My wife says she has a sweet tooth. But doesn’t everyone? It’s universal to the human condition (as well as the human palate) to like something sweet.
It may even be an evolutionary advantage to seek out an energy source in the form of carbohydrates. Sweet meant ripe, and ripe meant more energy and a better safety profile. In fact, sweet preference is associated with fruit consumption. So next time your kids ask you for sweets, just think how well adapted they are.
Of course, it’s nothing to do with your teeth. “Sweet tooth” is just an expression, used in the same way as “a head for heights”, “an ear for music”, “a nose for trouble” or “an eye for a bargain” to denote a particular talent, as well as a proclivity towards it. In more recent times, this latter meaning has dominated and the sweet tooth has largely become a depiction of gluttony. But is there also a skill to it?
Taste perception begins on the tongue and soft palate, where receptors on the cluster of cells that make up the taste bud interact with food or beverages and the saliva in which they’re dissolved. These can respond not only to simple sugars but also other chemicals. This is how sugar substitutes (like saccharin, acesulfame K and aspartame) are able to taste as sweet as table sugar. But much less is needed to elicit the same sweet taste, and this means fewer calories.