The recent warning from the Food and Drug Administration (FDA) that a widely used homeopathic cold remedy, Zicam, can destroy one's sense of smell has alarmed many consumers who have used the product.
At least 130 Zicam users, according to the FDA, have reported a loss of smell after using the zinc-based nasal gel or swabs produced by Matrixx Initiatives Inc. The company, which has defended the safety of its medication, has begun a recall.
The Zicam warning has raised the profile of an issue that rarely receives attention: scent loss. The news prompted thousands of people affected by anosmia -- the total or partial loss of the sense of smell -- to tell their stories. And the one message they all share is that the sense of smell is more important than many people understand.
Firsthand knowledge
I lost my own sense of smell in August 2005. It didn't vanish due to a puff of medication, or in the aftermath of a cold. I lost my sense of smell as I jogged near my home in Boston and was hit by a car. My skull smashed against the windshield and the olfactory neurons -- delicate fibers running from the nose toward the brain -- were sheared in the impact. In one instant, my perception of the world changed. I soon learned the devastation of such loss.
Intangible and often ephemeral, the ability to smell is easily ignored and often forgotten in the face of vision, hearing and touch. Without scent, however, one's experience of the world is dimmed. Flavor is reduced to the salty, sweet, bitter and sour of the taste buds. Food, therefore, is nothing but texture and temperature. Coffee is a hot bitter water; milk, thick and gummy. Bakeries are indistinguishable from locker rooms.
The sense of smell is powerful and transportive, and it links to many other aspects of perception. Olfactory processing is connected to the limbic system of the brain, areas responsible for memory and emotion. Smell ties to recognition: It has been shown that mothers can recognize their newborn babies by scent alone just hours after birth. It ties to sex: Though theories on pheromones are disputed, you'd be hard-pressed to find someone who didn't enjoy the scent of the crook of a lover's neck.
I have spent time with many who have lost their sense of smell in the process of reporting my own book on the subject. For a great many, the cause remains a mystery. But everyone feels the effects.
Studies have shown anosmics report trouble cooking and eating, struggling with mood changes and feelings of safety. "When the sense of smell is lost," writes Thomas Hummel and Steven Nordin in the introduction to Quality of Life in Olfactory Dysfunction, "it is not just that it becomes a difficult task to differentiate between cardboard and a hamburger, but also a sense is lost which alerts us to dangers from fire or rotten food."
Complicates life
I met Debbie Bondulic, a photography agent in New York City who lost her sense of smell because of a sinus condition. She told me that without the scent of fresh-baked bread or coffee, she felt incomplete. "I would walk into a bakery and not know where I was," she said.
I spoke with Andy French, a music marketer in Los Angeles who lost his smell for 10 years before it mysteriously returned. Without scent, he felt paranoid about keeping himself and his clothes clean, and he realized the importance of smell in attraction and dating.
"Everything in life has these cues and then they were taken away," he said. "It made everyday life more complicated."
While some types of sinus disease are treatable, for most of those who suffer from anosmia, there isn't much one can do to recover but wait and see.
"Clinics have established what the primary causes are and what the various ways to test it are," said Beverly Cowart, director of the Monell-Jefferson Taste & Smell Clinic in Philadelphia, "but there's still a very limited amount that we can do to help."
The possibility of recovery depends mainly on the degree of loss, the length of time scent has been gone, and age. It can return in an instant or seep back gradually over years.
Cowart generally gives at least a two-year window for her patients to see improvement before hope begins to fade. One thing that many doctors suggest to do in the meantime is simple: practice smelling.
I am fortunate because I have regained most of my sense of smell. It came back largely through luck. The olfactory neurons are capable of regeneration, and mine have slowly healed and reconnected over the past four years. Others are not so lucky.
So take a moment to stop and enjoy the scent of your coffee, your girlfriend's perfume, your child's hair. It's important to know what you have. Anything can change in an instant.
Molly Birnbaum is a freelance journalist in New York City whose book on losing and regaining her sense of smell is scheduled to be published in 2011.
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