By Melissa Breyer, Mother Nature Network
Toothpaste may be one of the more taken-for-granted products that we put in our mouths. It's not a food product so it gets less scrutiny than, say, Diet Coke and Twinkies. But if you brush your teeth two or three times a day, that's 730 to 1,095 times a year. Toothpaste isn't meant to be swallowed, but with that many brush-and-rinses annually, it's safe to assume that at least a smidge of toothpaste will go down the hatch. Probably not enough to worry about, but it's interesting to know what's going in our mouths.
Ancient toothpastes included ingredients such as ox hoof ashes, burnt eggshells, crushed bones, oyster shells, powdered charcoal and bark. Modern ingredients aren't quite as poetic. What are we using to keep our pearly whites their healthiest today? The following is a combined list of ingredients (many of them overlap between products) found in three leading toothpaste brands: Colgate Total Toothpaste, Fresh Stripe; Aquafresh All Tartar Control; and Crest 3D White Advanced Vivid Toothpaste. We've come a long way from the charred remains of cows' feet.
A polymer used for thickening and as an emulsion stabilizer.
Food-grade carrageenan is an extract of red seaweed (Chondrus crispus). It is used to thicken and stabilize a large array of food products, including frozen yogurt and reduced-fat ice cream. It's used as a thickening agent in toothpaste.
Carboxymethylcellulose sodium, also known as cellulose gum, is used as a thickener for creamy toothpastes.
A foaming ingredient derived from coconut oil, cocamidopropyl betaine helps to emulsify and maintain consistency in flavors while the product is in the tube. When brushing, the foaming action helps distribute the paste in the mouth and then helps to remove debris from the mouth for better rinsing.
D&C Yellow #10 and D&C Red #30
Synthetic dyes produced from petroleum or coal tar sources; these dyes are approved by the U.S. Food and Drug Administration (FDA) for use in pharmaceuticals and cosmetics.
FD&C Blue #1
Synthetic dye produced from petroleum; this dye is FDA-approved for use in food, pharmaceuticals and cosmetics.
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Glycerin is a compound which can be used to balance and maintain moisture levels. In toothpaste, it prevents the product from drying out and helps to preserve the product - it also contributes to a good mouth-feel and improves flavor. It may be of animal origin, and is thus listed in the PETA's Caring Consumer guide as a byproduct of soap manufacture which typically uses animal fat.
Hydrated silica is a derivative of silicon dioxide (found in nature as sand or quartz). It is a clear gel that acts as an abrasive in gel toothpastes. In opaque toothpaste, hydrated silica acts as a secondary abrasive.
Mica is from the phyllosilicate mineral family - powdered white mica is used in a number of cosmetics, including toothpaste, for its sparkle. It is also used as a mild abrasive to aid in polishing of the tooth surface.
PEG-8 and PEG-12
The term "PEG" (polyethylene glycol) is used for synthetic polymers of ethylene oxide - in toothpaste they are used as a humectants and solvents. Humectants prevent water loss and act as stabilizers. (According to Environmental Working Group or EWG, these polymers can be contaminated with potentially toxic manufacturing impurities such as 1,4-dioxane.)
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Derived from petroleum, poloxamer 335 and 407 belong in the surfactant category, which allows oil-based ingredients to be dissolved into a water-based solution.
Propylene glycol is a small organic alcohol commonly used as a skin conditioning agent and in toothpaste as a humectant. It has been associated with irritant and allergic contact dermatitis as well as contact urticaria (hives) in humans; these sensitization effects can be manifested at propylene glycol concentrations as low as 2 percent.
PVM/MA Copolymer is a copolymer of methyl vinyl ether and maleic anhydride and is used as a binder.
Sodium benzoate prevents the buildup of micro-organisms in the toothpaste, which is good because keeping toothpaste cold in the fridge might make brushing sensitive teeth rather uncomfortable.
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Fluoride is one of the more controversial ingredients in toothpaste. According to theADA, fluoride is the most important ingredient for healthy teeth: It strengthens enamel, prevents cavities and fights plaque. The debate surrounding the safety of fluoride stretches back to the 1950s when the move to add fluoride to drinking water began. Fluoride ingested in unsafe levels is toxic to humans, and the FDA mandates warning labels on all products containing the chemical that reads: "Keep out of reach of children aged 6 and under. If more than is used for normal brushing is swallowed, contact your physician or local poison control center."
Except in rare cases of allergic reaction resulting in continued vomiting and dehydration, the worst symptoms of fluoride poisoning in children are diarrhea and nausea, according to the New York Times. Of the 4,453 cases of unintended ''fluoride exposure'' reported to poison-control centers last year, 99 percent were minor and not one was life-threatening.
Otherwise known as lye or caustic soda. In toothpaste it works to neutralize the pH of other ingredients.
Sodium lauryl sulfate (SLS)
Before the 1940s, toothpaste contained soap. Now SLS is used as the detergent part of the toothpaste, which makes the toothpaste lather in your mouth. (It's commonly found in shampoos for the same purpose.) SLS has a reputation for being a skin irritant, and in a study located in the U.S. National Library of Medicine, it was found that a significantly higher frequency of aphthous ulcers (canker sores) was demonstrated when the patients brushed with an SLS-containing toothpaste.
SLS Bonus! The ingredient is also responsible for the unpleasant taste of orange juice after you brush your teeth. SLS desensitizes the taste buds that pick up sweetness, so your tongue is getting only the sour and bitter flavors.
Since toothpaste manufacturers aren't going to add sugar to mask the many bitter flavors listed here - they turn to artificial sweeteners, like saccharin.
Sorbitol is a sugar alcohol used in food products and is used in toothpaste for sweetening, but it is also used as a humectant and texturizing agent.
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Titanium dioxide is an inorganic compound used as a colorant in a range of body care products such as sunscreens and makeup. It gives non-gel toothpastes their bright whiteness.
Titanium dioxide has been described as a possible human carcinogen by the Canadian Center for Occupational Health and Safety.
Triclosan is an ingredient added to many consumer products as an antimicrobial ingredient, especially in antibacterial soaps and body washes - but also in cosmetics and some toothpastes, where it is used to fight gingivitis. The chemical is so prevalent that a survey by the Centers for Disease Control and Prevention found the chemical present in the urine of 75 percent of Americans over the age of 5. Scientists have also found that one-third of the bottlenose dolphins tested off South Carolina and almost one-quarter of those tested off Florida carried traces of triclosan, from wastewater, in their blood.
Triclosan is listed by the EPA as a pesticide.
According to the FDA: "Animal studies have shown that triclosan alters hormone regulation. However, data showing effects in animals don't always predict effects in humans. Other studies in bacteria have raised the possibility that triclosan contributes to making bacteria resistant to antibiotics. In light of these studies, FDA is engaged in an ongoing scientific and regulatory review of this ingredient. FDA does not have sufficient safety evidence to recommend changing consumer use of products that contain triclosan at this time."
Xanthan gum is a polysaccharide, a sugar-based polymer produced by bacteria; it is used as a viscosity agent in personal care products and foods.
So there you have it. Most of us are careful and don't gulp down massive amounts of toothpaste, but according to the U.S. National Library of Medicine, swallowing a large amount of regular toothpaste may cause stomach pain and possible intestinal blockage. As well as convulsions, diarrhea, difficulty breathing, drooling, heart attack, shock, tremors and vomiting. The moral of the story? Rinse and spit well.