What causes loss of taste when sick?

September 28, 2025 •

4 min read

According to the National Institute on Deafness and Other Communication Disorders, the perception of flavor is a complex process involving both taste and smell. This crucial relationship is why a key answer to the question, "What causes loss of taste when sick?" is often related to a blocked sense of smell, not your taste buds themselves.

Quick Summary

Illnesses often cause a loss of taste due to inflammation and congestion, which disrupt the connection between your senses of smell and taste. When your nasal passages are blocked, odors from food cannot reach the olfactory receptors, resulting in a significantly dulled perception of flavor. Your ability to taste will typically return as the congestion subsides.

Key Points

Smell, not taste, is the culprit: The majority of flavor perception is tied to your sense of smell, which gets blocked during illness, muting the flavors of food.
Congestion is the main cause: Illnesses like colds, flu, and sinus infections cause inflammation and mucus buildup in nasal passages, preventing aromas from reaching your olfactory receptors.
Recovery is usually temporary: For most viral infections, your sense of taste and smell will return to normal once the congestion clears and you recover.
Beyond infection: Other factors like medications, poor oral hygiene, and chronic conditions can also impact taste, so a persistent issue warrants a doctor's visit.
Managing symptoms: Focusing on strong, simple flavors and varied food textures can make meals more enjoyable even with a reduced sense of taste.

The Surprising Connection Between Taste and Smell

The perception of taste is a complex sensory experience, far beyond what our tongue's taste buds can detect on their own. While the tongue identifies basic tastes like sweet, salty, sour, bitter, and umami, the majority of the rich, nuanced flavors we enjoy actually come from our sense of smell. When you chew and swallow food, it releases aromatic compounds that travel up the back of your throat to the nasal cavity, where millions of olfactory (smell) sensory neurons are located. These neurons are responsible for sending signals to your brain that, combined with the signals from your taste buds, create the complete sensation of flavor.

When you get sick with a cold, the flu, or another viral infection, the inflammatory response in your body causes the tissues inside your nose to swell. This congestion and excess mucus can physically block the nasal passages, preventing food aromas from reaching the olfactory receptors. It's this interruption of communication between your nose and brain that causes food to taste bland or nonexistent, not a problem with your taste buds themselves.

Common Illnesses That Affect Taste

Several common illnesses are known to cause a temporary loss of taste. The most frequent culprits include:

The Common Cold: One of the most classic examples, where congestion is the main driver behind a muted sense of flavor.
Influenza (Flu): Similar to a cold, the flu's ability to inflame the respiratory tract leads to congestion and, subsequently, a loss of taste.
Sinus Infections (Sinusitis): Inflammation of the sinus cavities, whether viral or bacterial, can block nasal passages and impair both taste and smell.
COVID-19: As a widely reported symptom during the pandemic, COVID-19 can cause a complete or partial loss of taste (ageusia or hypogeusia), sometimes even without other respiratory symptoms. The mechanism is thought to involve damage to cells that support the olfactory sensory neurons.

Other Factors That Disrupt Your Sense of Taste

Beyond respiratory infections, other conditions and factors can cause a loss or alteration of taste. It is important to consider these, especially if the taste disturbance persists after your illness has resolved. These can include:

Medications: Some drugs, including certain antibiotics, antihistamines, and blood pressure medications, can alter taste as a side effect. This is sometimes described as a metallic or bitter taste, a condition known as dysgeusia.
Poor Oral Hygiene and Dental Problems: Infections in the mouth, gum disease, or even extensive plaque buildup can interfere with taste sensations.
Neurological Conditions: Diseases that affect the brain and nervous system, such as Alzheimer's and Parkinson's disease, can impair the processing of smell and taste signals.
Vitamin or Mineral Deficiencies: A lack of certain nutrients, particularly zinc, can impact taste function.
Aging: As we age, our senses of taste and smell can naturally decline.

The Difference Between True Taste Loss (Ageusia) and Smell-Related Loss

It's important to distinguish between a full loss of taste (ageusia) and the more common smell-related loss. Most people experiencing a dulled taste during a cold are actually suffering from hyposmia (partial loss of smell) or anosmia (complete loss of smell), which in turn, affects their ability to perceive flavor. True ageusia, where the tongue's ability to detect basic tastes is lost, is rare, though it can occur in cases of nerve damage or advanced illness.

How to Manage Loss of Taste While Sick

While time is often the best cure, there are ways to manage and enhance your eating experience when your taste is diminished:

Focus on Texture: Since your sense of touch in the mouth is unaffected, focus on foods with interesting textures. Incorporate crunchy, creamy, or chewy elements to make meals more satisfying.
Use Strong Flavors: Experiment with strong, simple flavors that don't rely heavily on aroma. Spices, hot sauces, or acidic components like lemon juice can sometimes break through the muted taste perception.
Enhance with Aromatics: Adding fresh, aromatic herbs like mint, basil, or cilantro to dishes can help stimulate what little sense of smell you have, offering a more complete flavor experience.
Try Different Temperatures: Some people find that chilled or frozen foods, like yogurt or smoothies, are more appealing than hot food when sick.

What to Do If Your Loss of Taste Persists

For most people, taste returns to normal once the illness passes. However, if your symptoms persist for more than a few weeks, it's a good idea to consult a healthcare provider. A prolonged loss of taste or smell can sometimes indicate a more serious underlying issue, such as a chronic sinus infection, nasal polyps, or a lasting effect from a viral infection. A doctor can help diagnose the root cause and recommend the appropriate treatment plan. For authoritative medical guidance, it's always best to consult a professional or check reputable health sources like the Cleveland Clinic website.


Cause Category	Effect on Taste	Typical Duration	Treatment Approach
Viral Infections (Cold/Flu/COVID-19)	Primarily a muted sense of flavor due to blocked smell	Temporary; usually resolves with recovery	Rest, hydration, decongestants to address congestion
Medications	Can cause altered or metallic taste (dysgeusia)	Varies; often resolves when medication is changed or stopped	Consult a doctor about medication alternatives
Chronic Conditions (e.g., Sinusitis, Allergies)	Can cause persistent or recurring taste loss	As long as the underlying condition is active	Manage the chronic condition with doctor guidance
Neurological Issues	Can cause complete loss of taste and altered perception	Potentially long-term or permanent	Addressing the underlying neurological disorder

Conclusion

The loss of taste experienced when sick is a common and temporary side effect of the congestion and inflammation associated with viral infections. While it can be frustrating, understanding that your sense of smell, not your taste buds, is the primary culprit can provide clarity. Most people will find their flavors return once they recover. If the issue lingers, however, it's always wise to seek medical advice to rule out other potential causes and ensure a full return to enjoying your favorite foods.

Frequently Asked Questions

No, common illnesses like a cold or flu do not typically damage your taste buds. The loss of taste is a result of nasal congestion and inflammation temporarily blocking your sense of smell, which is responsible for the majority of flavor perception.

The duration of taste loss varies depending on the illness. For most respiratory infections, your sense of taste will return gradually as your congestion clears, usually within a few days to a couple of weeks. However, more severe infections like COVID-19 can cause a longer-lasting effect for some.

Yes, some medications can have a side effect of altering or reducing your sense of taste. This can be more noticeable when you are sick. If you suspect your medication is the cause, it is important to speak with a healthcare provider.

A metallic taste, known as dysgeusia, can occur due to various reasons, including certain medications or underlying health conditions. Some viral infections or acid reflux, which can be exacerbated when sick, might also cause this altered taste sensation.

Ageusia is the complete loss of your sense of taste, while hypogeusia is a partial loss. The loss of taste experienced with a cold is often technically hypogeusia, or simply a diminished sense of flavor, because the tongue can still detect basic tastes.

Yes, allergies can cause inflammation and congestion similar to a viral infection, leading to a temporary loss or reduction of taste and smell. As with an illness, managing the underlying allergic reaction should help restore your senses.

If your loss of taste is prolonged, doesn't improve after your other illness symptoms resolve, or is accompanied by other concerning symptoms, you should consult a doctor. This is particularly important if the loss of taste or smell is sudden and severe.