Can You Actually Smell Sickness?
Body Odor And Health
Did you know that the scent emitted by a person may be one of the first major clues to certain diseases? For centuries, our sense of smell has been used as a diagnostic tool in the practice of medicine. Body scent has been used way back as 2000 BC by ancient Greek and Chinese to detect infectious diseases such as tuberculosis. Keele (1963) explains how almost 2000 years ago Susruta Samhita, one of the fathers of ancient Indian medicine, stated, “by the sense of smell we can recognize the peculiar perspiration of many diseases, which has an important bearing on their identification.”1
A person’s body smell (emanating not just from the skin but the breath, blood, urine and other bodily fluids) can reveal a lot about his or her health and can be used to identify sickness to a certain extent. According to a Swedish research study by Olsson et al, humans may actually be able to smell sickness or at least detect a distinct odor in people by virtue of highly active immune systems that respond to infection. Our bodies may instinctively know what we smell, even if we are not able to categorize or define it consciously.2 3
Illnesses and Their Characteristic Smell
Research suggests that certain illnesses actually have a unique odor.
- Schizophrenia and several rare inborn errors of metabolism (IEMs) caused by enzyme deficiencies are linked with a distinctive body odor.
- Scrofula is a kind of tuberculosis infection that is associated with a stale beer smell.
- Yellow fever can cause a raw meat smell, often reminiscent of the butcher shop.
- Skin conditions such as vagabond’s disease, pemphigus, infected eczema, herpes labialis, and herpes zoster are associated with an unpleasant smell.
- Syphilis can cause a strong fishy smell.
- Darier’s disease can produce an unpleasant smell as a result of the abnormalities in the keratin genes.
- Diabetic ketosis imparts a fruity aroma like that of decomposing apples. This is usually attributed to the smell of the ketones on the patient’s breath. The sweat also has a characteristic odor.
- People with typhoid are said to emit a smell comparable to that of freshly baked brown bread.
- Gingivitis, tonsillitis, and Vincent’s angina can cause a rotten smell in the breath.
- People with diphtheria have a sweetish odor.
- A urine-like odor is found in the breath of people suffering from uremia. This is called uremic fetor and is triggered by the production of ammonia in the saliva.
- Osteomyelitis causes a fetid odor.
- Diseases of the respiratory tract such as bronchiectasis, lung abscesses, and ozena are associated with unpleasant smells.4 5 6
How is Body Smell Linked to Sickness?
Disease causes chemical changes in the body or alterations in metabolism, accompanied by the production of different metabolic compounds. These modifications in body chemistry result in different body odors. In the Swedish study, to some extent the association between smell and immune activation was linked to the increased level of cytokines. That is, the greater a participant’s immune response, the more unpleasant their odor. These results strongly support the belief that humans emit a chemical cue as part of the sickness response and this can be perceived by others.7 8 9
Body odor may in some cases be merely physiological and can be linked to poor personal hygiene or odor generating foods such as garlic. However, there are grounds to believe that in some instances it can be pathological and connected to a disease of the body. The ability to detect these smells could help us address or avoid potentially dangerous illnesses, serving both as a diagnostic tool or as the first line of defense to protect healthy individuals. It may even help us understand how infectious diseases can be contained. Ongoing research on smell diagnoses, electronic noses, and “super smellers” like dogs is an exciting step in the right direction.
References [ + ]
|1.||↑||Keele, Kenneth David. The evolution of clinical methods in medicine. Thomas, 1963.|
|2, 6.||↑||Liddell, K. “Smell as a diagnostic marker.”Postgraduate medical journal 52, no. 605 (1976): 136-138.|
|3, 4, 9.||↑||Olsson, Mats J., Johan N. Lundström, Bruce A. Kimball, Amy R. Gordon, Bianka Karshikoff, Nishteman Hosseini, Kimmo Sorjonen et al. “The scent of disease human body odor contains an early chemosensory cue of sickness.”Psychological science (2014): 0956797613515681.|
|5.||↑||Joanne M. Bargman, Karl Skorecki (2011), “Chapter 274. Chronic Kidney Disease”, in Anthony S. Fauci, Eugene Braunwald, Dennis L. Kasper, Stephen L. Hauser, Dan L. Longo, J. Larry Jameson, and Joseph Loscalzo, Harrison’s Principles of Internal Medicine (18 ed.), McGraw-Hill,ISBN 978-0071748896|
|7.||↑||Detecting Sickness By Smell, Association for Psychological Science.|
|8.||↑||Bijland, L. R., M. K. Bomers, and Y. M. Smulders. “Smelling the diagnosis: a review on the use of scent in diagnosing disease.” The Netherlands journal of medicine 71, no. 6 (2012): 300-307.|