Ear, Nose and Throat

What Can Cause a Loss of Taste and Smell?

Originally published June 12, 2020

Last reviewed June 17, 2022

Reading Time: 3 minutes

Do you like to take time to smell the roses, but lately, they don’t smell as sweet? Several viruses and conditions, including COVID-19, could be the culprits behind a loss of taste and smell.

A bouquet of flowers. A home-cooked meal. Milk that’s past its best-by date. Our senses of taste and smell help us to detect and catalog a wide spectrum of flavors and scents. Both can also serve to tell us when something’s not safe to eat. And, interestingly, what we perceive as a disruption in our ability to taste may often be rooted in issues related to our sense of smell.

Smell disorders can present different symptoms, including:

  • Hyposmia — a lessened ability to detect odors
  • Anosmia — a complete inability to detect odors
  • Parosmia — a change in the normal perception of scents (e.g., what used to smell pleasant is now foul)
  • Phantosmia — the perception of an odor that is not present

If you’re experiencing issues with your ability to taste and smell, here are some of the conditions that may be at the root of these changes.

1. Viral infections, like the flu, colds and COVID-19

If you’ve had a cold, you may be all too familiar with a stuffy nose that makes it hard to smell. In fact, both the common cold and influenza can cause temporary anosmia. Scientists have also identified a loss of taste and smell among the symptoms associated with COVID-19.

When smell is lost, often taste is, too. When you chew food, the released aromas reach your nose and activate your sense of smell. If your nose is stuffed or blocked by a cold or the flu, the odors can’t reach the sensory cells in your nose, and you lose much of the enjoyment of flavor. Foods taste bland and lose nuance.

2. An early sign of neurological conditions

Smell and taste are processed through the brain, so it might not be surprising that conditions affecting the brain, like Parkinson’s disease or Alzheimer’s disease, are linked to disruptions or a loss of these senses, especially smell.

It’s important to note that just because you’re experiencing a loss of smell it doesn’t mean you will develop Parkinson’s. But reduced sense of smell, or hyposmia, is often an early sign of the disease.

3. Nasal polyps

If you’re prone to frequent sinus infections, you may develop nasal polyps, or benign growths in the nose that may affect smell, due to inflammation of the lining of the nose that can prevent odors from reaching smell nerves.

Treatment may include topical medications, such as steroid sprays and nasal saline rinses, that shrink the polyps. In some cases, surgery also may be performed.

Once inflammation is under control, a full sense of smell may return.

4. Age

According to the National Institutes of Health, up to 1-4 Americans over the age of 40 may experience changes in their sense of smell; that number increases to nearly 1-3 for people over the age of 80. When it comes to taste, 1-5 Americans may experience changes after they turn 40.

As we age, several factors can contribute to a loss of taste and smell, including dental issues, dry mouth, certain medications, alcohol consumption and smoking. In addition, less mucus production in the nose, a loss of nerve endings and changes in the taste buds can occur as we age, affecting smell and taste.

If you’re experiencing a loss of taste and smell, talking to your primary care physician or visiting an otolaryngologist, a doctor who specializes in the conditions of the ear, nose and throat, may help you pinpoint what’s causing these changes in your senses.

Topics

age-related conditions
COVID-19
loss of taste and smell
nasal polyps
neurological conditions
Tina Donvito
Tina Donvito is a freelance writer covering health, culture, travel and parenting.