Sweet is one of the five basic tastes and is almost universally regarded as a pleasurable experience. Foods rich in simple carbohydrates such as sugar are those most commonly associated with sweetness, although there are other natural and artificial compounds that are much sweeter, some of which have been used as sugar substitutes for those with a sweet tooth. Other compounds may alter perception of sweetness itself.
The chemosensory basis for detecting sweetness, which varies among both individuals and species, has only been teased apart in recent years. The current theoretical model is the multipoint attachment theory, which involves multiple binding sites between sweetness receptor and the sweet substance itself.