Breath Odor Can Be a Sign of Disease, What?

Illustration of bad breath (istockphoto)

JAKARTA - Breath odor can be a sign of diseases that have attacked the body. This is reiterated through a study entitled "The Gut Microbiota Shapes the Human and Murine Breath Volatilome".

In the study, it was found that human breath contains volatile organic compounds derived from gut microbes. These compounds can be a clue for scientists about the condition of the gut microbiome, body metabolism, and ultimately the overall health of a person.

"Compounds in breath contain important information about health, and some of those compounds come from microbes in the gut," said Division Chief of Infectious Diseases at The Children's Hospital of Philadelphia, Audrey R. Odom John, M.D,Ph.D, quoted from Prevention, on Monday, February 2, 2026.

The following are some diseases that can be recognized from the smell of breath.

1. Type 1 and type 2 diabetes

Both type 1 and type 2 diabetes can be detected by the patient's breath. This is because diabetes makes the breath smell of ketones, a chemical produced by the liver when the body breaks down fat and can cause a sweet breath like fruit or acetone.

"Historically, breath odor has been used to diagnose conditions such as diabetes because of the presence of a characteristic odor of ketones," said John.

2. Diseases in the liver

A different breath odor can also indicate that there has been damage to the liver. Known as hepatic odor, this condition produces a characteristic musty odor that indicates liver disease or severe liver dysfunction.

3. Dry mouth

Dry mouth or xerostomia occurs due to lack of saliva production. This condition can make bacteria and food debris not rinsed properly, which causes bad breath.

4. GERD

Gastroesophageal reflux disease or GERD can make bad breath tend to be acidic or rotten. This is caused by the rise of gastric fluid into the esophagus which is a symptom of GERD relapse.

If the breath odor occurs continuously, and does not disappear after brushing your teeth, cleaning your tongue, or maintaining oral hygiene, it is recommended to see a doctor.

Other warning signs that require immediate medical attention include fishy/ammonia breath, bad smell, extreme dry mouth, bleeding gums, toothache, or pain when swallowing.