Cigarette smoking alters the mouth microbiota

Smoking significantly changes the mouth's microbiome, with potential implications for tooth decay and the ability to break down toxins, according to results published in the ISME (International Society for Microbial Ecology) Journal.

[girl smoking]
Smokers' mouths have lower levels of the bacteria that break down smoking-related toxins.

Cigarette smoking is the number one cause of preventable disease and mortality in the US, leading to 480,000 deaths annually, or 20% of all deaths.

Over 16 million people live with a smoking-related illness in the US, according to figures from the Centers for Disease Control and Prevention (CDC).

In 2014, the CDC estimated that 16.8% of Americans aged 18 years and over were cigarette smokers, or around 40 million adults.

Much recent research has focused on imbalances in the gut microbiota and how they relate to immune disorders such as Crohn's disease and gastrointestinal cancers.

There are around 600 species of bacteria in the human mouth. Over 75% of oral cancers are thought to be linked to smoking, but it remains unclear whether microbial differences in the mouth affect the risk for cancer.

Higher levels of Streptococcus in smokers' mouths

Researchers from New York University Langone Medical Center and its Laura and Isaac Perlmutter Cancer Center have been using precise genetic tests to investigate the impact of smoking on the composition and action of oral microbiota.

Fast facts about quitting smoking

  • In the US, there are more former smokers than current smokers, according to the CDC
  • In 2010, 68.8% of American smokers wanted to quit
  • In 2013, 48% of smokers in high school had tried to quit in the past year.

Learn more about quitting smoking

The team used mouthwash samples from 1,204 American adults who are registered in a large, ongoing study into cancer risk, funded by the National Institutes of Health (NIH) and the American Cancer Society (ACS).

Participants were all aged 50 years or over. Among them were 112 smokers and 521 individuals with no history of smoking. There were also 571 people who had quit smoking, 17% of them having stopped within the past 10 years.

Using genetic tests and statistical data, the researchers analyzed the thousands of bacteria residing in the mouths of volunteers.

Results suggest that the oral microbiome of smokers is significantly different from that of people who have never smoked or are no longer smoking. In the mouths of smokers, the levels of 150 bacterial species were significantly higher, while levels of 70 other species were distinctly lower.

Proteobacteria made up 4.6% of overall bacteria in the mouths of smokers, compared with 11.7% in nonsmokers. Proteobacteria are thought to play a part in breaking down the toxic chemicals introduced by smoking.

By contrast, 10% more species of Streptococcus were found in the mouths of smokers, compared with nonsmokers. Streptococcus is known to promote tooth decay.

Recovery comes after quitting smoking

On quitting smoking, however, the oral microbiome appears to return to its previous state. In people who had smoked previously, but not in the last 10 years, the microbial balance was the same as in the mouths of nonsmokers.

Senior investigator and epidemiologist Jiyoung Ahn, PhD, says:

"Further experiments will be needed, however, to prove that these changes weaken the body's defenses against cancer-causing chemicals in tobacco smoke, or trigger other diseases in the mouth, lungs or gut."

Co-lead investigator Brandilyn Peters, PhD, points out that the results do not reveal how long it takes former smokers' microbiome to find its balance after quitting.

The authors are planning further studies to establish the precise timeline for recovery of the bacterial community in the mouth.

They also hope to understand the biological changes that occur in the oral microbiome as a result of smoking, and how these changes might affect the risk for various cancers of the mouth and elsewhere in the body.

Medical News Today recently reported on research suggesting that the effect of some smoking cessation therapies may be limited.

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World Oral Health Day: Five things you should know about THE POWER OF A SMILE!

To mark World Oral Health Day 2016 on Sunday 20 March the British Dental Health Foundation want to make sure everybody understands the enormous power that lies behind a smile.

We want you to take a moment and think about how a simple smile can be one of the most powerful tools at our disposal… and we all have one.

So to help everyone understand the power of a smile we have put together some of our favourite facts about smiles:

  • Charles Darwin who was one of the first to really look at the power of a smile. He noted that smiling is truly universal, unlike other physical actions such as body language, or verbal communication, which differs from culture-to-culture, we all understand a smile and the feelings behind it.
  • Smiles are hugely infectious.  So even if we don't feel much happier straight away, by smiling the people around us are more likely to smile, and that can then improve our mood as well.
  • A smile can really have a big effect our relationships.  More than half of people make a smile one of the first things that people notice about others and one of the most attractive features people can have.
  • A smile can also benefit our professional life too. A smile is seen as friendly and trustworthy; interviewers are likely to find candidates far more appealing if they go for a job interview with smile on their face.
  • It really is easier to smile too. I am sure you would have heard that it takes less muscles to smile than frown, this really is true 43 to frown and only 17 to smile!

World Oral Health Day is an excellent opportunity to let you know about the power of smile and discuss how important vitally oral health can be to our confidence, happiness and health.

You may have heard recent press about the amount of children with oral health problems. New statistics revealed more than 33,000 children were admitted to hospital for tooth extractions under general anaesthetic in the last year alone.

We cannot let poor oral health stop our children from smiling!

It's important that we are all aware of the correct way to look after our oral health to make sure maintain our smiles.

Looking after our smile should be quite simple, if you make sure you follow our three key messages:

  • Brush your teeth last thing at night and on at least one other occasion with a fluoride toothpaste.
  • Cut down on how often you have sugary foods and drinks.
  • Visit your dentist regularly, as often as they recommend.

Try to share a smile, not just on World Oral Health Day but every day, and bring a bit of happiness to those around you.

World Oral Health Day is celebrated every year on 20 March. It is an international day to celebrate the benefits of a healthy mouth and to promote worldwide awareness of the issues around oral health and the importance of oral hygiene to looking after everyone old and young.

It is a day for us to have fun – this should be a day full of activities that make us laugh, sing and smile!

To find out more about World Oral Health Day visit www.worldoralhealthday.com