Senses of taste and smell often diminish as we age

Dear Doctor:

I’ve been gradually losing my senses of taste and smell. As a foodie and accomplished cook, this is disheartening. I’m in great health, and I hope it’s not just “getting old.” I’m 82 and would like to have my taste buds back.

Dear Reader: It may not sound like good news, but you’re actually a few decades late in experiencing a diminishment in your senses of taste and smell. While these types of disorders can occur at any age, they are increasingly common as people reach their 50s and 60s -- and beyond.

Since our senses of taste and smell are closely intertwined, it’s helpful to know how they work in order to understand what may be causing them to decline. In fact, in many cases, a diminishment in the sense of taste actually arises from issues relating to the sense of smell.

Taste begins when a solid or liquid comes into contact with taste receptors. These tiny sensory organs are found in the taste buds on the surface of the tongue, and in smaller numbers along the soft palate, the upper portion of the esophagus and the inner linings of the cheeks. In a series of complex steps, chemical signals are produced and analyzed, and the information is delivered via nerve impulses to the brain. The information that comes from the mouth translates into the five basic tastes -- salty, sweet, sour, bitter and savory, which is often referred to as umami. Receptors in the mouth also provide information regarding temperature, spiciness, fattiness and texture.

The infinite nuances of taste, which we think of as flavor, come to us via the nose. This occurs when chewing and swallowing send molecules through a specialized channel that leads from the throat to the nose, and again to the brain. The resulting nerve signals let you know not only the difference between a bite of raw potato and an apple, but provide the gradations of taste and aroma that make a Macintosh apple different from a Golden Delicious.

Although taste buds and olfactory nerve cells regenerate, the rate at which this happens slows down as we get older. Research suggests that the various environmental assaults that can damage these cells -- such as smoke, pollution, illness and injury -- may have a cumulative effect. Certain medications -- including some common antibiotics, antihistamines, cholesterol and blood pressure drugs, antidepressants, heart meds and pain medications -- can adversely affect the sense of smell, and thus blunt the sense of taste. So can smoking, dry mouth, a sinus infection and certain neurological conditions, like Parkinson’s disease and Alzheimer’s disease.

To learn more about what is happening, consider a visit to an otolaryngologist, also known as an ear, nose and throat doctor. They can conduct taste and smell tests to help pinpoint the scope and severity of what you’re experiencing.

Eve Glazier, M.D., MBA, is an internist and associate professor of medicine at UCLA Health. Elizabeth Ko, M.D., is an internist and assistant professor of medicine at UCLA Health.