Vệ sinh lưỡi: có nên cạo lưỡi và làm thế nào cho đúng?

Look in the mirror first thing in the morning and you may see a whitish film on your tongue, thickest near the back. Is tongue cleaning worth doing, should you scrape your tongue every day, and is a tongue scraper better than a toothbrush? This guide pulls together the studies we checked, a gentle technique, and the tongue changes you should not try to handle at home.

Why does a white coating build up on the tongue?

The top of your tongue is not smooth like the inside of your cheek; it is covered in tiny projections. The gaps between them trap shed cells, food debris, bacteria and mucus. Over time this forms a tongue coating, usually thickest at the back of the tongue, where a toothbrush rarely reaches.

The coating tends to get heavier when your mouth is dry, after a night's sleep, or if you smoke. If dry mouth is a regular problem, see dry mouth: causes and how to improve it; the effects of tobacco are covered in how smoking affects your teeth. The UK's NHS says a white tongue is usually not serious and suggests brushing your tongue or using a tongue scraper (NHS).

What does tongue scraping do? The evidence is thin

How the tongue relates to bad breath, including the 2006 Cochrane review on tongue scraping, is summarised in our article on causes of bad breath. Here are additional studies:

• Van der Sleen et al. (2010): a review of 5 studies (3 randomised and 2 controlled trials) with 7 experiments. All 7 showed that brushing or scraping the tongue on top of toothbrushing improved breath-odour measures and tongue coating. However, data on chronic halitosis were insufficient. PubMed
• Cochrane review by Kumbargere Nagraj et al. (2019): replaced the older review and pooled 44 trials with 1,809 people across all halitosis treatments. The comparison of tongue cleaning versus none rested on just 2 trials and 46 people, with very low certainty. PubMed
• Quirynen et al. (2004): 16 healthy people scraped or brushed their tongue twice a day for 2 weeks. Tongue coating fell clearly and taste became sharper (most noticeably for bitter and salty with the scraper), yet bacterial counts on the tongue barely changed. PubMed

The American Dental Association (ADA) is more direct: there is no evidence that brushing or scraping the tongue prevents bad breath, because odour-causing bacteria return almost as soon as they are removed; tongue cleaning is a personal choice, not a required step (MouthHealthy – ADA).

In short: tongue cleaning keeps the surface of the tongue clean and may make your mouth feel fresher, but it does not replace brushing your teeth and cleaning between them.

Tongue scraper or toothbrush?

• Pedrazzi et al. (2004): a crossover trial in 10 people. After one week, the scraper cut odour-causing sulphur compounds by 75% and a soft toothbrush by 45%; both removed the coating. PubMed
• Casemiro et al. (2008): in 30 people, a toothbrush with a tongue scraper on the back of its head and a separate scraper performed similarly for breath and tongue bacteria. PubMed

Both studies are very small, so the differences are only suggestive. Cleveland Clinic notes that scrapers are usually made of plastic, copper or stainless steel (Cleveland Clinic). Choose one with a smooth, rounded edge that fits your tongue. If you use a toothbrush, pick soft bristles and brush lightly.

How to do tongue cleaning with a scraper: 4 steps

Do this after brushing and cleaning between your teeth:

1. Hold the scraper and rest its edge gently on the back of your tongue, where the coating is thickest.
2. Stick your tongue out and draw the scraper forward towards the tip with light pressure.
3. Rinse the scraper under running water after each stroke.
4. Repeat a few times across the middle and sides of the tongue, then rinse your mouth with water.

A few practical tips:

• Vinmec, a Vietnamese hospital group, suggests scraping once or twice a day with about 2–5 strokes each time, replacing the scraper roughly every 3 months and storing it dry (Vinmec, Vietnam).
• Scraping should never hurt. According to Cleveland Clinic, pain means you are pressing too hard.
• If you gag easily, start a little further forward and breathe steadily through your nose.
• If your tongue feels scratched or sore, stop for a few days, avoid spicy food, then try again more gently.

When does a tongue change need a check-up?

Do not scrape hard at a patch that will not come off. According to the NHS, these signs should be seen by a doctor or dentist:

• Raised white patches that do not rub off (possibly leukoplakia).
• White patches on the tongue and inside the cheeks (possibly lichen planus).
• A red, itchy mouth with white patches on the tongue (possibly oral thrush).
• Tongue pain or itching that does not go away or gets worse.

The NHS mouth cancer page advises getting checked for a mouth ulcer lasting more than 3 weeks, red or white patches in the mouth, a lump in the mouth or on the lip, or difficulty swallowing (NHS). Cleveland Clinic also recommends seeing a dentist if your tongue turns white, black or red, or if sores last longer than 2 weeks. Most of these signs have harmless causes, but an examination is the only way to be sure.

Inmax electric toothbrushes for the brushing step

Inmax does not sell tongue scrapers, and the electric toothbrushes below have no tongue-cleaning mode. They cover the essential step: brushing your teeth twice a day.

• M5 electric toothbrush: 199.4 mm body, the shortest in the Inmax range, 20,000 vibrations per minute, 4 modes: Clean, Sensitive, Whitening, Gum Care.
• M2 Pro electric toothbrush: 135 g cylindrical body, 150–250 Hz, 5 modes: Clean, Soft, Power, Whitening, Polish.

Both run on a 1,200 mAh battery, charge via USB Type-C and are rated IPX7 waterproof. Other models are in the electric toothbrush range; you can line them up on the comparison page, ask questions via contact Inmax, and resellers can read the dealer policy.

Frequently asked questions

Should I scrape my tongue before or after brushing?

After. Both Vinmec and Cleveland Clinic place tongue scraping after brushing, followed by a rinse to wash away what you have removed.

Can tongue scraping damage my sense of taste?

Not if you are gentle. The Quirynen study actually found taste was sharper after 2 weeks. Pressing hard is what causes scratches and bleeding.

I scrape every day and my tongue is still white. What now?

See a professional rather than scraping harder. A persistently white tongue can be caused by oral thrush, lichen planus or leukoplakia, which need a diagnosis.

Do I need to buy a separate tongue scraper?

No. A soft toothbrush also removes the coating; a scraper is simply an option if you find it easier or more comfortable.

Use this information to look after your tongue sensibly at home; any unusual change on your tongue still needs to be examined in person by a doctor or dentist.