We all have bad breath every now and then, whether it’s because of poor oral hygiene, hunger, or the result of an onion-heavy meal. You can always brush your teeth or chew on a refreshing piece of gum, but if your bad breath isn’t going away, the smell can be an indication of an underlying health condition.

For instance, one specific odor could be due to liver disease, the Cleveland Clinic points out.

If your breath has a strong, musty smell—similar to rotten eggs and garlic—it can be a sign your liver is having difficulty filtering out toxins, an issue that likely stems from liver disease, Nancy Moyer, MD, wrote for Healthline. The condition, fetor hepaticus—which is nicknamed “breath of the dead”—is a result of toxic sulfur substances making their way into other parts of your body.

“When blood doesn’t pass easily through your liver, the toxic substances that would usually be filtered out by your liver make their way to other parts of your body, including your lungs,” Moyer explains. “When this happens, you might smell traces of these substances when you exhale.”

Liji Thomas, MD, describes it as having breath that is “sweetish, musty, and occasionally fecal in nature,” she wrote for News Medical.

It’s particularly important to be attune to something minor like this because “even in a stage of cirrhosis, the disease can be asymptomatic for many years,” according to the authors of a Belgian study published in the Journal of Chromatography B. They suggest that breath analysis might be helpful to detect liver disease.

You especially shouldn’t ignore your bad breath if it doesn’t go away with regular oral hygiene practices. If you’ve never been diagnosed with liver disease and suspect your musty breath is a warning sign, you should pay attention to other signals from your body, too. Other signs of liver disease can show up in the form of jaundice (yellowing eyes and skin), chronic fatigue, and abdominal pain, according to Chromatography Today. Healthline says bleeding easily, swollen legs, and confusion or disorientation are also symptoms to look out for.

To decipher whether something is wrong with your liver, see your doctor. They may conduct a blood test to see if your liver is functioning correctly. An ultrasound, CT scan, and liver biopsy are other ways to determine a liver problem. For other symptoms that could crop up, check out If You Notice This on Your Hands, Get Your Liver Checked, Doctors Say.

A 2016 study, led by the University of Birmingham in the U.K. and published in the journal EBioMedicine, suggests elevated levels of limonene—a natural compound found in fruits and vegetables—in the breath could be an early sign of liver disease and could result in the odor. Margaret O’Hara, MD, a lead investigator in the study, said high levels of limonene are associated with liver disease, likely because the vital organ cannot fully metabolize the compound.

“If our further research is successful, in the future we can envisage a small portable breath analyser that can be used by GPs and other health professionals to screen for early-stage liver disease, leading to earlier treatment and better survival rates,” O’Hara said. Chris Mayhew, MD, a senior author of the study, said the findings could lead to a possible “noninvasive, real-time detection of early-stage liver disease.”

It’s difficult to eliminate bad breath if it derives from a type of liver disease, but Mayhew suggests you could decelerate additional liver damage with lifestyle changes and medicine if it’s caught early.

In addition to seeking medical advice from your doctor, experts suggest not drinking alcohol, consuming less salt, and exercising often if your liver isn’t healthy. And for more up-to-date health advice, check out If You Take These 2 OTC Meds Together, You’re Putting Your Liver at Risk.