Dr. Noam Sobel: How Smells Influence Our Hormones, Health & Behavior

The human sense of smell is incredibly sensitive and has the potential to be further enhanced through training, especially when other senses such as vision or hearing are absent.

When we meet someone, we unconsciously gather chemicals from their body, which we then apply to our own bodies to process information about that person. This phenomenon might explain why certain individuals become instantaneously close or "fast friends."

If a person loses their sense of smell for a period of 1-1.5 years, it becomes highly unlikely that they will ever regain it. This indicates that the olfactory system operates on a "use it or lose it" principle.

The loss of smell can serve as an early warning sign of neurological degeneration and diseases. It acts as an indicator, enabling early detection of these conditions.

Our nasal cycle, which determines the dominance of each nostril, constantly shifts. This cycle is driven by the sympathetic and parasympathetic nervous systems, impacting our olfactory experience.

The olfactory system is intricately linked to information processing and cognition. Our sense of smell plays a vital role in how we perceive and interpret the world around us.

We are continuously sensing our own odor clouds, which in turn influence our cognition and behavior. This process occurs whether we are consciously aware of it or not.

In our most basic behaviors, we tend to follow our nose rather than our eyes. For example, if a visually appealing food has an unpleasant smell, we are less likely to eat it. Similarly, we are more attracted to a potential romantic partner who smells pleasant, regardless of their physical appearance.

While the digitization of olfaction may have potential applications in medical diagnoses, such advancements are not expected to be realized in the near future.

Olfaction involves both the nose and the mouth. When it comes to food and taste, a significant portion of our olfactory experience is intertwined with our sense of taste.

As odor molecules travel up our nose, they interact with receptors lining the nasal structure, ultimately transforming into neural signals that our brain can interpret.

The significance of olfaction is underscored by the fact that a substantial portion of our genome is dedicated to this sense. Each receptor activation triggers a distinct subset of receptors, contributing to our ability to discern different smells.

A severe impact to the head can sever essential components of the olfactory system, resulting in partial or complete loss of smell. If the sense of smell is not regained within 1-1.5 years, recovery becomes highly unlikely.

Alpha lipoic acid has shown some potential in aiding smell recovery. However, the data supporting its effectiveness is mediocre at best.

Olfaction is not solely limited to the sense of smell; it also holds significant power beyond its primary function. It is strongly linked to the formation of memories, and encountering a smell for the first time often leads to particularly strong and enduring memory associations.

Humans possess the ability to follow scent trails, even when they are buried in the grass. This skill becomes particularly pronounced when our vision and other senses are deprived.

While humans have an innate remarkable sense of smell, it is also possible to improve and further train our olfactory abilities within a short span of just four days.

Our nasal cycle, which governs the alternating usage of our nostrils, is influenced by switches in the sympathetic and parasympathetic nervous systems. Interestingly, this cycle appears to be more closely tied to brain function rather than the specific demands of olfaction.

Olfaction is closely intertwined with information processing, cognition, and brain function. The act of inhaling scents through our nose plays a role in shaping how we process information and engage in cognitive tasks.

The loss of the sense of smell serves as a strong indicator of neurological diseases and neurodegeneration. Changes in olfactory function can manifest years before any other noticeable symptoms in conditions such as Parkinson's and Alzheimer's. However, the digitization of olfaction presents challenges in measuring and establishing causal links, as it has not been adequately developed for clinical testing and assessing deterioration without a baseline.