GUIDE: Baking Soda — 7 Uses That Really Work

Combined mechanical and chemical effectiveness

Baking soda is a mild abrasive (Mohs hardness of about 2.5) that cleans without scratching delicate surfaces. When mixed with a little water to form a paste, it effectively scrubs burnt-on residue from the bottoms of pots, stained bathtub grout, stains on tile grout, and light limescale deposits. Its alkaline nature also dissolves light grease and acidic food residues.

Comparative studies of household products have confirmed that baking soda satisfactorily removes stains caused by iron oxide, tannins (tea, coffee), and cooking grease. It is particularly effective at slightly whitening plastic utensils that have yellowed from turmeric or tomato. On chrome or anodized aluminum surfaces, however, it may leave slight marks—test it on a small area first.

Combinations That Boost the Effect

The combination of baking soda and white vinegar produces a dramatic reaction (foam, bubbles), often touted as a “super cleaner.” In reality, the reaction neutralizes both compounds—the alkaline baking soda and the acetic acid in the vinegar—and primarily produces water and salt. The residual cleaning effect is limited. It’s better to use them separately: vinegar for its acidic properties (limescale, bacteria), and baking soda for its alkaline properties (grease, odors).

On the other hand, the combination of baking soda and hydrogen peroxide (3% solution) forms a more effective whitening cleaner for grout and porous surfaces, as documented in several studies on alternative disinfectants.

The baking soda and vinegar reaction is one of the biggest myths in eco-friendly cleaning. Seeing foam and bubbles gives the impression of a powerful reaction—but it’s exactly the opposite: the two active ingredients neutralize each other. A little basic chemistry would go a long way toward changing many household cleaning practices.

Why Baking Soda Neutralizes Odors

Unpleasant body odors—from the armpits and feet—are caused by the bacterial breakdown of organic compounds in sweat. These malodorous compounds (isovaleric acid, mercaptans) are mostly acidic or sulfur-based. Baking soda, being an alkali, chemically neutralizes these molecules and stops the bacterial breakdown reaction by altering the local pH. It’s a simple and effective mechanism.

When applied directly to dry skin (in a very small amount, using the fingertips), it absorbs moisture and neutralizes odors for several hours. Natural deodorant formulations using bicarbonate as the main active ingredient are now available on the market and have been tested with positive results in independent studies on anti-odor effectiveness. It does not prevent sweating (it is not an antiperspirant), but it neutralizes the resulting odors.

Limitations: Risk of Irritation

Prolonged use of pure baking soda on the skin is associated with skin irritation in people with sensitive skin. Its alkaline pH (8.3) is far from the skin’s natural pH (4.5 to 5.5), and repeated application can weaken the skin barrier and cause contact dermatitis. Cases of significant irritation have been reported, particularly under the armpits where the skin is thin and subject to friction.

Practical recommendation: Use sparingly, not every day, and discontinue use if redness or irritation occurs. Commercial baking soda-based deodorants generally contain buffering agents that mitigate this risk. For sensitive skin, an alternative to pure baking soda (such as alum stone or essential oils) is preferable.

Baking soda works as a deodorant—but it is not harmless when used intensively on the skin. This illustrates once again that “natural” is not synonymous with “risk-free.” The amount used and the frequency of use matter just as much as the choice of product.

How Baking Soda Makes Dough Rise

This is its best-known and most universal use. Baking soda is a chemical leavening agent: when combined with an acidic ingredient (yogurt, lemon juice, vinegar, buttermilk, honey, unsweetened cocoa) and heat, it produces carbon dioxide (CO₂), which causes the dough to rise. This reaction is immediate and powerful—which is why dough containing baking soda must be baked quickly, unlike yeast, which acts slowly.

One teaspoon of baking soda (5 g) is equivalent to about 3 teaspoons of baking powder (which contains baking soda diluted with tartaric acid or phosphate). It’s the key ingredient in Irish soda bread, American pancakes, and quick muffins. It also gives the dough its characteristic golden color by promoting the Maillard reaction—the browning of sugars when heated.

Safe Use, Free of Myths

This is the safest and best-documented use of baking soda. The amounts used in cooking (half to one teaspoon per recipe) are safe for healthy adults, and the acidic ingredient in the recipe neutralizes much of the residual baking soda after baking. The U.S. FDA classifies sodium bicarbonate as “GRAS” (Generally Recognized As Safe) for food use.

The only caveat: pure baking soda cannot replace yeast in slow-rise breads, since it works through a chemical reaction rather than fermentation. And if the recipe doesn’t contain enough acidic ingredients, the soapy taste of the residual baking soda may come through—a classic mistake made by baking beginners.

Baking is probably the only field where the chemistry of baking soda is applied correctly by millions of people, often without their knowing it. There’s a certain beauty to it: precise molecular reactions, passed down through family recipes for generations.

Use 5: Odor neutralizer in refrigerators and trash cans

Placing an open bowl of baking soda in a refrigerator to absorb odors is a popular practice that has been partially validated. Baking soda absorbs acidic odors (fish, garlic, strong cheese) through chemical neutralization. A study by the University of Tennessee showed that a bowl of baking soda exposed to air does indeed reduce certain acidic odor molecules. However, its effectiveness is limited by space: the odor molecules must come into direct contact with the crystals. An open bowl in a large refrigerator will work best if placed in the center. It is recommended to replace it every 30 days.

For trash cans and compost bins, sprinkling baking soda directly on the bottom is significantly more effective than placing a bowl at a distance. Use 6 — Teeth whitening: Baking soda has been used in whitening toothpastes since the 1900s. Studies published in the Journal of Clinical Dentistry have shown that toothpastes containing baking soda remove surface stains (coffee, tea, tobacco) more effectively than toothpastes without baking soda, while being gentler on enamel than more aggressive abrasives. It can still be used occasionally in its pure powder form, but should be limited to once a week to avoid long-term enamel abrasion.

Use 7: Treating insect bites and mild itching

A baking soda paste applied to a bee, wasp, or mosquito bite can temporarily relieve itching. For bee and wasp stings (whose venom is slightly acidic), neutralization by alkaline baking soda mechanically reduces irritation. For mosquitoes (whose venom has a more neutral pH), the effect is less pronounced, but the coolness of the moist paste provides relief by constricting superficial blood vessels.

The Mayo Clinic lists this application as an acceptable first-aid treatment for mild skin irritations. It is not a substitute for antihistamine treatment in the event of an allergic reaction. In the event of signs of anaphylaxis (generalized swelling, difficulty breathing), only epinephrine and emergency medical care are appropriate.

These three uses illustrate a simple reality: baking soda works where acids are involved—acidic odors, acid stains, and acidic venom. That is its strength. And it is also its limitation: where alkalis, complex fats, or resistant biological agents are involved, it will be largely ineffective. Knowing its strengths helps avoid disappointment.

What Really Works

Among the dozens of uses attributed to baking soda, these seven are backed by solid evidence: occasional antacid, mild household abrasive, body deodorant (with precautions), leavening agent, odor neutralizer, mild teeth whitener, and relief from minor insect bites. In each of these cases, the mechanism of action is understood and the effectiveness is measurable. It’s not magic—it’s basic chemistry applied intelligently.

What Doesn’t Work

Baking soda does not cure cancer (this dangerous claim circulates online and is categorically refuted by all oncology institutions). It does not detoxify the liver. It does not alkalize the blood in a lasting way (the body precisely regulates its blood pH, between 7.35 and 7.45, regardless of diet). It is not a substitute for antibiotics or medical treatments. Using it as a substitute for necessary medical treatment can have serious consequences. For any persistent symptoms, a medical consultation remains essential.

Signed, Maxime Marquette, columnist