Smell Loss Is One Symptom Of COVID-19 That Essential Oils Might Ease

Zara Patel, M.D., an associate professor otolaryngology-head and neck surgery (ENT) at Stanford, has been helping patients regain their sense of smell for years. She tells mbg that post-viral olfactory loss1—a condition where one's sense of smell is damaged following an illness—is actually relatively common, though not as much attention was paid to it until the CDC named loss of smell a possible symptom of COVID-192.

Temporarily losing your ability to smell when you have a virus is normal, but sometimes this symptom can linger even after the rest of your body recovers. Patel says that age and pre-existing conditions play a role in how likely you are to develop post-viral olfactory loss—as does the aggressiveness of your virus. It's still too early to say how likely the coronavirus is to cause long-term smell issues. However, if you, or someone you know, has recovered from the disease but still struggle to catch a whiff of your favorite scent, it's something you should take seriously.

Olfactory training, the process of regularly and repeatedly smelling certain things, is one approach that can help your sense of smell return. Interestingly enough, sniffing something like perfume or coffee does not benefit smell—and can actually do more harm than good. Since these contain many different types of odors, smelling them may confuse your olfactory neurons even more and cause you to associate them with unpleasantly metallic or chemical odors.

One accessible tool that does seem to be helpful for olfactory training? Essential oils. In one 2017 clinical trial, Patel and a team of researchers found that patients who "smell trained" with essential oils were twice as likely to improve their sense of smell3 than those who did not. This is because essential oils tend to have one distinct odor molecule. Smelling them can be a way to focus your attention on what that specific scent used to mean for you and what sorts of memories it drums up.

"What we're doing by using the essential oils in olfactory training is using the memory of them as a pathway—a sort of map through which the correct synaptic connection can be made again," Patel explains.

Since the olfactory nerve is unique in the way it travels directly through the memory center of the brain, smells have a special way of evoking of memory. When you smell oils from a variety of families—floral, fruity, aromatic, and resinous are some biggies—you are stimulating multiple facets of odor to come back.