In a recent interview, Prof. Noam Sobel from the Weizmann Institute of Science discussed his groundbreaking research on the differences in breathing patterns between individuals with a sense of smell and those with congenital anosmia—people born without the ability to smell. The findings suggest that the ability to perceive odors may influence not only the way we breathe but potentially our overall health.
Sobel highlighted the paradox surrounding the sense of smell, which has often been underestimated in importance. He referenced historical perspectives, including Charles Darwin’s assertion that smell was “of extremely slight service” to humans. Yet, numerous studies have linked the loss of this sense to significant issues such as depression, social isolation, and even a higher risk of early mortality. “There’s this notion that this sense is completely unimportant, and yet if you lose it, a lot of negative consequences arise. So it seems like a paradox,” he explained.
This sensitivity to smell has garnered more attention recently due to its prevalence as a symptom of Covid-19. Sobel and his research team set out to unravel this complex relationship by studying 21 individuals with congenital anosmia alongside 31 individuals with an unaffected sense of smell. Participants were equipped with devices that measured airflow while they went about their daily lives.
Their analysis revealed intriguing results: individuals with a functioning sense of smell tended to sniff more frequently than those with anosmia. The researchers proposed that this increased sniffling could be a natural response to environmental odors. They further confirmed this hypothesis through an additional experiment, which showed that those with a sense of smell did not exhibit extra sniffs in an odor-free environment.
Interestingly, the team found that while awake, individuals with anosmia displayed more pauses in their breathing and had a lower peak airflow when exhaling. They also noted variations in respiratory patterns during sleep, a state where surrounding odors typically remain constant.
Utilizing machine learning, the researchers developed an algorithm capable of predicting the presence of anosmia with an accuracy rate of 83%. However, Sobel acknowledged the study’s limitations, including its small sample size and the potential oversight of mouth breathing—factors that might influence results. The current research solely focused on individuals born without the sense of smell, though Sobel mentioned ongoing studies involving those who lost their sense later in life.
While the findings do not definitively establish that altered breathing patterns cause health issues in individuals with anosmia, they do suggest a possible connection that could affect both physical and mental well-being, particularly through changes in brain activity. Sobel summed it up: “If you don’t sigh, you die. So the notion that patterns of respiration can be really influential is not all that far-fetched.”