6 Reasons Your Breath Reeks—Other Than Bad Hygiene. If brushing your teeth isn’t doing the trick, your body might be trying to tell you something
You brush, floss, and rinse with mouthwash a couple times a day, avoid garlic bread on a first date, and always pop a mint after your morning coffee—yet somehow your breath still stinks. What gives?
Poor oral hygiene is not the most common cause of bad breath, says Harold Katz, D.D.S., bacteriologist, and founder of the California Breath Clinics. Most chronic bad breath is actually due to dry mouth: When you don’t have enough moisture, the bacteria that live in your mouth thrive.
“When you sleep at night there’s little or no saliva production,” explains Dr. Katz. “That’s what causes dryness and morning breath.”
If your only issue is morning breath, just brush your teeth. But if you’re dealing with dry mouth (and the accompanying bad odor) that lingers all day, it could be caused by a medication you’re taking.
“Seventy-five percent of prescription drugs, including antidepressants, antihistamines, and blood pressure drugs, have dry mouth as a side effect,” says Dr. Katz.
So if you find people frequently backing away when you’re talking, ask your doc if your meds might be to blame. If so, sipping more water, chewing sugarless gum, or maybe switching to a different drug could help.
In other instances, chronic bad breath could signal that something is amiss elsewhere in your body. These scents may provide clues that can help your doctor or dentist figure out what’s wrong.
You might have allergies, post-nasal drip, or a sinus infection. When you have chronic sinus issues, the bacteria in your mouth can convert the proteins in mucus into a stinky compound called skatole.
Taking allergy medication or (if your doctor determines you have a bacterial infection) starting antibiotics should help.
WHAT IT MEANS IF YOUR BREATH SMELLS FRUITY
You might have diabetes. Sugar in your bloodstream normally heads into your cells, where it’s used for energy.
If that doesn’t happen, your blood sugar rises, and your cells start burning fat for energy. The byproduct of that process is ketones, which can make your breath smell fruity, says Shilpi Agarwal, M.D., a family medicine doctor and integrative medicine physician in Washington, D.C.
“If I noticed that in a patient, I would test his blood sugar,” to see if he’s developed diabetes, says Dr. Agarwal.
WHAT IT MEANS IF YOUR BREATH SMELLS LIKE SOUR MILK
You might be lactose intolerant. This odor could indicate that you’re not breaking down the protein in dairy proteins properly, says Dr. Katz.
Of course, you’ll also likely have other symptoms, such as diarrhea, cramps, and gas after consuming milk products.
WHAT IT MEANS IF YOUR BREATH SMELLS LIKE A DIRTY DIAPER
You might have a tonsil stone. Bacteria and debris can get stuck in your tonsils and form a visible “stone” in the crevices.
“It’s really rotten, like a dirty diaper,” says Dr. Agarwal, who says that your primary care doctor can probably remove the offending particle with a swab or forceps.
WHAT IT MEANS IF YOUR BREATH SMELLS LIKE SOMETHING IS ROTTING
You might have a lung disease. A very foul odor—“much worse than traditional bad breath,” says Dr. Katz—could be a sign of a lung problem ranging from an infection (like pneumonia) to cancer.
Interestingly, breath tests designed to identify the odors associated with cancer are currently in the works.
If you suspect you might have any problem with your lungs, see your doctor for an exam. After listening with a stethoscope, she might refer you for blood work, a chest X-ray, or other tests.