All food is made of chemicals—even food that grows on trees or in the ground. (Bananas, eggs and blueberries still have component parts like glucose, aspartic acid, butraldehyde and phenylalanine.) Some of these chemicals nourish us; others are connected to taste or color. And like any chemicals, the chemicals in food interact in sometimes curious ways.
Take, for instance, the disgusting taste that comes from putting pretty much any food stuff in your mouth after you've just brushed your teeth. What's going on there?
In the video above, the American Chemical Society explains that one toothpaste chemical in particular—sodium lauryl sulfate—seems to alter your mouth's ability to detect tastes. What we call "taste" is, actually, chemicals in food binding to specialized receptors on your tongue—your taste buds. Sodium lauryl sulfate, ACS explains, blocks the receptors that sense “sweet” and ramps up the ones for “bitter.” With your sense of sweet temporarily cooked, it's no wonder everything suddenly tastes a litte weird.