by Joel Portnoy, M.D.
Our senses of taste and smell give us important information about our environment. Smell and taste problems can affect people's day-to-day life leading to substantial dissatisfaction and sometimes danger (ex. gases, fumes, etc.). Most our sense of taste comes from combining taste information (collected by the taste buds on the tongue) with smell information (collected by smell nerve fibers in the top of the nose). However, some taste sensation is supplied exclusively from the tongue, including sweet, salty, bitter, and sour substances.
Primary problems of taste, called dyspepsia, can be from local tissue inflammation of the tongue, gums or mouth, distorted by medications or from a more serious medical issue. Spicy foods result in local tissue inflammation of the mouth and throat, rather than a true “taste.” Problems with the sense of smell can arise from changes affecting the nose, the nerve fibers bringing the signal from the nose to the brain, or the brain itself. Our sense of smell relies on proper airflow through the nose to reach the nerve fibers that project from the brain into the nasal cavity. If nasal airflow is blocked (nasal congestion [link to nasal congestion], polyps, a growth, etc.), the signal may not get through. Because taste is so closely linked to smell, this may alter the way that food usually tastes. This effect can last for weeks following resolution of an illness.
Other reasons such as chronic nasal swelling [link to nasal congestion], allergies [link to allergies], normal aging, growths along the smelling nerves and conditions affecting can lead to reduced or changed smell. If you are having persistent changes in your sense of taste and/or smell, see an ear, nose and throat doctor promptly.