Why do you lose taste with COVID?

Naturopathic doctors remind patients to get help for the common symptoms of losing taste and smell from viruses and that it can be treated with aromatherapy and taste therapy.

Why do some people experience loss of taste and smell from COVID-19? And why does it cause brain fog? Researchers at NYU Grossman School of Medicine and Columbia University say these two common symptoms of the COVID-19 virus may be related.

Why do you lose taste with COVID?
COVID-19 may cause a loss of taste because of an inflammatory reaction in the nose (not the mouth).

Losing taste is one of the most commonly reported symptoms and often occurs before other tell-tale symptoms. Women experience it more than men and there may be a genetic component associated with the symptom, according to the journal Nature.

At the start of the pandemic, Dr. Tina Kaczor, naturopathic doctor and editor-in-chief of Natural Medicine Journal said in an interview that 30% to 70% of people with COVID-19 reported losing their sense of taste and smell. She added, … “I think what’s really interesting about this is it’s not unique to coronavirus, let’s just be clear, this can happen with the flu, so it’s not a very sensitive test. Forty percent of all cases of loss of smell that present to the doctor are due to a viral infection of some sort. So that could be some other viral infection that affects the nasal passages, so it’s not unique to Covid. So I just want to be really clear about that. People who are catching the flu out there might also lose sense of smell, but it is also, given this pandemic that we’re going through, it’s an early symptom in people who have no other symptoms. …”

However, what exactly leads to this strange and annoying symptom has been unclear until this new study in the journal Cell. While you may think it’s all about the tongue, it looks as if infection from the CARS-CoV-2 virus “indirectly dials down the action of olfactory receptors (OR)” in the nose. Loss of taste is directly linked to smell. These receptors are proteins on the surfaces of nerve cells in the nose (not the mouth), which detect the molecules associated with odors.

The scientists found that the presence of the virus near nerve cells (neurons) in olfactory tissue in the nose caused a dramatic rush of immune cells, microglia and T cells that sense and counter infection. The cells release proteins called cytokines – which change the genetic activity of olfactory nerve cells – even though the virus does not actually infect them. In normal cases (the pandemic is anything but normal), immune cell activity would stop quickly in the brain. However, with COVID-19 the immune signaling continues in just the right way to reduce the activity of genes needed for building olfactory receptors.

Certain DNA sections in the nose become less accessible to cell’s normal gene reading machinery and signaling. The loss of taste and smell are not just early signs of COVID-19, but it also shows how the virus may affect the brain and cause brain fog. Neurons in the nose are wired to sensitive areas of the brain, so when immune cells in the nasal cavity overreact, it may affect emotions and one’s ability to thinks clearly, which is a common problem with long COVID.

“The realization that the sense of smell relies on ‘fragile’ genomic interactions between chromosomes has important implications,” says co-corresponding author Benjamin tenOever, PhD, professor in the Department of Microbiology at NYU Langone Health. “If olfactory gene expression ceases every time the immune system responds in certain ways that disrupts inter-chromosomal contacts, then the lost sense of smell may act as the “canary in the coalmine,” providing any early signals that the COVID-19 virus is damaging brain tissue before other symptoms present, and suggesting new ways to treat it.”

How long can a loss of taste and smell last and should it be treated?

We’ve all had a cold, a stuffy nose or the flu that takes away our sense of smell and taste. The COVID-19 virus is unique in that you may not have a runny nose but still have a loss of smell and taste. It can last for a few weeks, but for about 12% of reported cases, normal smell and taste have not returned since being infected.

Why do you lose taste with COVID?

Doctors say patients may not get help after noticing that they have lost their sense of smell and taste, thinking it will eventually improve. Some people may regain some sense of smell or taste, but it may not be the same as before the infection. Don’t ignore this. It is important to see a doctor to rule out any other causes of the dysfunction and to restore these important sensory functions.

There are ways to restore smell through aromatherapy smell training. Smell training is a simple, no side-effect treatment for post viral loss of smell. It involves sniffing at least four different odors twice a day for several months. The smelling kits contain aromatherapy oils in just the right strength , sich as eucalyptus, lemon, rose, cinnamon, chocolate, coffee, lavender, honey, strawberry and thyme. Studies show that after six months of retraining the olfactory system people restored their sense of smell.

Taste training is another useful treatment. Trained physicians may use a combination of therapies including reducing anti-inflammation and reintroducing basic types of taste and textures through candies and/or chewing gums, as well as other savory flavors like umami with foods.

If you need help with restoring your smell and taste after a COVID-19 infection or other respiratory tract infection, contact a naturopathic doctor for support and guidance. You can find a naturopathic doctor here with INM’s Find an ND Directory.

For more information in naturopathic approaches to long COVID, see the Institute for Natural Medicine’s article, What is Long-Haul COVID? How Naturopathic Medicine Can Help Relieve the Suffering, by Michelle Simon, ND and Amy Rothenberg, ND.


This article is provided by the Institute for Natural Medicine, a non-profit 501(c)(3) organization, partnered with the American Association of Naturopathic Physicians. INM’s mission is to transform healthcare in America by increasing both public awareness of naturopathic medicine and access to naturopathic doctors for patients. INM believes that naturopathic medicine, with its unique principles and practices, has the potential to reverse the tide of chronic illness that overwhelms existing health care systems and to empower people to achieve and maintain their optimal lifelong health. INM strives to achieve this mission through the following  initiatives:

  • Education – Reveal the unique benefits and outcomes of naturopathic medicine
  • Access – Connect patients to licensed naturopathic doctors
  • Research – Expand quality research of this complex and comprehensive system of medicine

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