The combination of toothpaste and orange juice has always been deemed a bad choice, but until now, no one really knew why.
Anyone who's ever brushed their teeth and then drank orange juice can attest to the bad taste it produces. But until now, no one was quite sure why this happened.
The American Chemical Society has explained why brushing your teeth and subsequently drinking orange juice is a bad combination, and it all has to do with our mouths.
Human mouths have around 10,000 taste buds with up to 100 individual taste receptor cells.
They're able to detect five different types of tastes: sweet, salty, bitter, sour and umami.
One of the primary ingredients in the detergent used in toothpaste is sodium lauryl sulfate, or SLS. It's what makes toothpaste get foamy while brushing.
SLS is also known to affect the mouth's ability to taste, specifically messing with the tongue's sweetness receptors.
SLS also destroys certain compounds found in the mouth, known as phospholipids.
These compounds usually inhibit the taste of bitter things, so they come off less strong, but when weakened by SLS, our mouths are more receptive to tastes we may not like.
Without the inhibitors in action, the bitterness is able to easily reach our receptors, causing the unpleasant flavor.
