刮舌头比刷舌头更能去口臭，可舌头上的细菌也在帮你降血压

When you get up in the morning, you brush your teeth first.

But do you brush your tongue?

Now, lots of people do one more thing every morning: scrape their tongues.

They buy a little tool, put it at the back of the tongue, pull it forward, and the white layer on the tongue comes right off.

This white layer has a name: tongue coating.

The tongue coating has lots and lots of bacteria.

Bacteria are extremely small; your eyes can't see them, but they're alive.

Some bacteria make your mouth smell bad.

Bad breath is when your mouth has a bad smell while you talk, and other people feel uncomfortable.

So lots of people think: scrape off the coating, and your breath won't smell.

Tongue scraping actually isn't new.

In India, people started scraping their tongues long ago.

Now it's popular in many countries, and lots of young people buy tongue scrapers online.

So does tongue scraping really work?

In 2004, a study in Brazil asked 10 people to try it.

First, these 10 people brushed their tongues with a toothbrush, and the bad smell in their mouths dropped by 45%.

Then the same 10 people used a tongue scraper, and the smell dropped by 75%.

So when it comes to fighting bad breath, scraping beats brushing.

But note: this study had only 10 people — too small.

Later, experts looked at all such studies together and found only 2 small ones.

They said: tongue scraping can reduce bad breath a little, but not for long — scrape today, and you'll have to scrape again tomorrow.

At this point, the story seems to be over.

But the bacteria on your tongue have another side.

Not all the bacteria on your tongue are bad.

Some bacteria help your body.

When you eat green vegetables, like spinach, there's a kind of substance in them.

The good bacteria on your tongue can turn it into something good for your blood vessels, lowering your blood pressure a little.

Blood pressure is how much force your blood has as it flows through your body.

Blood pressure that's too high is bad for your heart.

In 2019, a study asked 26 people to use a very strong mouthwash twice a day.

Mouthwash is the liquid you rinse your mouth with; it can kill lots of bacteria in your mouth.

After 7 days, these 26 people's blood pressure rose from 113 to 115.

Not much, but it's clear: with fewer good bacteria, blood pressure went up a little.

So does tongue scraping also scrape away the good bacteria?

The same study found that people who often scrape their tongues actually had more of the helpful bacteria.

Because tongue scraping only removes the coating; it doesn't kill all the bacteria.

So the researchers say: scraping your tongue, plus eating more green vegetables, may be good for your blood pressure.

One last thing: if your bad breath is very serious and never goes away, it's best to see a doctor — don't rely only on tongue scraping.

Think about it: tomorrow morning when you brush your teeth, will you scrape your tongue too?