Ageusia

Ageusia is the inability to taste sweet, sour, bitter, or salty substance. This disorder is incredibly rare. In Ageusia, an individual cannot taste anything applied to his or her tongue. Ageusia is a problem for many sufferers because it interferes with the enjoyment of food. Someone with Ageusia may eat less than he or she should, potentially experiencing malnourishment. The sense of taste is also critically important in detecting signs that food has gone “off,” in combination with the sense of smell, which means that someone with Ageusia may eat something which makes him or her sick.