Ever taken a gulp of orange juice after brushing your teeth, only to practically spit it out without swallowing? Turns out, the ingredient sodium lauryl sulfate (SLS), a lathering agent in toothpaste, is responsible. SLS leaves your mouth feeling fresh but has a different reaction, too. Because it both numbs the sweet receptors in your tongue and simultaneously destroys bitter-tasting receptors, the taste of juice is seriously altered, creating that "yuck" reaction [source: O'Hare].
How long should you wait between eating and brushing?
So, you've just brushed your teeth. Your mouth feels refreshed and your breath smells minty -- and you're hungry. Should you wait to eat after you brush? Will food damage your teeth you've just brushed? The general consensus from dentists we surveyed is no, you don't have to wait -- but there are some exceptions. Dr. Jeremy Rosenberg, a dentist in Atlanta, Ga., said, "Technically, the average person doesn't have to wait to eat after brushing. For someone who is cavity-prone, however, the fluoride in the toothpaste does benefit the enamel of the teeth. Once you eat though, most of the fluoride will be washed away."
The cycle of eating and brushing can get tricky if you don't need to wait to eat after you brush, and then you brush after you eat -- over and over again during the day. If you eat sugary or acidic foods or drinks, the enamel on your teeth will be softened. Therefore, brushing right after you eat may not be wise. Dr. Rolfe explains that if you just had an acidic or sugary snack, you should gargle with a fluoride mouthwash and not brush your teeth. The damaging food or drink will soften the teeth surface, so if you brush right away, you will actually abrade a lot of tooth structure in the process. Dr. Rolfe recommends rinsing with water after eating, but wait for about 20 minutes before brushing.
Dr. Rosenberg explains that chewing sugarless gum always helps if you can't brush for a while because it stimulates saliva production, which helps to neutralize acids and fight bacteria in your mouth. Flossing or rinsing will also help dislodge any food particles that may become stuck between your teeth, and tongue scrapers are a good tool for removing bacteria that are stuck to the surface of your tongue. When you do brush your teeth, Dr. Rosenberg also suggests you gently clean the roof of your mouth and gums to remove extra bacteria.