Have you ever been to a gourmet food festival, only to find that your taste buds have gone numb and the flavors of the dishes just don’t seem as vibrant? Losing your sense of smell and taste are increasingly common problems that can make eating meals unenjoyable.
It is also a side effect of COVID-19, where people who have the virus often experience symptoms like a decrease in sensitivity to flavors or an inability to distinguish between different tastes and smells.
If it’s been a while since you could savor the aroma of freshly brewed coffee, or taste the sweetness of a ripe apple, don’t worry. In this article, we’ll explore various causes for loss of taste and smell, its diagnosis process, and treatments for it.
How Your Sense Of Taste Works: Overview
Before we discuss any diagnosis and treatments for loss of taste, it’s important to understand the science behind how your sense of taste works.
Our sensory systems let us distinguish between about 100,000 different flavors. Located on the tongue and in the mouth, our taste buds work to detect five basic tastes: sweet, sour, bitter, salty, and umami.
These sensations are then sent to our brains, where they’re interpreted as flavors. Sense of smell also plays a major role in how we experience flavor because it helps us distinguish between different smells that can influence the taste of something.
For example, when you eat or drink something without tasting any flavor, your brain is still registering the smell and giving you a sense of that flavor.
The Science
When you eat or drink something, molecules from the food or beverage enter your nose, where they are picked up by olfactory receptors that then send signals to the brain.
The signals travel through a portion of the brain called the olfactory bulb and then onto the gustatory cortex, which is responsible for processing tastes. The olfactory bulb and gustatory cortex both work together to create the flavor of food or drinks that we experience.
The combination of taste and smell help us determine whether something is sweet, salty, sour, bitter, or savory.
What Causes A Loss Of Taste?
A loss of taste can be the cause of anything that blocks or disrupts the nerves responsible for transporting signals from your tongue to the brain. It might manifest in a loss of smell but not taste, a sudden loss of taste, or something different altogether. Common causes include:
Illness Or Infection
A cold, flu, or sinus infection can cause a temporary disruption in taste and smell. These types of infections are usually accompanied by nasal congestion, which can make it difficult to distinguish the flavors of food.
For example, when you have a cold, the inflammation in your nasal passages can affect your ability to smell, and since taste is closely linked to smell, it can also impact your sense of taste. Infections in the mouth or throat can directly affect the taste buds themselves, causing a temporary loss of taste.
Obstructions
Obstructions in the mouth or nose can block the flow of air and affect your sense of taste. Common with colds and allergies, a stuffy nose can make it harder to smell and taste food properly.
If you have a blockage in your mouth, such as a swollen or infected gland, it can affect the function of your taste buds. Obstructions can also cause dry mouth, further impacting your sense of taste.
Blockages in the throat or esophagus, such as tumors or strictures, can affect the passage of food and liquids and affect your ability to taste. This is because the taste buds in the throat and esophagus play a role in detecting the flavor of food as it passes through.
Certain Medical Conditions
There are a number of medical conditions that can affect your sense of taste. For one, neurological disorders, such as Alzheimer's disease and Parkinson's disease, affect the nerves that transmit signals between your taste buds and your brain.
On the other hand, conditions that affect the hormonal balance in your body, such as hypothyroidism or diabetes, can also cause taste bud changes. Uncommonly known, hormones can play a role in regulating your sense of taste.
Cancer And Treatment
Cancer and its treatment, such as chemotherapy and radiation therapy, can affect the cells in your mouth and tongue, resulting in a temporary or even permanent loss of taste.
Chemotherapy drugs can also affect your sense of taste by damaging the cells that produce saliva. Meanwhile, radiation therapy can cause inflammation and irritation in your mouth and throat, which can also affect your sense of taste.
Cancer patients may experience a loss of appetite or nausea that heavily impacts their enjoyment of food.
Medication
Medications can cause a loss of taste as a side effect. Antibiotics and blood pressure medications, for instance, can affect the cells in your mouth and tongue.
Some medications can also interact with each other and cause a loss of taste as a result. As mentioned, certain chemotherapy drugs can affect the cells that produce saliva. But, when taken together with other medications that have similar effects, it can further impact your sense of taste.
Vitamin Deficiencies
Vitamin deficiencies can also be the culprit if you’re losing your taste. Here are a few examples:
- Zinc deficiency can impact the structure of your taste buds and ultimately lead to a loss of taste.
- A lack of vitamin B12 can affect the health of your nerves, which can also contribute to taste loss.
- Vitamin A deficiency can impair your ability to detect specific flavors.
Ensuring that you're meeting your daily nutrient requirements can help maintain your taste sensitivity and overall enjoyment of food.
Smoking, Drugs, And Chemicals
Smoking can affect your sense of taste because it can damage the cells in your mouth and tongue that are responsible for detecting flavors. After a while, smoking can dull your sense of taste and make it harder to detect different flavors in food.
Exposure to certain chemicals can also cause a loss of taste. For example, exposure to lead, mercury, and other heavy metals can affect the function of your taste buds. Similarly, exposure to pesticides and other chemicals can cause changes in your sense of taste.
Aging
As we get older, our sense of smell usually begins to decline and become less sensitive. This can happen because our taste buds, which are responsible for detecting different flavors in food, can become less effective over time. In addition, the number of taste buds we have can also decrease as we age.
Other factors that can impact our sense of taste as we age include medications, medical conditions, and changes in our diet.
Loss Of Taste Treatment
Addressing the underlying medical condition: If the loss of taste is caused by an underlying medical condition, such as a common oral infection or allergy, treating that condition may help restore your taste.
- Adjusting medications: If a medication is causing a loss of taste, your doctor may adjust the dosage or switch to a different medication.
- Good oral hygiene: Maintaining good oral health, such as brushing your teeth regularly and using mouthwash, can have taste-altering effects.
- Quitting smoking: If you are a smoker, quitting smoking can help improve your sense of taste. Within 48 hours of quitting, nerve endings grow and improve your sense of taste again.
- Diet changes: Certain foods may help improve your sense of taste. For instance, eating foods that are high in zinc, such as oysters and beef, can help improve your sense of taste. Eating sour or acidic foods may also help stimulate your taste buds.
- Referral to a specialist: For more complicated cases, your doctor may refer you to a medical specialist, like an ear, nose, and throat (ENT) doctor or a neurologist, to help diagnose and treat the underlying cause of your loss of taste.
How Long Does The Loss Of Taste Last?
The duration of the loss of taste and smell depends on its cause. In most cases, it will last a few days or weeks until the underlying condition has been treated.
However, some people may experience a more prolonged period of time with no sense of taste or smell. If this is the case, they should see their doctor for further evaluation and treatment.
How Common Is Losing Your Sense Of Taste?
Losing your sense of taste entirely, also known as ageusia, is not very common. According to the Cleveland Clinic, about one or two out of 1,000 people will develop a complete loss of taste. The majority of people have a partial loss of taste.
That being said, a partial loss of taste, also known as hypogeusia, is more common and can affect people of all ages. Certain groups of people may also be more at risk for a loss of taste, such as those who smoke, have poor oral hygiene, or have existing medical conditions, such as allergies, infections, or neurological disorders.
Temporary Or Permanent Loss Of Taste
Temporary loss of taste is a common condition resulting from a range of factors, including viral infections, allergies, and medications. Luckily, it usually resolves on its own once the underlying cause is addressed.
On the other hand, permanent loss of taste is a rare condition that can be caused by certain medical conditions, such as nerve damage, head injuries, or neurological disorders. Permanent loss of taste can also be caused by certain treatments, such as radiation therapy to the head and neck.
While the temporary loss of taste is often reversible, permanent loss of taste is usually irreversible. People with permanent loss of taste can still enjoy food by focusing on other sensory experiences, such as texture, temperature, and aroma.
It’s often recommended to work with a registered dietitian or a professional chef to help with permanent loss of taste, find new ways to enjoy food, and maintain a healthy diet.
What Are The Symptoms Of Smell And Taste Disorders?
Smell and taste disorders can lead to a range of symptoms that you might not have even thought about before. This might include the following:
- Reduced sense of smell (hyposmia): A diminished ability to detect or distinguish odors.
- Altered sense of smell (dysosmia): A distorted or abnormal sense of smell, which may cause things to smell differently than they should.
- Loss of taste (ageusia): The inability to detect or distinguish tastes.
- Reduced sense of taste (hypogeusia): A diminished ability to detect or distinguish tastes.
- Altered sense of taste (dysgeusia): A distorted or abnormal sense of taste, which may cause things to taste differently than they should.
- Difficulty enjoying food: A reduced pleasure or enjoyment from eating.
Want to learn more about the loss of taste and smell? We’ve answered some frequently asked questions down below.
Is loss Of Taste And Smell A Symptom Of Omicron?
The Omicron variant of COVID-19 has been reported to cause loss of taste, just like other variants of the virus. These are actually common symptoms of COVID-19, regardless of the variant, but not everyone who gets infected will experience them.
How Long Does Loss Of Taste Last With COVID?
The duration of loss of taste (and smell) caused by COVID-19 can vary widely among individuals. For some people, it may only last a few days or weeks, while other cases may persist for several months.
According to a systematic review, the average duration of loss of taste or smell among people with COVID-19 was 7 to 14 days. However, note that this may differ and that it may be one of the last symptoms to resolve.
When Does Loss Of Taste And Smell Occur With COVID?
Loss of taste and smell can occur at any time during a COVID-19 infection. Despite this, it’s more commonly reported in the early stages of the illness, typically within the first week after infection. In some cases, loss of taste and smell may be the only symptoms a person experiences, and it may occur before other symptoms develop.
Studies have shown that loss of taste and smell may be more common in people with mild or asymptomatic COVID-19 infections than in those with more severe illnesses.
Can You Have COVID Without Loss Of Taste And Smell?
It's 100% possible to have COVID-19 without experiencing loss of taste or smell. While the loss of taste and smell is a common symptom of COVID-19, not everyone who is infected with the virus will experience this symptom. In fact, many people with COVID-19 have no symptoms at all, while others may have a range of symptoms that can vary widely in severity.
Can A Stuffy Nose Cause Loss Of smell And Taste?
The congestion from a stuffy nose prevents air from reaching the olfactory receptors, which are responsible for detecting scents and flavors. If this happens, you can try to clear out your nasal passages by taking decongestants or using a saline spray.
Can A Sinus Infection Cause Loss Of Taste?
Sinus infections lead to mucus build-up and a blockage of nerve endings in the deep nasal cavity. As smell and taste rely on each other so heavily, people will likely experience a loss of taste during the course of the infection.
Be sure to seek medical advice if you think you might be suffering from a sinus infection, as it can lead to further complications if left untreated.
Can Flu Cause Loss Of Taste?
Yes, the flu can cause loss of taste and smell. Because it’s a viral infection that causes inflammation in the sinuses, it can block off the pathways for smell and taste signals from reaching their destination.
Can Congestion Cause Loss Of Taste?
Congestion can cause loss of taste and smell, much like the flu does. It restricts the pathways for smell and taste signals to go where they need, resulting in a decrease in sensitivity to flavors.
Can Loss Of Taste Be Permanent?
It depends on the cause. In most cases, loss of taste and smell is temporary and may resolve once the underlying condition has been treated. Unfortunately for others, it may be permanent. This often occurs when damage is done to the nerves responsible for taste and smell.
Can Loss Of Taste Be A Sign Of Pregnancy?
It’s well-known that hormonal changes during pregnancy can affect the senses. Ever heard of “pregnancy cravings”? It’s possible that these cravings are due to changes in the sense of taste or smell.
Some women may end up with a heightened sense of taste, while others may experience a loss of taste or changes in taste preferences. This can manifest in a strong aversion to certain foods or smells that they previously enjoyed or a craving for specific foods.
It's worth noting that loss of taste alone is not a definitive sign of pregnancy.
