Baking soda is a familiar household product often used as a traditional remedy for various health and hygiene purposes. Its history in oral care is long-standing, with many people using it as a simple, low-cost alternative to commercial toothpaste and mouthwash. We need to understand how this common substance interacts with the oral environment to determine its role in modern oral hygiene.
How Baking Soda Neutralizes Oral Bacteria
Sodium bicarbonate’s effectiveness in the mouth is primarily a matter of chemistry, focusing on its alkaline nature. Bacteria responsible for tooth decay thrive in an acidic environment, which they create by metabolizing sugars from food.
Baking soda acts as a powerful buffer, capable of rapidly neutralizing these bacterial acids and elevating the oral pH level. This shift creates an environment hostile to the growth and function of acid-loving bacteria, inhibiting their proliferation. While sodium bicarbonate is considered bacteriostatic—meaning it stops bacterial growth—it significantly disrupts the conditions required for decay-causing microbes to flourish. By quickly restoring a neutral pH, the mouth’s natural remineralization process is also supported.
Scientific Findings on Plaque and Gingivitis
Clinical studies have provided measurable evidence of sodium bicarbonate’s positive impact on common oral health issues. When incorporated into toothpaste, baking soda enhances the removal of plaque biofilm from tooth surfaces. The mild abrasive properties of sodium bicarbonate contribute to this mechanical removal of bacterial accumulations.
Research comparing fluoride toothpaste containing a substantial concentration of baking soda (e.g., 20% or 35%) to non-baking soda control toothpastes found significant improvements in oral health indices. One three-month clinical study showed that a 20% baking soda toothpaste reduced the Modified Gingival Index (MGI), Plaque Index (PI), and Gingival Bleeding Index (GBI) by 12.6%, 9.6%, and 44.2%, respectively, compared to the control.
A systematic review also confirmed that dentifrices containing baking soda were associated with better outcomes for plaque removal in single-use experiments. A six-month trial demonstrated that a 67% sodium bicarbonate toothpaste significantly improved gingival bleeding and plaque indices in participants with established gingivitis. The mechanical disruption of the sticky plaque biofilm, combined with the acid-neutralizing effect, reduces the localized inflammation that leads to gingivitis and bleeding. Furthermore, its ability to neutralize sulfur compounds that cause bad breath is a documented benefit stemming from its chemical buffering action.
Practical Use and Safety Considerations
For individuals interested in using sodium bicarbonate for oral hygiene, it can be utilized as a mouth rinse or as an additive to a toothbrushing routine. A common recommendation for a rinse is to dissolve about half a teaspoon of baking soda in half a glass of warm water. This solution can be swished for 30 to 60 seconds and then spit out, which is useful for neutralizing acid after consuming acidic foods or experiencing reflux.
When considering abrasiveness, pure baking soda is quite gentle, registering a Relative Dentin Abrasivity (RDA) value of approximately 7. This is extremely low compared to the typical adult toothpaste range of 35 to 250. This low abrasivity means that pure baking soda is unlikely to cause significant enamel wear or damage to exposed dentin, even with vigorous brushing. Commercial baking soda toothpastes, however, contain other ingredients that can increase their overall RDA value.
A safety consideration for high-volume or frequent use is the potential for increased sodium intake. A single teaspoon of baking soda contains over 1,000 milligrams of sodium. While a mouth rinse involves spitting out most of the solution, swallowing even small amounts repeatedly can contribute to a high-sodium diet. Individuals with specific health conditions, such as heart problems or kidney disease, or those following a low-sodium diet should consult a healthcare provider before making it a regular part of their routine. Additionally, while a baking soda paste is effective, it lacks the fluoride found in most commercial toothpastes, which is necessary to support the remineralization of enamel and prevent decay.