Dental enamel is the hardest and most highly mineralized substance in the body. The enamel structure is a crystalline latticework composed of myriad minerals, predominantly hydroxyapatite. Demineralization occurs when mineral ions are compromised and removed from dental enamel. The process progresses due to low pH in the saliva and when the oral environment is deprived of minerals in relation to the tooth’s overall mineral content. The hydroxyapatite latticework is subsequently softened by acids that are produced by the cellular action of plaque bacteria in the presence of dietary carbohydrates and sugars.
Demineralization of dental enamel is reversible, provided that the acidogenic properties of plaque biofilm are neutralized. The buffering capability of saliva plays a critical role in helping to restore a neutral pH in the oral cavity and at the tooth surface. Saliva encompasses a supersaturated solution of calcium and phosphate, which neutralizes acids. Remineralization of dental enamel occurs when dietary carbohydrates are removed and the pH of the plaque biofilm is raised to approximately 7.0.1 When the pH returns to a neutral point, the demineralization process is halted and the remineralization process begins to occur at the tooth surface. The process enables minerals to be deposited back into the areas of compromised enamel crystallites.
COMPOSITION OF SPORTS AND ENERGY DRINKS
Athletes are prone to dehydration and subsequently a diminished salivary flow. As a result, the oral cavity becomes an ideal environment for demineralization of enamel (Figure 1).2 The bacteria in biofilm are more potent without the buffering effect that saliva provides, and they are able to produce an acidic environment more readily.
Sports and energy drinks are typically consumed prior to and during sporting activities in order to reduce the adverse effects of dehydration on cardiovascular dynamics, temperature regulation, and exercise performance.3 Sports drinks were originally created as carbohydrate and electrolyte aqueous formulations to supplement performance and to prevent dehydration during strenuous exercise. Energy drinks originated in Japan during the 1950s and initially contained amphetamines until these drugs became illegal.4 The production and sale of sports and energy drinks are profitable and competitive industries, as demonstrated by the rapidly growing selection of products. The worldwide demand for sports drinks is impressive. The United States market alone is estimated to be worth more than $1.5 billion annually.5
Even though many types of sports and energy drinks are available, there is usually little difference in their composition.3 The main carbohydrates used in sports and energy drinks are glucose, fructose, sucrose, and synthetic polymers maltodextrins, also known as glucose polymers. The use of glucose polymers in sports drinks has increased in recent years, as they allow for the provision of more carbohydrates without increasing the concentration of the solution.5
Small amounts of electrolytes—generally sodium, potassium, and chloride—are added to sports and energy drinks to improve taste and to theoretically help maintain fluid/electrolyte balance. The addition of electrolytes affects beverage concentration, which in turn, influences the rate of absorption of the fluid and its contents.5 Although sports and energy drinks have been manufactured for individuals involved in sports and physical activity, they are widely used by the general population in preference to carbonated beverages.5
Sports and energy drinks have a low pH and contain sugars, creating a susceptible environment in the oral cavity for enamel demineralization. Most sports and energy drinks have a pH in the acidic range with a pH of 2 to 4 (Table 1)2,6,7 and a high titratable acidity level. Titratable acidity is a measurement of the acid concentration and consequently how easy or difficult it is to neutralize the acid. The more concentrated the acid is, the more erosive. Citric acid is frequently included in sports and energy drinks and has been found to be highly erosive, because its demineralizing effect on the enamel continues even after the pH has been neutralized.8
Many factors can modify the effect of sports and energy drinks on dental enamel. These include the chemical properties of the beverage ingredients being consumed, the frequency and method of contact between the enamel surface and the solution, salivary composition, buffering capacity, flow rate, pellicle formation, enamel type, host response, and the individual’s drinking habits and oral hygiene.
THE ROLE OF ORAL HEALTH PROFESSIONALS
Research shows that almost one in four adults in the US consumes sports and energy drinks at least once per week, and about one in nine do so at least three times per week over the course of a month.11 Sports and energy drinks have become a staple in the dietary habits of many; however, consumers are often unaware of the negative impact on dental enamel. Consequently, a research study examined the probability of demineralization of dental enamel by adding small amounts of hydroxyapatite to sports drinks. The results showed that the pH levels improved with increasing nano-hydroxyapatite concentration in the drinks, whereas the titratable acidity decreased.12 Therefore, demineralization was effectively prevented with the addition of nano-hydroxyapatite. A sports drink containing 0.25% nano-hydroxyapatite may prevent demineralization of dental enamel.12 Additionally, research revealed that the pH of test solutions increased and the titratable acidity decreased with the addition of casein phosphopeptide-stabilized amorphous calcium phosphate (CPP-ACP) to sports drinks. Adding CPP-ACP to sports drinks significantly reduced the beverage’s erosive effects without affecting the product’s taste.13 The results reported in these research studies are promising; however, further research is needed.
Due to their popularity, oral health professionals should discuss sports and energy drink consumption during their comprehensive evaluation and patient education practices. This is especially true for children and adolescents with a vulnerable mixed dentition who may be unaware of the possible demineralization properties of sports and energy drinks.
The addition of fluoride mouthrinses into oral hygiene regimens will help to remineralize the susceptible areas in dental enamel. Using products containing calcium phosphate technologies may also support remineralization. Rinsing with water after consuming sports or energy drinks may assist in neutralizing the acidogenic properties of the drink, thereby decreasing the likelihood of demineralization. Additionally, sports and energy drinks should be consumed at once instead of sipping throughout the day.
The acidogenic nature of sports and energy drinks can be a significant etiological factor in the demineralization of dental enamel. Sports and energy drinks are designed to prevent dehydration and replenish energy, but they also play a critical role in the demineralization of dental enamel. Oral health professionals should be aware of the ingredients in these drinks and their effects on dental enamel. Reinforcing proper oral hygiene and educating patients about the risks regarding the consumption of sports and energy drinks are essential to preventing demineralization of dental enamel and promoting oral health.
- Roberts M, Wright T. The dynamic process of demineralization and remineralization. Dimensions of Dental Hygiene. 2009;7(7):16-21.
- Pacak DK, Munoz HE. The downside of sports and energy drinks. Dimensions of Dental Hygiene 2012;10(10):45–49.
- Owen M, Mallette J, Phebus J. Effects of carbonated cola beverages, sports and energy drinks and orange juice on primary and permanent enamel dissolution. Austin Journal of Dentistry. 2014;1(1):1004.
- Enger D. Who made that energy drink? New York Times Magazine. December 6, 2013.
- Coombes JS. Sports drinks and dental erosion. Am J Dent. 2005;18:101–104.
- Klimis-Zacas D. A guide to the best and worst drinks. In: Consumer Reports on Health. Dubuque, Iowa: McGraw-Hill; 2008:13–18.
- Nix S. Williams’ Basic Nutrition and Diet Therapy. St. Louis: Elsevier; 2005:A8.
- Järvinen V, Rytömaa I, Heinonen O. Risk factors in dental erosion. J Dent Rese. 1991;70:942–947.
- Pinto S, Bandeca M, Silva C, Cavassim R, Borges A, Sampaio J. Erosive potential of energy drinks on the dentine surface. BMC Res Notes. 2013;6:67.
- Bartlett D, Coward P, Nikkah C, Wilson R. The prevalence of tooth wear in a cluster sample of adolescent schoolchildren and its relationship with potential explanatory factors. Br Dent J. 1998;184:125–129.
- Park S, Onufrak S, Blanck H, Sherry B. Characteristics associated with consumption of sports and energy drink among US adults: National Health Interview Survey, 2010. J Acad Nutr Diet. 2014;113: 112–119.
- Min J, Kwon H, Kim B. The addition of nano-sized hydroxyapatite to a sports drink to inhibit dental erosion—in vitro study using bovine enamel. J Dent. 2011; 39:629–635.
- Ramalingam L, Messer L, Reynolds E. Adding casein phosphopeptide-amorphous calcium phosphate to sports drinks to eliminate in vitro erosion. Pediatr Dent. 2005;27:61–67.
From Dimensions of Dental Hygiene. May 2017;15(5):18-20.