Yes, baking soda is alkaline. Its chemical name is sodium bicarbonate, and when dissolved in water it produces a solution with a pH of roughly 8 to 8.5, placing it firmly on the basic (alkaline) side of the pH scale. That alkalinity is what makes it useful as an antacid, a leavening agent, and a cleaning product, but it also means it can cause problems when used carelessly.
How Alkaline Baking Soda Actually Is
The pH scale runs from 0 (strongly acidic) to 14 (strongly alkaline), with 7 being neutral. A typical baking soda solution lands around 8.3 to 8.6, depending on concentration. That makes it mildly alkaline, comparable to seawater or eggs. It is not a strong base like bleach (pH ~13) or lye, but it is basic enough to neutralize acids on contact.
When baking soda meets an acid, the bicarbonate ion grabs a hydrogen ion from the acid and forms carbonic acid, which immediately breaks down into water and carbon dioxide gas. That reaction is why a spoonful of baking soda fizzes in vinegar, why it makes dough rise when paired with buttermilk, and why it can relieve heartburn by neutralizing stomach acid.
Baking Soda vs. Baking Powder
Baking soda is pure sodium bicarbonate, 100% alkaline. Baking powder contains sodium bicarbonate too, but it also includes a dry acid (like cream of tartar) and a starch to keep the two from reacting prematurely. Because the acid and base are already packaged together, baking powder only needs a liquid to activate. Baking soda, on the other hand, needs you to supply the acid, whether that’s yogurt, lemon juice, brown sugar, or cocoa powder.
This distinction matters in cooking. If a recipe calls for baking soda and you skip the acidic ingredient, the alkaline sodium bicarbonate won’t fully react. You’ll taste a soapy, metallic flavor in the finished product.
Using Baking Soda as an Antacid
Because baking soda is alkaline, it has long been used to neutralize excess stomach acid. The Mayo Clinic lists a standard dose of half a teaspoon dissolved in a glass of water every two hours for adults. For the effervescent powder form, the dose ranges from 1 to 2.5 teaspoons in cold water after meals, with a daily maximum of about 5 teaspoons.
One teaspoon (roughly 5 grams) of baking soda contains about 59 milliequivalents of sodium bicarbonate. The FDA considers the safe daily ceiling to be 200 milliequivalents for adults under 60 and 100 milliequivalents for those over 60. That translates to roughly 3.5 teaspoons per day for younger adults and under 2 teaspoons for older adults.
What Happens if You Take Too Much
Swallowing large amounts of baking soda can push the blood’s pH too high, a condition called metabolic alkalosis. In one documented case, a patient consumed about 20 grams (roughly 4 teaspoons) in a single dose, exceeding the safe threshold and triggering serious symptoms. Those symptoms can include confusion, dizziness, muscle twitching, involuntary spasms, and in extreme cases, loss of consciousness or seizures. The large sodium load also raises blood pressure and causes fluid retention.
Occasional, measured use as an antacid is generally safe. The risk comes from treating baking soda like a harmless household substance and taking unmeasured, repeated doses.
Baking Soda and Kidney Disease
When kidneys lose function, they struggle to clear acid from the blood, and bicarbonate levels drop below the normal range of 22 to 29 milliequivalents per liter. Sodium bicarbonate supplements are one of the few options for correcting this imbalance. Kidney disease guidelines from KDIGO recommend aiming for normal serum bicarbonate levels when acidosis is confirmed and no reversible cause is found.
There is a trade-off, though. A typical regimen of 600 milligrams of sodium bicarbonate three times daily adds about 500 milligrams of sodium to the diet each day. For people already managing high blood pressure or fluid retention, that extra sodium can be a problem. Dosing in this context is individualized and based on bloodwork, not something to self-manage with a box from the pantry.
Athletic “Soda Loading”
Some athletes use baking soda before high-intensity exercise to buffer the acid that builds up in muscles during hard efforts. The idea is straightforward: raising bicarbonate levels in the blood helps shuttle hydrogen ions (the byproduct of intense exertion) out of working muscles, delaying the burning sensation that forces you to slow down.
The most commonly studied dose is 0.3 grams per kilogram of body weight, taken 60 to 90 minutes before exercise. For a 70-kilogram (154-pound) person, that works out to about 21 grams, or roughly 4 teaspoons. Research shows the approach can improve performance in efforts lasting roughly 1 to 7 minutes, like 400- to 1500-meter runs, rowing intervals, or repeated sprints. The biggest practical barrier is gastrointestinal distress: nausea, bloating, and cramping are common at effective doses.
Why It Can Irritate Your Skin
Viral beauty trends have promoted baking soda as a face scrub or acne treatment, but dermatologists consistently push back. Healthy skin maintains a slightly acidic pH of about 4.5 to 5.5. That acid mantle holds in moisture and keeps harmful bacteria in check. Baking soda’s pH of 8+ is far enough above the skin’s natural range to strip protective oils and disrupt the barrier.
The result, sometimes after a single application, can be dryness, flaking, redness, increased sensitivity, and even breakouts. Repeated use compounds the damage. The same alkalinity that makes baking soda effective at cutting grease on a stovetop makes it too harsh for facial skin.