It’s been long known that bad breath may be a symptom of oral conditions such as gum disease, but it can reveal much more than mouth issues. When infections, harmful bacteria and other toxins exist in the body, they can create a pungent smell in the mouth. For health care professionals, that abnormal scent is a warning sign that you might have a medical condition. In fact, physicians have been smelling patients’ breath (as well as their bodily fluids) throughout history to help diagnose illnesses – yellow fever, for instance, causes the saliva to smell like a butcher’s shop.
These bad breath smells are often too subtle for the human nose to detect; however, new advancements in biomedical technology may provide a solution. According to BBC News, scientists are developing odor-sniffing machines that can catch these very light scents to aid in diagnosis and treatment. In fact, in early March, researchers found an odor-sniffing machine that can detect breast cancer as effectively as mammograms (it smells like rotting or decay), and they’re hopeful that many other similar instruments for various diseases are in the works.
A 2011 article in the journal Sensors looked into these “electronic nose” applications and revealed just what bad breath and other offensive odors reveal when it comes to disease and illness. If one’s breath resembles acetone (or nail polish remover), it could be a sign of diabetes. That’s because when your body is low on glucose, it must begin burning fat for energy. This causes an excess of ketones in the liver and blood, and one of these ketones is acetone. Many refer to it as a “fruity” scent.
Additionally, while chowing down on seafood may be among bad breath causes, those whose saliva has an odor of raw fish may in fact have liver failure. This oral cavity scent is known as uremic fetor and is the effect of an excessive amount of urea in the body that breaks down into ammonia. It’s especially important for someone experiencing fishy mouth to see their health care professional – liver damage is a sneaky condition that can go undetected until the organ loses nearly all of its function and the damage is irreversible.
The report also described other bad scents found on the body that can be warning signs of illness. The odor of rotten apples on the skin can mean an anaerobic infection, while a hint of ammonia in the urine may mean a bladder infection. There are some more unusual skin smells on the list, such as the scent of freshly plucked feathers as a sign of rubella, the stench of stale beer for scrofula (a tuberculosis infection in the lymph nodes) and the smell of freshly baked bread to signify typhoid. Additionally, if someone’s sweat stinks slightly of vinegar, it could be a sign of schizophrenia.