Loss of smell and taste in common cold

close

01/6An impaired sense of smell is a common symptom of COVID-19

The novel coronavirus brought along several symptoms ranging from a mild fever, persistent cough, fatigue to a more mysterious ailment i.e. the loss of sense of smell and taste, also known as anosmia. While it causes no severe complications in the body, the condition itself can be quite distressing and life-altering, affecting the quality of life in several ways.

Experts have also claimed that an impaired sense of smell can linger on days after a COVID-19 infection, which is why it is also a sign of long COVID. However, the olfactory system can be affected by many other reasons. Other than the SARs-COV-2 virus, loss of sense of smell can be triggered by other factors. Find out what they are.

Also read: Explained: How coronavirus blocks your smell

02/6Nasal polyps

Nasal polyps are noncancerous growths in nasal passages that are painless, but discomforting. These can hang down to the opening of the nostrils or extend down to the throat region, causing blockage to the nasal passage, leading to congestion, breathing problems, headache, and loss of smell. Nasal polyps are a result of chronic inflammation, allergies, or certain immune disorders.

Also read: Skipping breakfast increases dementia risk by four times: Study

03/6Allergies, sinusitis, flu, common cold

Just like COVID-19, various other respiratory viruses can lead to smell loss. Infections such as a regular common cold or a flu infection can cause anosmia, which can linger on for some time. Severe allergies and chronic sinus problems are some of the common causes of smell loss. Loss of smell and taste with allergies is caused by nasal congestion. Given that your nasal passage is blocked for whatever reason, it becomes difficult for the particles to reach the nerves in your nose responsible for smell functions.

04/6Aging

The nasal cavity has olfactory receptors that send information through nerves to the brain, facilitating functions like smell. That said, conditions like anosmia can occur if the nerves suffer from any damage. That said, losing one's sense of smell and taste can be a possible outcome of aging as the nerves and the receptors weaken over time, as people get older. The condition is also known as presbyosmia, which refers to the gradual degeneration of sense of smell due to ageing process, prevalent in those aged 70 and above.

05/6Head injury

One can lose their sense of smell post a traumatic head/brain injury. This is because some parts of the brain are linked to the olfactory system. The orbitofrontal cortex, located above and behind the eyes, the insula, which lies beneath the ears, the piriform cortex, which is situated between the other two parts are associated with the smell functions. A head injury can lead to damage to any or all of these areas, causing anosmia.

06/6Medications can also affect the sense of smell

Certain medications and toxic chemicals can also impair people's sense of smell. Antibiotics such as ampicillin and tetracycline, decongestant nose sprays, some antidepressants and antihistamines can lead to anosmia.

Several viruses and health conditions, including COVID-19, could be the reason for your 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.

Here Kevin Hur, MD, a rhinology specialist at Keck Medicine of USC, outlines 4 common reasons that may cause you to lose your sense of taste or smell.

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, or a complete inability to detect odors. Scientists have also identified a loss of taste and smell among the symptoms associated with COVID-19.

“Viruses can damage the cells that detect odors and cause swelling in your nose, which limits airflow to smell receptors, says Dr. Hur, an assistant professor of clinical otolaryngology – head and neck surgery at Keck School of Medicine of USC.

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. Neurological conditions

”Some neurodegenerative conditions that affect the nervous system, such as Alzheimer’s disease, Parkinson’s disease and multiple sclerosis (MS), may affect areas of the brain responsible for processing odors that affect a patient’s smell and taste,” says Dr Hur.

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.

“Nasal polyps eventually can grow to a size that prevents airflow to the cells that detect odors,” Dr. Hur says.

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 in 4 Americans over the age of 40 may experience changes in their sense of smell; that number increases to nearly 1 in 3 for people over the age of 80. When it comes to taste, 1 in 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 is a freelance writer covering health, culture, travel and parenting.