Ways to Regain Sense of Smell After COVID
Among the many consequences of the COVID-19 infection, one that has attracted much attention is the loss of smell or taste. For many, the condition is long-term and treatment remains elusive.
Why does this happen to some people and are there effective treatments available to restore our sense of smell after COVID?
Loss of smell is common with many viral infections
Our sense of taste and smell work together to help us enjoy food and drink. Losing these senses can make meals seem bland or bland. More importantly, we may not recognize potentially dangerous situations such as leaking gas or spoiled food.
Loss of taste (ageusia) and smell (anosmia) is not only an early symptom of COVID-19 infection—it is also a recognized symptom of late-onset COVID-19.
However, the condition is not unique to COVID.
“Loss of smell is common with many viral infections, and especially with COVID. In about 95 percent, the smell is back after 6 months,” Jacob Teitelbaum, MD, a board-certified internist and nationally recognized expert in the areas of chronic fatigue syndrome, fibromyalgia, sleep and pain, told The Epoch Times. .
In a study from New York University, researchers found that the presence of the COVID virus near nerve cells in the olfactory tissue stimulated an influx of immune cells, such as microglia and T cells to fight the infection.
These cells release proteins called cytokines that change genetic activity in the olfactory cells, even though the virus could not infect them. In other scenarios, immune cell activity dissipates quickly; but researchers theorize that the immune signaling associated with COVID proceeds in a way that impairs the activity of genes needed to build olfactory receptors.
Other research revealed why, for some people, loss is potentially permanent.
Scientists at Duke University, with experts from Harvard University and the University of California, San Diego, used a tissue biopsy (extracted sample) to analyze olfactory epithelial cells, specifically those from COVID patients with long-term anosmia.
The findings show that our immune cells can continue to respond, even when the threat is gone.
The analyzes revealed an extensive infiltration by T cells (immune cells) that caused an inflammatory response in the nose where the nerve cells for smell are located.
“The findings are surprising,” senior author Bradley Goldstein, MD, associate professor in Duke’s Department of Neurobiology, said in a statement.
“It’s almost like some kind of autoimmune-like process in the nose,” he noted.
In regaining our sense of smell, the steroid nasal spray shows promise
A study published in the American Journal of Otolaryngology found that fluticasone (Flonase) nasal spray helped participants regain their sense of smell.
Researchers looked at 120 people who experienced anosmia due to COVID-19 and divided them into two groups – one that received treatment and one that did not.
They found that smell and taste function improved significantly within a week in all the COVID-19 patients who received fluticasone nasal spray.
Teitelbaum said the nasal spray may work because viral infections can cause inflammation and swelling around the olfactory nerves. Fluticasone is an over-the-counter steroid nasal spray that reduces inflammation.
“Once the infection has cleared for a month,” Teitelbaum advised. “OTC Flonase Steroid Nasal Spray [used] for 6 to 8 weeks can reduce nasal and nerve swelling.”
But he cautioned that this nasal spray should not be used while symptoms of an active infection, such as a runny nose, are present.
Anosmia has been studied long before the current pandemic. A 2009 study found that the sense of smell can be re-sensitized in people who have lost the ability to detect smells.
Researchers exposed participants to one of four scents: clove, lemon, eucalyptus and rose.
Patients smelled the four intense odors twice a day for 12 weeks. They were tested for sensitivity before and after training using “Sniffin’ Sticks” of different odor intensities.
Compared to baseline, patients who trained their sense of smell experienced an increase in their sensitivity to odors, according to their Sniffin’ Sticks test score. Olfactory sensitivity was unchanged in patients who did not receive sensory training.
Research, looking specifically at people with COVID-related olfactory loss, found that olfactory training effectively improved their ability to detect smells.
“When started early and with good compliance, olfactory training was reported to be more beneficial in increasing olfactory function,” Teitelbaum said.
Vitamins that can help
There are many theories about what causes the loss of smell in COVID, but we still don’t know exactly why.
Teitelbaum believes it’s likely a mix of several causes, including low levels of certain nutrients, such as zinc.
“I give 25 to 50 mg [of zinc] a day for 6 months [to patients]”, he said.
Zinc is critical to immune function, with the key immune regulatory hormone called thymulin dependent on zinc. Many infections, including AIDS, deplete zinc to impair immunity. The smell is also dependent on zinc.
Another key nutrient for smell is vitamin A.
The retinol form of vitamin A in doses of 2500 to 5000 units per day, along with zinc can [at] “25 to 50 mg a day helps with smell over time,” Teitelbaum recommended.
However, pregnant women should be careful when taking this vitamin. “Vitamin A will cause birth defects in pregnant women at doses above 8,000 units,” Teitelbaum warned.
A case study from 2021 describes how a COVID-19 patient’s ability to smell was restored by olfactory training combined with daily doses of these B-complex vitamins:
5000 IU vitamin B1 100 mg vitamin B6 5000 mg vitamin B12
The patient’s anosmia improved significantly in 12 days and his sense of smell recovered by day 40.
George Citroner is a health reporter for The Epoch Times.