The sun is high in the sky; it's 110 degrees Fahrenheit in the shade and you've been working in the yard for hours. You come inside, take off your dusty, grimy gardening gloves, and open the fridge. Reaching for a can of your favorite soda, you flip open the lid, enjoying the sound of that unmistakable pop. Slowly, patiently, you pour the soda over a tall glass of ice, watching the bubbles rush to the surface. You lift the glass to your lips, anticipating the cool, invigorating relief your drink will bring as it begins to quench your thirst. But wait! Have you ever thought about what that ice cold beverage is doing to your teeth and gums? You might want to put down that glass.
Fizzy sodas are marketed as fun, refreshing beverages for beautiful, active people. But can frequent soda drinkers really expect to have gleaming white smiles like the ones we see in the ads, or is your beloved glass of bubbles doing more damage to your mouth than you think?
Most non-diet sodas contain the same basic combination of ingredients: carbonated water (which gives the soda its familiar fizz), sugar or corn syrup, artificial coloring, natural or artificial flavoring, and either phosphoric acid, citric acid or both. Diet sodas replace the sugars and corn syrups with an artificial sweetener such as aspartame or sucralose, but the other ingredients essentially remain the same.
So what is it about soda that makes it so bad for our teeth? And are sugar-free diet sodas any better than the regular variety? Read on before you take your next sip!
Tooth Decay from Soda
Your dentist will tell you (if she hasn't already!) that sodas have two major strikes against them: the sugar, which contributes to tooth decay and cavities, and the acids, which destroy the enamel on your teeth.
According to the Center for Science in the Public Interest, the average 12-ounce (340.2-gram) can of soda contains about 10 teaspoons (40 grams) of sugar. To put that amount into perspective, the USDA recommends that added sugars account for no more than 6 to 10 percent of our total calories. That means just one can of soda contains the maximum daily sugar allotment for someone who consumes 2,000 calories a day.
Diet soda drinkers: You're not off the hook. Diet sodas may be free of sugar, but they contain just as much acid as regular sodas. Phosphoric acid and citric acid, the two acids most commonly found in sodas, are added for their sharp, tangy flavors. Unfortunately, these ingredients also make sodas extremely bad for your teeth.
Acids weaken the teeth by dissolving and softening hard enamel, making teeth more prone to cavities, decay and sensitivity. The Minnesota Dental Association has found that exposure to acidic foods or beverages with pH values less than 4 can result in dental erosion. They also found that most sodas fall well below that threshold. Cola drinks were the most acidic, with pH levels ranging from around 2.5 (Coca-Cola and Pepsi) to 2.9 (Dr. Pepper). Several orange and lemon-lime soda drinks came in around the 3 mark. Root beer, which is often less carbonated than other sodas and less likely to contain citric and phosphoric acids, fared slightly better, with a pH above 4.
Fizzy sodas also contain carbonic acids, which are weak acids produced when the carbon dioxide gas that gives soda its distinctive bubbles dissolves in water. Even unflavored carbonated drinks like seltzer and club soda contain carbonic acids, making them slightly acidic, but nearly all the acidity in soda comes from citric or phosphoric acid, not the carbonation itself.
To be fair, non-carbonated beverages such as orange juice and lemonade can be just as sugary and acidic as sodas. But it's not often that you see someone leave a convenience store sipping from a giant 32-ounce (907.2 gram) cup of OJ. Popular sport drinks and energy drinks are also a concern, as they tend to be packed with sugar -- 5 to 12 teaspoons (25 to 59 grams) per serving, highly acidic (Gatorade has a pH of around 2.9, depending on the variety), and, unlike good old OJ, heavily consumed by teens and young adults. Even flavored waters (both sweetened and sugar free) can be fairly acidic, since they often contain citric acid in addition to the naturally occurring carbonic acids.
If soda can do this much harm to your teeth, what is it doing to the rest of your body? We thought you'd never ask.
What's soda doing to your mouth and body?
If there's any good news about the effect of soda on your teeth, it's that you can keep the damage in check by drinking soda only rarely and taking measures to protect your teeth any time you indulge in a serving of the fizzy stuff. Dentists recommend drinking soda only with a meal, since the food will help to absorb and dilute the acid, and using a straw to minimize the soda's contact with your teeth. Always brush your teeth as soon as possible after drinking soda, and if you can't brush right away, drink some water to help wash the sugar and acid away from your teeth.
Of course, once you've swallowed that sip of soda, you'll want to consider its effect on the rest of your body, too. The sugar and calories in regular soda are the most obvious concern, and with good reason. The Center for Science in the Public Interest says that carbonated soft drinks are the single biggest source of calories in the American diet, contributing to weight gain, obesity and Type II diabetes.
And public health officials worry, not only about what ingredients soda puts into our diets, but also what it pushes out. Kids who drink soda regularly drink less milk, water and fruit juice, and heavy soft drink consumption is associated with a lower intake of essential vitamins, minerals and dietary fiber.
A University of Minnesota study found that people who drink just two or more sugary sodas per week were nearly twice as likely to develop pancreatic cancer as non-soda drinkers. While the exact cause and effect are unclear, study participants who drank mostly fruit juice instead of soda did not have the same risk.
Many soda drinkers believe that switching to diet solves the problem. But just as the acid in diet sodas causes damage to your teeth, it can also have a negative effect on other parts of your body. The phosphoric acid in soda has been associated with lower bone density and an increased risk of osteoporosis because it interferes with the body's ability to absorb and use calcium. Both regular and diet sodas also frequently contain caffeine, as well as artificial colorings such as Yellow No. 5, which has been linked with attention deficit disorder in young children.
Your best bet? Put down that soda and pick up a glass of cold, refreshing water, right from the tap.
More Great Links
- Brown, Catriona J. et. al. "The erosive potential of flavoured sparkling water drinks." International Journal of Paediatric Dentistry. Volume 17, Issue 2. Pages 86-91. March 2007.
- Colgate Oral and Dental Health Research Center. "Soda or Pop? It's Teeth Trouble by Any Name." (Sept. 19, 2011) http://www.colgate.com/app/CP/US/EN/OC/Information/Articles/Oral-and-Dental-Health-Basics/Oral-Hygiene/Oral-Hygiene-Basics/article/Soda-or-Pop-Its-Teeth-Trouble-by-Any-Name.cvsp
- Fooducate Blog. "11 Quick Facts about Phosphoric Acid." June 30, 2009. (Sept. 25, 2011) http://blog.fooducate.com/2009/06/30/11-quick-facts-about-phosphoric-acid-yes-that-chemical-in-coca-cola/
- Jacobson, Michael F. "Liquid Candy: How Soft Drinks Are Harming Americans' Health." Center for Science in the Public Interest. 2005. (Sept. 23, 2011) http://www.cspinet.org/new/pdf/liquid_candy_final_w_new_supplement.pdf
- Loewen, Robin, D.D.S., et. al. "Pucker Up: The Effects of Sour Candy on Your Patients' Oral Health." Minnesota Dental Association. March-April 2008. (Sept. 23, 2011) http://www.mndental.org/newsletter_archive/2008_march_-_april/features_-_march-april_2008/pucker_up-the_effects_of_sour_candy_on_your_patients_oral_health/
- OralAnswers.com. "Nine Drinks That Can Dissolve Your Teeth." March 1, 2010. (Sept. 25, 2011) http://www.oralanswers.com/2010/03/nine-drinks-that-can-dissolve-your-teeth/
- Peterson, Dan. "Pop and Cavities: Cavities in a Can." DentalGentalCare.com. Feb. 6, 2008. (Sept. 25, 2011) http://www.dentalgentlecare.com/diet_soda.htm
- Po, Sarah. "Why Is Soda Bad for Your Teeth?" Dr. Sarah Po, Family & Cosmetic Dentistry. Jan. 19, 2010. (Sept. 25, 2011) http://www.elitesacramentodentist.com/soda-bad-teeth
- Reuters. "Study links sugary soft drinks to pancreas cancer." Feb. 8, 2010. (Sept. 25, 2011) http://www.reuters.com/article/2010/02/08/idUSN07113352
- Senese, Fred. "Why is phosphoric acid in soda pop?" General Chemistry Online. (Sept. 23, 2011) http://antoine.frostburg.edu/chem/senese/101/consumer/faq/why-phosphoric-acid-in-soda-pop.shtml
- Trimarchi, Maria. "How 2-Liter Dispensers Work."HowStuffWorks.com. April 28, 2009. (Sept. 23, 2011) https://electronics.howstuffworks.com/gadgets/kitchen/2-liter-dispensers.htm