They may not be as serious as cancer or heart disease, but problems
with smell and taste can make life miserable. Just ask the more
than 250,000 Americans who visit their physician every year because
of a "chemosensory" disorder.
"People with a smell or taste disorder really have a lower quality
of life," says Dr. Gary Beauchamp, director of the Monell Chemical
Senses Center in Philadelphia, funded by the National Institute
on Deafness and Other Communication Disorders. "They can't fully
enjoy the simple aspects of normal life, like eating and drinking,
and this can be a real challenge for them. For some of these people,
enjoying food and beverages may be one of the few pleasures they
have in life."
Who are these people? Adults over the age of 60 are the ones most
likely to have a problem with smell and taste, with loss of smell
occurring more frequently than loss of taste. Nearly one-third
of all Americans between the ages of 70 and 80 have a problem with
smell and about two out of three people over the age of 80 do.
It is normal for smell and taste to gradually decline in older
people. Taste disorders occur more frequently among older adults
who are taking several medications, while colds and upper respiratory
infections are the most common cause of smell disorders, followed
by medications and head injuries.
Even though chemosensory loss is common among seniors, the causes
are still not well understood. To help seniors learn more about
smell and taste problems, NIDCD has added these two topics to NIHSeniorHealth.gov,
a web site with formats and topics tailored to the needs of older
people, co-sponsored by the National Institute on Aging and the
National Library of Medicine.
Because the two senses are closely related, many people confuse
smell and taste disorders. A problem with taste may actually be
a problem with smell in disguise. (Most of us know what it's like
to lose the ability to taste food when our noses are stopped up
by a cold.)
Taste occurs because taste buds on our tongue, mouth and throat
have special cells that can identify five different sensations:
sweet, sour, bitter, salty and umami (savory). At birth we have
about 10,000 taste buds, but by age 50 that number may begin to
decrease, which may explain why some older people like saltier
and spicier foods. People with taste disorders often use flavor
enhancers to make their meals more palatable.
Smell and taste disorders
may not seem serious, but the loss of one or both could put an
older person in a potentially hazardous situation. According to
Beauchamp, smell lets us know when something in our environment
is wrong such as spoiled food or noxious fumes from a gas leak.
Taste also protects us by helping us select foods that are healthy
and good for us over those that might be bad. (Some plants that
are toxic may have a bitter taste, for example). "The ability to
identify food is especially important for people with food allergies," he
"And," he adds, "for some older people, especially the very old,
a smell or taste problem can be devastating. They no longer want
to eat or drink or maintain a nutritious diet and they can easily
slip into depression."
Researchers at Monell and other NIDCD-supported institutions are
looking at ways to restore smell and taste in people who've lost
"We're trying to understand at the molecular level why aging takes
its toll on smell and taste, and specifically why certain medications
exacerbate the problem. This work may eventually lead to new treatments
for individuals with chemosensory disorders," says Dr. James Battey,
In the meantime, it's important for older people to remember that
most cases of smell and taste loss are treatable, and some even
resolve spontaneously. Consulting a family physician can help older
adults identify the cause of the problem. A correct diagnosis is
important and provides a much-needed reassurance that the smell
or taste problem is not imaginary, adds Beauchamp.
"Some people find support groups helpful. Others prefer to use
online bulletin boards to share their experiences and come up with
various solutions. Regardless of the outcome, older people need
to remember that they are not alone. There are thousands of people
who are in the same situation," he says.
For more information on smell and taste disorders in older people,
For general information on smell and taste, see http://www.nidcd.nih.gov/health/smelltaste/index.asp.