The experience of an unusual or altered taste sensation following infection with SARS-CoV-2, the virus that causes COVID-19, is a widely documented phenomenon. This sensory disruption became a distinctive and early indicator of the infection for many people worldwide. Unlike a simple cold or flu, the way COVID-19 impacts taste and smell is often sudden, profound, and occurs without the typical nasal congestion. This loss of chemical senses is a direct consequence of the virus interfering with the body’s mechanisms for detecting odors and flavors.
Defining the Altered Sensations
The term “weird taste” encompasses several distinct medical conditions describing how the chemical senses are affected by the virus. Complete loss of taste is medically termed ageusia, which leaves an individual only able to perceive basic taste qualities like sweet, sour, salty, and bitter. More common is dysgeusia, a distortion of taste causing foods to register as unpleasant, metallic, rancid, or chemically altered when eaten. These taste issues are linked to problems with smell, as most flavor perception comes from the nose. A complete loss of smell is anosmia, but a particularly troubling symptom is parosmia, a distortion where familiar odors become foul, unpleasant, or unrecognizable.
How COVID-19 Affects Taste and Smell Pathways
The SARS-CoV-2 virus does not appear to directly attack the olfactory sensory neurons, the nerve cells responsible for detecting odor molecules. Instead, research indicates the virus primarily targets the sustentacular cells within the olfactory epithelium, the tissue lining the upper nasal cavity. These supporting cells express the ACE2 receptor protein that the virus uses as its entry point into human cells. By infecting and damaging these supporting cells, which provide metabolic and structural support, the virus indirectly disrupts the function of nearby olfactory sensory neurons, causing them to cease functioning correctly. This damage effectively cuts off the neural signaling pathway that communicates odor information to the brain, resulting in a sudden loss of smell perception. Because flavor perception is an integrated experience between the tongue and the nose, this olfactory disruption is the primary reason many people report an alteration of their sense of taste.
Timeline for Recovery
The loss of smell and taste is a temporary condition for most individuals, with the majority experiencing a relatively quick recovery. Studies show that the sense of smell begins to resolve within a few weeks, with the median recovery time reported to be about 11.5 days post-onset. Approximately 88% of patients report a return of their senses within two months following the initial infection.
However, a notable subset experiences persistent symptoms, often grouped under the umbrella of Long COVID. For these individuals, recovery can be a very slow process, sometimes taking six months or longer. Long-term studies have shown that approximately 88% of people who lost their senses fully regained them within two years, but some qualitative symptoms like parosmia or dysgeusia can be late-onset or remain for many months. Data also suggests that female patients and those who experienced a more severe initial loss of function may experience a slower rate of recovery.
Strategies for Restoring Taste
For those dealing with prolonged sensory issues, the most widely recommended strategy is olfactory training, often called “smell training.” This technique works by repeatedly exposing the olfactory system to distinct, strong scents, aiming to stimulate the nerves and encourage the regeneration of the olfactory pathway. The training typically involves using four distinct scent categories: floral, fruity, resinous, and spicy. Common scents used are essential oils of rose, lemon, clove, and cinnamon. Individuals are instructed to gently sniff each of the four scents for about 20 seconds, twice daily, for several months. Consistent, long-term practice is key to this neuroplastic process. Other supportive measures include maintaining good nasal hygiene and focusing on the texture and temperature of food to maximize the remaining sensory experience.