After a meal, particularly one containing acidic foods, it is recommended to wait 20 to 30 minutes before brushing your teeth to allow saliva to neutralize the oral pH and avoid mechanical wear on the temporarily softened enamel.

noli's read

This recommendation is based on very sound physiological and clinical foundations. When consuming food, oral acidity increases, causing superficial and transient demineralization of the enamel. In situ clinical studies, such as the one from the University of Zurich (2008), confirm that immediate mechanical brushing after acid exposure significantly increases enamel wear. For this reason, the American Dental Association (ADA) and the Mayo Clinic officially recommend waiting 30 to 60 minutes before brushing. However, a 2017 case-control study provides a nuance: this fragility is primarily critical after consuming very acidic foods (citrus fruits, vinegar, sodas), whereas for neutral meals, quick brushing poses fewer risks. While waiting for this delay, simply rinsing your mouth with water or chewing xylitol gum can stimulate saliva and accelerate the return to a balanced pH without scrubbing the enamel.

the sources

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