Doty feels taste recognition is more complex. “A given taste bud can have any combination of receptors found on the papillae, those little bumps on your tongue. One particular bud may have a receptor to only recognize a salty flavor, another bud may have a sweet, sour, and salty detector. It varies among individuals,” he says.
Using mice, scientists have demonstrated a crucial link between detecting chemicals via the taste buds and your brain being able to recognize them. Micewithout two key receptors that bind to a chemical that helps transmit tastes to the brain no longer responded to taste stimulation.
Determining more about the sense of taste could have interesting benefits. “Bitter foods were generally a warning of danger, so we didn’t eat them,” says Doty. But that means we tend to reject anything bitter, even products that might be good for us, like medications.
“If we can block your recognition of bitterness, we may be able to encourage you to eat foods that are good for you, but whose taste you don’t like. Companies are working on using alterations to make bitter medicines taste better.
The key is making such blockers short-acting, so they don’t permanently alter our bitterness alert protective mechanism,” says Battey.
What affects your flavor recognition skills?
A few medications can have a taste-corrupting effect. “Lamisil, a medicine for fighting toenail fungus, can knock out the taste function. Some medications related to heart problems, like ACE inhibitors and statin drugs, seem to distort taste,” says Doty.
Otherwise, it seems to be smell disruptors that are actually affecting your sense of taste. Among these factors:
• Dying smell-sensing cells are no longer replaced by new ones
• Whiplash, or otherwise falling and hitting the back of your head, affects sensory fibers
• Damage to nasal membranes from chronic colds and sinus infections “A decreased sense of smell can be an early warning of the onset of Alzheimer’s or Parkinson’s disease,” says Doty, though he emphasizes such a loss doesn’t automatically signal these conditions.
Dangers of taste/smell malfunctions
Taste and smell are classified as “chemosensory disorders” by the government. So important are these disorders to older people that the government has added information on them to its NIH website (http://nihseniorhealth. gov).
“A big issue with older people is eating enough and eating the right things. Since sense of taste is one of the things that drives desire to eat, affecting it can cause weight loss,” says
What can you do?
Find an allergist or neurologist who is using a technique Doty developed about 20 years ago. It features a scratch and sniff booklet containing 40 different odors the patient needs to identify.
A more comprehensive evaluation can be done at a few key taste/smell centers like Doty’s. The test takes five hours, but people find it worthwhile for many reasons. “Sometimes we can reassure someone that their problem is treatable. Otherwise we offer other advice,” he says.
“For example, practice smelling a series of odors before bed and that can bring back more function.You can use mouthwashes and certain antioxidant agents to minimize bad tastes. Sometimes there are ways to help you bring back at least partial sensitivity. The sooner you recognize your problem the more likely that will be,” says Doty.
“Most people take their senses of taste/smell for granted until they start to lose them. When their food starts tasting like cardboard, or they experience distorted tastes, then people seek help,” says Doty. Unfortunately, he adds, “Once your sense of smell has truly been damaged it is often permanent, affecting your sense of taste.
“If all else fails, experts can counsel you on how to cope with your loss, and put you in touch with support groups to help you,” says Doty.