How Bad Is It to Brush Your Teeth Only Once a Day?

Updated: Jul. 12, 2022

Here's what happens to your mouth, teeth, and gums—beyond stinky morning breath—when you miss one of the two daily recommended brushings.

Think of your toothbrush, floss, and mouth rinse as the good guys of oral health care. The bad guys are bacteria. “Bacteria thrive on food left on or in between teeth, and it grows at lightning speed,” says Lee Gause, DDS, of Smile Design Manhattan in New York, NY. “If you only brush once a day, plaque and bacteria build up in the mouth and lead to bad breath, tooth decay, and gum disease.” Of course, bad breath is just a minor misdemeanor compared to the real crime of what happens when you don’t brush your teeth twice a day.

8 Ways You’ve Been Brushing Your Teeth All Wrong

How a buildup of bacteria leads to cavities

What happens when you don’t brush your teeth? Picture millions of bacteria trespassing on (and in between) your teeth and gums. Whenever you eat foods or drinks with sugar in them, it leaves a sticky film of bacteria, called plaque. The bacteria in plaque creates acids that attack tooth enamel, and eventually the enamel breaks down, causing a little hole in the tooth, called a cavity.

It doesn’t stop there. The bad guys of bacteria are a hardy bunch. “Brushing alone misses 75 percent of your mouth, leaving millions of germs behind,” says Gause. A three-step defense will protect your teeth and gums. “I recommend brushing, flossing, and swishing with an antiseptic mouth rinse like Listerine twice a day.” Flossing helps remove food particles, but Gause says mouth rinse can help clear out hard to reach areas and penetrate plaque to break down its structure. (In the meantime, don’t believe these 6 myths about mouthwash that might be hurting your health.)

Besides cavities, brushing your teeth just once a day to can lead to other serious offenses, including gingivitis, the milder form of periodontal disease. It causes havoc on your gums, leaving them red and swollen, not to mention the bleeding that you may see when you spit during brushing. With good behavior (professional treatment and good oral health habits) it is reversible.

10 Early Signs of Gum Disease You’re Probably Ignoring

However, if you get lazy with your oral health care, brushing your teeth just once a day and canceling your dentist appointments, untreated gingivitis morphs into full-blown periodontitis. Plaque can spread to below the gum line and irritate the gums, which leads to a chronic inflammatory response in your body that essentially turns on itself, leaving your teeth and gums victims of bone and tissue loss. (Check out these 10 early gum disease warning signs.) As a result, pockets are formed between the teeth and gums and become infected. As periodontitis progresses, pockets get deeper and more gum tissue and bone loss ensue. In some cases, you may even lose your teeth.

How often to brush your teeth, then? Stick with Dr. Gause’s advice: “It can be tempting to only brush once a day, especially after a long day of work or a night out, but brushing, flossing, and rinsing should be a part of every morning and evening routine.” Now that you know how often to brush, learn the 8 brushing mistakes you have to avoid.

Reader's Digest
Originally Published in Reader's Digest