Tongue scraping involves using a tool to remove a white or yellowish coating that sometimes forms on the tongue. This is the result of buildup from food debris, dead skin cells and bacteria, said Dr. Martinna Bertolini, an assistant professor of dental medicine at the University of Pittsburgh School of Dental Medicine.

“The tongue is the only tissue in the entire body that has papillae,” Bertolini said, referring to the tiny bumps that help your tongue grip food as you eat. These papillae create pockets where buildup can accumulate.

Tongue scrapers are designed to scrape off that discolored, often smelly coating. They’re typically made of stainless steel, silicone or plastic. They involve gripping one end of the tool while you press the other end down your tongue as you scrape.

How does tongue scraping help?

Buildup on the tongue smells bad because bacterial colonies can live there, said Ananda Dasanayake, a professor of epidemiology at the New York University College of Dentistry. Some of these bacteria produce gases that are “really very stinky,” he said, adding that “that’s one reason people get halitosis,” or persistent bad breath.

Halitosis is the main reason a dentist might recommend tongue scraping, said Isabelle Laleman, a periodontist at CHU de Liège, a university hospital in Belgium. Treatments for bad breath are limited, she said. People can use a mouthwash, such as Listerine, but it will only mask the smell. Physically scraping off the source of that odor is “the best thing we have” for bad breath, Laleman said.

Few studies have been done on the effectiveness of tongue scraping for reducing bad breath and bacterial counts, and results have been mixed. One review from 2010 found that tongue scraping and tongue brushing could improve breath odor.

Other studies, including one that Laleman co-wrote and published in 2017, found that among 18 patients with periodontitis — a serious form of gum disease — tongue scraping made no difference in the amount of bacteria or odor in their mouths.

If your breath improves with tongue scraping, Bertolini said it’s important to note that those benefits will be temporary. “If you don’t do this daily, it comes back,” she said.

Should you try it?

Bertolini said she would recommend tongue scraping only to patients with halitosis, because they’re the only ones who really need it. If you have gum disease, it is a good idea to keep the amount of bacteria in your mouth as low as possible, so tongue scraping could be useful, she added. But if you are healthy and do not have halitosis, you won’t be worse off by not tongue scraping.

Nevertheless, Bertolini and Dasanayake scrape their tongues after brushing their teeth.

There are no risks associated with tongue scraping. The only potential downside: scraping too roughly and hurting your tongue, Bertolini said.

What’s the proper technique?

Using a tongue scraper is pretty intuitive, Dasanayake said. It’s a simple raking motion, requiring three or four sweeps to cover the entire tongue. He prefers scrapers with serrated edges that allow you to get into the grooves of your tongue.

If you don’t want to buy a tongue scraper, you could use a spoon, Laleman said. It’s shaped similarly, but it might be harder to reach the back areas of the tongue.