Most people who lose their sense of taste during COVID-19 recover it within one to three weeks, but for some, the problem lingers for months. The virus doesn’t directly damage your taste or smell neurons. Instead, it infects the support cells surrounding those neurons, triggering inflammation that disrupts how sensory signals reach your brain. Understanding that process explains why recovery is possible and what you can do to speed it along.
Why COVID Disrupts Taste and Smell
The virus targets support cells in the tissue lining your nasal cavity. These cells don’t detect odors themselves, but they do everything the sensory neurons need to function: regulating the chemical environment around the neurons, clearing old odor molecules so you can keep detecting new ones, and producing molecules that keep nerve cells healthy. When the virus infects these support cells, immune cells flood the area and release inflammatory signals that interfere with normal nerve function.
Because the neurons themselves are largely spared, recovery is a matter of the surrounding tissue healing and inflammation subsiding rather than regrowing nerve cells from scratch. This is good news. It means the wiring is intact, even if the signal is temporarily scrambled. Taste and smell are closely linked, so when your sense of smell is impaired, food often seems flavorless even though your tongue can still detect basic sensations like salty, sweet, and sour.
Smell Training: The Best-Supported Recovery Method
The World Health Organization’s 2025 clinical guidelines recommend olfactory training as the primary rehabilitation approach for persistent smell and taste problems after COVID. The technique is simple: you deliberately sniff a set of four strong, distinct scents twice a day for at least 12 weeks. The standard set, sometimes called the “Hummel four,” includes rose, clove, eucalyptus, and lemon.
Each session takes about 15 minutes. You hold each scent close to your nose and inhale gently for 15 to 20 seconds, actively trying to recall what it should smell like. Then rest briefly before moving to the next scent. This isn’t passive sniffing. The mental effort of connecting the stimulus to a memory appears to help retrain the pathway between your nose and brain.
You can buy commercial smell training kits, or make your own using essential oils on cotton pads stored in small jars. The specific scents matter less than consistency: pick four distinct categories (floral, spicy, herbal, citrus) and stick with them daily. The WHO notes that overall olfactory function improves in most cases, though the degree varies from person to person. Some people notice changes within a few weeks, while others need the full three months before things shift.
Dietary Strategies While You Recover
When food tastes like cardboard or worse, eating becomes a chore. A few adjustments to how you prepare and eat food can make meals more tolerable and even help stimulate whatever taste perception remains.
Tart and acidic flavors can be surprisingly helpful. Lemon juice, vinegar, and citrus fruits stimulate saliva production, and a dry mouth is one of the biggest enemies of flavor perception. Starting a meal with something tart, like lemon sorbet or a squeeze of fresh lemon over your food, can wake up your palate. If foods taste excessively sweet (a common distortion), adding something sour or slightly bitter helps balance it out.
Texture becomes much more important when taste is limited. Pairing crunchy foods like apple slices, celery, or crackers with something creamy or sticky like peanut butter creates variety that your mouth can still appreciate. Different tactile sensations can promote your appetite even when flavor is muted.
Temperature also matters. Many people find chilled or room-temperature foods more palatable than hot ones. Warm food releases more aromatic compounds, which can trigger unpleasant distortions if your smell is recovering unevenly. Yogurt, smoothies, chilled salads, and frozen fruit are worth trying. If you’re reheating leftovers, bringing them only to room temperature rather than piping hot can reduce off-putting smells.
Dealing With Distorted Taste
Some people don’t just lose taste. They develop parosmia, where familiar foods smell or taste rotten, metallic, or chemically wrong. Coffee, garlic, onions, chocolate, and meat are among the most commonly distorted foods. This happens because the recovering sensory cells fire in disorganized patterns, sending scrambled signals to the brain.
The more complex a food’s aroma profile, the more likely it is to trigger parosmia. The practical response is to simplify your meals. Blander, less aromatic foods with fewer ingredients are less likely to set off distortions. As you identify your specific triggers, whether certain foods, spices, or environmental smells, avoiding them reduces the frequency of unpleasant episodes. Eating food cold further limits the aromatic compounds that reach your nose.
Parosmia is actually a sign of recovery, not worsening. It typically means nerve pathways are reconnecting, just not perfectly yet. For most people it fades over weeks to months, though smell training can help the process along.
Medical Options for Persistent Cases
If taste and smell haven’t returned after several weeks, a few medical interventions have some evidence behind them.
Corticosteroid nasal sprays have shown the most consistent benefit in clinical studies. Research comparing different treatments found that certain steroid nasal sprays helped patients recover smell function roughly 23 days earlier than oral steroids or other nasal sprays. Combining a corticosteroid spray with daily smell training produced better results on standardized smell tests than smell training alone. These sprays work by reducing the inflammation in the nasal tissue that’s disrupting nerve function.
Zinc supplementation has also shown promise. In one trial of 105 patients with COVID-related smell loss, those taking zinc supplements recovered in a median of 7 days compared to 18 days in the group that didn’t take zinc. That’s a meaningful difference, though the study used a specific dose of 50 mg of elemental zinc twice daily, which is higher than what’s in a typical multivitamin and shouldn’t be taken long-term without guidance.
Neither treatment is a guaranteed fix, and steroid nasal sprays performed slightly better than zinc in head-to-head comparisons. But both are reasonable options to discuss with your doctor if home strategies aren’t producing results.
When Recovery Takes Longer Than Expected
Most taste and smell problems resolve within four weeks of a COVID infection. The WHO defines post-COVID olfactory dysfunction as impairment persisting beyond that four-week mark, which can include reduced function, distorted smells, phantom smells (perceiving odors that aren’t there), or a recently described phenomenon called “smell lock,” where a single odor persists and blocks the perception of others.
If you’re past the four-week mark with no improvement, or if your symptoms are getting worse rather than better, an ear, nose, and throat specialist can perform formal smell testing to assess how much function remains and rule out other causes. Persistent loss that predated COVID, for example, could point to a medication side effect or another underlying condition. The specialist may also be able to prescribe a targeted corticosteroid regimen or guide a more structured smell training program. The earlier you start smell training, the better your odds, so don’t wait months to begin.