Dulled sense of taste can have many causes
Q: Over the past year or so I've noticed that my sense of taste isn't as sharp as it used to be. What could be happening?
A: Taste buds line your tongue, throat and the back of the roof of your mouth. When food or drink stimulates them, they send a message to your brain allowing you to identify the taste as sweet, sour, bitter, salty or savory.
In addition, thousands of nerve endings on the moist surfaces of the eyes, nose, mouth and throat help you experience the food you're eating. They convey sensations such as heat, cold and texture.
The aroma of food is also an important element of taste. A food's aroma travels from the mouth to the nose via a channel at the top of the throat. That's why it's difficult to taste anything when your nose is stuffed up.
Since the mechanisms of taste are complicated, it makes sense that there are many ways for them to go wrong. Here are a few of the more common problems:
• Since smell and taste are so intricately linked, a problem with smell can make foods lose taste. Your sense of smell can be impaired by a blocked-up nose. Common conditions that cause nasal stuffiness may impair taste, including allergies, secondhand smoke, a sinus infection, or infection or small growths in the nose.
• Many medicines, including some antibiotics and antihistamines, can alter your sense of taste. Tell your doctor if you recently started taking a new medication and are experiencing a change in your sense of taste.
• Dry mouth causes your mouth and throat to feel severely parched. It also affects your ability to taste because saliva has a complex impact on taste. Many commonly used medicines (such as antihistamines) can cause dry mouth.
• After age 50, the number of taste buds starts to decrease. As a result, your sense of taste may decline with age.
• Cigarettes damage taste buds, dulling the sense of taste. The good news: If you quit, your sense of taste returns.
• More serious problems, such as diabetes, liver disease, kidney disease, Alzheimer's disease and Parkinson's disease, can diminish the senses of taste and smell.
I have a theory (unproven) that some viral infections can affect the nerves that send smell and taste signals from the mouth and throat to the brain. I had a bad viral infection when I was a preteen, and since then my sense of smell has not been as good.
If you've noticed a change or a problem with taste that lasts for more than a week or two, it's worth talking to your doctor
• Dr. Anthony Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK.com, or write: Ask Doctor K, 10 Shattuck St., Second Floor, Boston, MA 02115.