BrainStuff Season 5 Episode 2 Does Disease Have A Smell?

In BrainStuff season 5 episode 2, titled "Does Disease Have A Smell?," the hosts explore whether diseases have a distinguishable odor. Beginning with a brief history of the long-standing belief that diseases carry specific smells, the episode delves into the science behind odor detection and the complexities of identifying distinct scents associated with illnesses.

The episode starts by citing earlier practices in history that aimed to recognize medical conditions through smell. In medieval times, physicians would rely on their sense of smell to diagnose patients, often observing scents, color, and consistency of bodily fluids or excreta. Similarly, ancient healers in China and India would pay attention to the scent of a patient's breath, urine, and feces to identify the source of an illness.

However, the notion of identifying disease by smell was diminished with the progress of technology and scientific advancements, leading to more precise methods of diagnosis. Yet, there remains anecdotal evidence of people detecting specific scents from individuals carrying certain conditions, such as diabetes, tuberculosis, or even Parkinson's disease.

Several studies have suggested that dogs can detect illnesses like cancer, malaria, diabetes, and bacterial infections by smelling the VOCs or volatile organic compounds produced by the infected cells. Specialized equipment like GC-MS (gas chromatography–mass spectrometry) or eNose (electronic nose) can also detect such compounds and differentiate between healthy and pathogenic samples.

The hosts caution the audience against relying solely on smell to diagnose diseases, stressing the importance of proper medical diagnosis and treatment. While an individual may indeed produce a unique odor due to their health condition, many other factors besides diseases can influence body odor, making the scent unreliable on its own.

Additionally, the hosts explore the cultural and emotional aspects of smelling sickness. People often avoid smells they associate with illness, such as vomit, feces, or death, and associate them with disgust and anxiety. They discuss a phenomenon called "olfactory-evoked nostalgia" or the power of scents to trigger emotional memories, which can create a positive or negative association with smells over time.

The episode concludes by summing up the complexities of identifying scents associated with specific diseases and emphasizes the importance of using technology and scientific methods to diagnose and treat medical conditions. It also highlights the need to understand the cultural and emotional aspects of smells and their impact on our psychological well-being. Overall, "Does Disease Have A Smell?" is an educational and thought-provoking episode that sheds light on the relationship between smell and our health.