10 things your dentist can tell about your health just by looking in your mouth

When dentists peer into your mouth, they don’t just see how well you’ve been brushing and whether you’ve really been flossing. Your mouth, as it turns out, can be a window into your overall health.

Roughly 100 conditions have warning signs and symptoms that manifest in the mouth, estimates Dr. Kami Hoss, a California-based orthodontist and founder of Howard Healthcare Academy, a higher education institute dedicated to teaching those in the dental field.

“In fact,” he says, “sometimes early signs of many of illnesses first appear in the mouth.”

For example, gingivitis — or inflamed gums — can be caused by poor oral hygiene, poor diet or smoking. But as Hoss explains, it can also be a sign of other more serious underlying conditions, such as leukemia or HIV.

Below, dentists share what medical problems they spot during exams and explain what they recommend patients do.

1. Diabetes

While dentists can’t diagnose diabetes, they can pick up on ketosis breath, a uniquely sweet odor caused by the body’s overproduction of ketones.

Acetone (yes, the same chemical that removes nail polish) is the ketone that produces the sweet pungent smell, explains Dr. Jennifer Silver, a dentist based in Calgary, Canada. If Silver notices this smell on a patient, she’ll ask them if they’ve had blood work done recently and, if not, recommend they do so because their breath hints at an overproduction of ketones.

Silver shares that, upon mentioning this to one of her patients during an exam, he began her about other symptoms that could indicate diabetes.

“It turns out he was experiencing just about all the symptoms and didn’t know why and his wife had even told him his breath had an unusual odor,” says Silver.

Her patient ended up making a doctor’s appointment and discovering that he did, in fact, have diabetes.


2. Squamous Cell Carcinoma

Squamous cell carcinoma, which is the second most common type of skin cancer, can show up first as a simple fever blister that doesn’t heal, explains Dr. Linda Edgar, a former Academy of General Dentistry National President with Meridian Dental Clinic in Washington.

“Dentists always look in the mouth for any changes from normal,” says Edgar.

If something is concerning, she explains, they typically refer the patient to a physician for a blood test or biopsy to determine if cancer is present.

“I have referred over 10 people for abnormalities whose lives have probably been saved because we looked,” she says.

Health Care Divides New German Coalition
Getty Images | Sean Gallup

3. Leukemia

Changes in the tongue, such as swelling or excess redness, can potentially be caused by other diseases like leukemia, Edgar says. Again, if your dentist notices these changes, he or she may refer you to a physician for testing.

Since leukemia affects the body’s infection-fighting cells, a patient with this type of cancer might develop infections like a sore throat or bronchial pneumonia, and mouth sores or skin rashes could accompany the infection, according to the Cleveland Clinic.


4. Sleep Apnea And Snoring

People who snore or have sleep apnea tend to have a higher incidence of teeth grinding, says Dr. Jason Hui, a family and cosmetic dentist based in Texas. People who grind their teeth generally have shorter and flatter teeth, and their teeth tend to be more yellow, gray or discolored, Hui says.

Many of Hui’s dental patients have shown signs of sleep apnea, a serious condition that can lead to other health problems, such as heart disease and diabetes. Hui says that when he suspects a patient might have problems with sleep apnea, he asks if they have problems falling asleep or staying asleep, if they experience excessive sleepiness during the day or if they don’t feel refreshed after a night’s sleep. If they’ve experienced any of these symptoms, he refers them to a sleep specialist for testing.


5. Oral Cancer

In most cases, oral cancer appears as red and white lesions on the floor of your mouth, palate or tongue, explains Dr. Steven DeLisle, a Las Vegas-based children’s dentist. If he sees these symptoms, he advises patients to see an oral surgeon or a medical doctor for a biopsy.

DeLisle once had a patient come in for a consultation for dentures and, when he looked in her mouth, he noticed an abnormal lesion. She had an oral surgeon complete a biopsy, which came back positive for cancer.

“It was caught early and she had treatment to take care of it,” he says.


6. Nutritional Deficiencies

The mouth can hint at mini nutritional deficiencies, says Dr. Sanda Moldovan, a periodontist and nutritionist. A glossy red tongue can be a sign of an iron deficiency while bleeding red gums and the absence of tartar might mean a vitamin C deficiency, a sign that the patient might not be eating enough fresh fruits and vegetables.


7. Gluten Intolerance

Canker sores can sometimes be a sign of gluten intolerance, Moldovan says.

“I would recommend an elimination diet for a month to see if they reoccur,” she says. Or, conversely, patients could get a cheek swab for testing.

Study Links Ultra Processed Foods To Cancer
Getty Images | Dan Kitwood

8. Gastroesophageal Reflux Disease Or GERD

In the course of a routine exam, dentists might see tooth erosion, which can be a symptom of GERD, a type of acid reflux, explains North Carolina-based Dr. Bobbi Stanley. Dentists, she says, will recommend a visit to a general practitioner or a GI specialist for treatment, which might include a proton pump inhibitor to block the production of acid.


9. Anemia

Anemia is a condition that develops when your blood doesn’t have enough healthy red blood cells or hemoglobin. It can cause a patient’s mouth to be red and have a burning sensation, explains Dr. Angela Abernathy, a restorative and cosmetic dentist in New York City.

“Also, the gums can be swollen, have a glossy appearance and bleed easily,” she says.

If she notices these symptoms, she advises her patients to visit their physician and have blood tests done so they can start care as soon as possible.


10. Headaches Near Your Temple

Do you have jaw pain and headaches that are centered near your temple? Do you feel soreness or tiredness in the jaw after eating or talking at length? This could have to do with an imbalanced bite that’s forcing the jaw muscles to work harder, explains Maine dentist Dr. Ben Lawlor.

Those with an imbalanced bite can have badly worn down teeth, uneven teeth, top teeth that are angled back so they trap the lower jaw, or even missing teeth that were cracked and had to be removed. Every bite for someone with this condition requires around ten times more work from the muscles, which leads to extreme muscle fatigue and eventually pain.

There are several ways to correct the imbalance.

“At the simplest level, we can manage their bite with an inexpensive bite guard or we can correct the imbalance with Invisalign, crowns or veneers,” he says.


Did you know your dentist could tell so much about your general health by looking into your mouth?