Sugar-free gum helps clean teeth by stimulating the production of saliva. Saliva is nature’s way of washing away acids produced by the bacteria in your mouth, and it also bathes the teeth in bone-strengthening calcium and phosphate. In addition, many varieties of sugarless gum are sweetened with xylitol, an alcohol that reduces bacteria.
You might want to stick with mint flavors, however. One 2011 study suggests that the acid used to create certain fruit flavors could damage teeth, though only slightly. “Anything we taste as sour is more acidic, but we’re getting so much good out of the saliva flow, I could live with that,” Messina says.
Water, like saliva, helps wash sugars and acid off teeth. It also contains fluoride, a mineral that protects against tooth erosion and is found in toothpaste and some mouthwashes.
Fluoride occurs naturally in water (including some bottled spring water), and most tap water in the United States is also fortified with it.
Milk and other dairy products are the primary dietary source of calcium, which is essential for healthy teeth. Calcium is the key ingredient in a mineral, known as hydroxyapatite, that strengthens tooth enamel as well as bones. (Teeth aren’t bones, technically, but they share some of the same properties.)
Dairy products—especially cheese—also contain casein, a type of protein. Research suggests that caseins, along with calcium, play an important role in stabilizing and repairing tooth enamel
Leafy vegetables and other high-fiber foods promote good digestion and healthy cholesterol levels, and they also do wonders for your teeth—mostly because they require a lot of chewing.
Eating a bowl of spinach or beans is a bit like running your teeth through a car wash: All that chewing generates saliva, and the food itself physically scrubs your teeth as it’s mashed up into little pieces. “It’s the Milk-Bone dog biscuit benefit,” Messina says.
These summer berries contain malic acid, a natural enamel whitener. Here’s how to make your own at-home whitening treatment: Crush a strawberry to a pulp, mix it with baking soda, and spread it on your teeth using a soft toothbrush. Five minutes later, brush it off, rinse and voila: a whiter smile. (Be sure to floss, though, as tiny strawberry seeds can easily get trapped between your teeth.) – Health
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