minutes, like a 400-meter sprint or a rowing ergometer test. Sipping a glass of mildly alkaline water before your morning jog isn’t going to do anything noticeable.
Oral Health and Baking Soda Rinses
Baking soda’s pH-shifting ability extends beyond the stomach. When used as a mouth rinse, it can raise salivary pH, which matters because the bacteria responsible for tooth decay thrive in acidic environments. A study measuring salivary pH changes found that rinsing with baking soda dissolved in water produced a significant increase in salivary pH, bringing it back to a neutral range.15American International Journal of Multidisciplinary Scientific Research. Evaluation of Salivary pH Changes with Probiotic, Baking Soda and Mineral Water Rinse Among Individuals with Low Caries Experience
This is actually a more evidence-supported use of baking soda water than drinking it. Swishing a mild baking soda solution after meals or after consuming acidic foods and drinks can help neutralize the oral environment and reduce the window of time during which tooth enamel is vulnerable to acid erosion. Many toothpaste formulations already include sodium bicarbonate for this reason. A rinse made from about a teaspoon of baking soda in a cup of warm water, swished for 30 seconds and spit out, is a simple practice that dentists have recommended for decades, particularly for patients undergoing chemotherapy or radiation therapy who develop painful mouth sores. Because the solution is spit out rather than swallowed, the sodium intake and digestive concerns largely disappear.
Who Should Skip Baking Soda Water Entirely
Some people should not drink baking soda water in any amount without explicit medical guidance:
- Children under five: Their smaller body weight means even half a teaspoon creates a proportionally large bicarbonate and sodium load. Accidental ingestion of baking soda by young children has led to emergency department visits.
- Pregnant women: The sodium load can contribute to fluid retention and elevated blood pressure, both of which are already concerns during pregnancy.
- People on sodium-restricted diets: If you’ve been told to keep sodium below a specific daily threshold, a single glass of baking soda water could consume a significant portion of your allowance.
- People taking potassium-sparing diuretics or ACE inhibitors: Bicarbonate loading can interact with medications that already affect electrolyte balance, potentially compounding effects on potassium levels.
- Anyone with kidney disease: As discussed earlier, bicarbonate supplementation in kidney disease is a medical decision based on lab values, not a home remedy. The kidneys’ reduced ability to excrete excess bicarbonate and sodium makes unsupervised use risky.
For everyone else, an occasional glass of baking soda water for heartburn or curiosity is unlikely to cause problems. The key word is occasional. Turning it into a daily multi-glass ritual based on wellness claims about alkaline water “detoxifying” or “oxygenating” your body pushes you into territory where the risks are real and the supposed benefits aren’t supported by evidence. Your body already regulates its pH with extraordinary precision, and a glass of slightly alkaline water doesn’t improve on that system. Where baking soda water genuinely helps, it helps for specific, limited reasons: neutralizing stomach acid in the moment, raising oral pH after an acidic meal, or serving as a medically supervised adjunct in kidney or stone management. Those are the claims the evidence actually supports.