The loss of smell, known as anosmia, or a reduced sense of smell, called hyposmia, impacts millions of individuals, affecting daily activities from enjoying food to detecting hazards. Understanding its causes and available recovery strategies offers hope for regaining this important sense. Recovery is often possible, depending on the underlying reason for the smell loss.
Understanding Why Smell is Lost
Many factors can lead to a diminished sense of smell. Viral infections, such as the common cold, influenza, and COVID-19, are frequent culprits, causing inflammation and swelling within the nasal passages that block odor molecules from reaching the olfactory nerve. Viruses can also directly damage the olfactory sensory neurons, which are responsible for detecting and transmitting odor information to the brain. This damage can result in a sudden, complete loss of smell that may persist for months or even years.
Nasal polyps, which are benign growths in the nose or sinuses, also commonly impair smell by physically obstructing the airflow to the olfactory receptors. These polyps develop due to chronic inflammation of the nasal lining, preventing odor molecules from reaching the sensory cells. Allergies and chronic sinusitis similarly cause inflammation and congestion, leading to a blocked nasal cavity and reduced or absent smell. Head injuries can damage the olfactory nerve or related brain pathways, resulting in smell loss. Normal aging, particularly after age 65, also contributes to a gradual decrease in the sense of smell as nasal membranes thin and nerve function declines.
Strategies to Regain Your Sense of Smell
Olfactory training, also known as smell training, involves repeatedly exposing individuals to various scents to encourage smell recovery. This technique involves sniffing a set of four distinct odors, such as rose, eucalyptus, lemon, and clove, twice daily for at least 20-30 seconds each, over an extended period. This practice aims to stimulate and potentially regenerate the olfactory nerves, strengthening neural connections between the nose and the brain. Consistent training over several months, potentially up to a year, may lead to significant improvement in smell function, particularly for post-infectious smell loss.
Addressing underlying medical conditions is another direct path to restoring smell. If nasal polyps are the cause, treatment often involves intranasal corticosteroids to reduce inflammation and shrink them. Oral corticosteroids may be prescribed for more severe cases. When polyps are large or medical treatments are insufficient, functional endoscopic sinus surgery (FESS) can remove the growths and open the nasal passages, improving airflow and potentially restoring smell perception.
When to Consult a Doctor
It is advisable to consult a healthcare provider if smell loss persists beyond a few weeks, especially after a cold, allergy, or sinus infection has cleared. While many cases of smell loss from common infections resolve spontaneously, prolonged anosmia or hyposmia warrants medical attention to identify the underlying cause and rule out more serious conditions.
Seeking professional medical advice is also important if the loss of smell occurs suddenly, or if it is accompanied by other symptoms like headaches, vision changes, memory problems, or difficulty walking. A medical evaluation can help determine if the smell loss is due to an infection requiring antibiotics, a physical obstruction like a nasal polyp that might need removal, or a less common neurological condition. Early diagnosis allows for timely and appropriate treatment, which can improve the chances of smell recovery.
Living with Altered Smell While Recovering
Experiencing altered smell, such as parosmia (distorted smells) or phantosmia (smelling things that aren’t there), can be challenging during recovery. To enhance food enjoyment, individuals can focus on the texture, temperature, and visual appeal of meals, as these sensory inputs remain intact. Eating simpler, more bland foods or consuming them at cooler temperatures can help reduce the intensity of unpleasant distorted smells.
Safety measures become particularly important when smell is impaired. Regularly checking smoke detectors, ensuring gas appliances are turned off, and carefully verifying food expiration dates are necessary precautions. Labeling stored food with preparation dates can also help prevent consuming spoiled items. Connecting with support groups or online communities can provide emotional validation and practical tips from others navigating similar experiences, reducing feelings of isolation.