In a Japanese study*, it was announced that alkaline ion water can prevent dental erosion caused by acidic beverages. The human body is typically maintained in a slightly alkaline state, with a pH ranging from 7.35 to 7.45. However, it can shift towards being more acidic or alkaline depending on the pH of the foods and beverages consumed. The pH in our mouths is maintained at an average of 6.8 to 7.0 (slightly acidic, close to neutral) thanks to saliva. However, when food and beverages enter the mouth, the pH in the oral cavity tends to become acidic. When the pH of the enamel surface drops below pH 5.5, minerals like calcium and phosphate start to dissolve. According to this study, it was confirmed that “the oral cavity pH, which had been lowered by the intake of cola or sports drinks, was rapidly restored by the intake of alkaline ion water*.”
Dental erosion has garnered attention as a dental condition
The outermost layer of teeth, enamel, is composed of hydroxyapatite, making it the hardest tissue in the human body. However, when exposed to strong acids, it undergoes a chemical reaction, leading to its dissolution. As enamel dissolves, the underlying, softer dentin becomes exposed. This can result in gradual wear due to friction from chewing and teeth brushing.
Neglecting this condition can lead to various issues, including tooth sensitivity to cold and rapid progression of tooth decay. This phenomenon is known as “dental erosion,” and the pathological condition in which teeth are severely affected by erosion is referred to as “dental erosion syndrome” or “tooth erosion syndrome.”
The oral cavity PH
The pH in the oral cavity typically ranges from 6.8 to 7.0, indicating a neutral state. However, when we consume food and drinks, as well as when acids are produced by oral bacteria, the oral environment becomes more acidic. This increased acidity poses a higher risk for the progression of tooth decay. When the pH drops below pH 5.5, the demineralization process begins, where the enamel surface of the teeth starts to dissolve. The pH buffering capacity of saliva helps to maintain a stable environment. When the oral environment becomes acidic, saliva’s buffering capacity works to restore it to a neutral state. Keeping the pH in the oral cavity as close to neutral as possible throughout the day and ensuring that saliva’s buffering capacity functions effectively can help reduce the risk of tooth decay.
Demineralization and Remineralization
In our oral cavity, a constant cycle of “demineralization” and “remineralization” takes place to maintain the health of our teeth. Demineralization is the process by which acids produced by cavity-causing bacteria lead to the dissolution of calcium and phosphate from the enamel surface of the teeth. Remineralization, on the other hand, involves the uptake of calcium and phosphate, previously lost through demineralization, by the teeth through saliva, effectively restoring the tooth’s structure. As long as demineralization and remineralization occur at a balanced rate, healthy teeth are maintained.
Maintaining an oral pH as close to neutral as possible
Dental plaque produced by bacteria is sticky and adheres firmly to the teeth’s surface, making it difficult to remove with just rinsing. To prevent the formation of dental plaque, it’s crucial not to leave food debris and other substances that serve as bacteria’s food in the mouth after eating. The optimal frequency for daily teeth brushing is after every meal. This not only includes the three main meals (breakfast, lunch, and dinner) but also involves brushing your teeth whenever you consume substances that can act as a food source for bacteria, such as snacks or late-night snacks. Maintaining an oral pH as close to neutral as possible throughout the day and ensuring the efficient operation of saliva’s buffering capacity can help mitigate the chances of developing teeth decay.
According to “Establishment of risk assessment method for teeth erosion by acidic beverage, and examination of enamel remineralization promotion effect of alkaline ionized water,*” using a continuous pH measurement system with an intraoral pH antimony electrode, it was possible to measure the pH of the enamel surface. With the pH measurement system, they found the resting pH of the enamel surface was 5.9 (median), which was lower than the pH of saliva (6.9). According to their test, after consuming an acidic beverage (Sprite, pH 2.8), the enamel pH decreased below the critical pH, below pH 5.5, for demineralization and then returned to the pre-consumption level. Due to this test, Sprite was found to demineralize enamel. However, Alkaline Ion Water demonstrated the potential to promote remineralization of enamel demineralized by Sprite.
Nutrients. 2021 Oct; 13(10): 3440.
Published online 2021 Sep 28. doi: 10.3390/nu13103440
