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Failure to brush your teeth twice a day increases risk of heart disease

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brush teeth twice daily heart cardiovascular disease riskNever mind your dentist. Your cardiologist might want you to brush your teeth more often.

Neglecting to brush twice a day could lead to a 70 percent increased risk of cardiovascular disease, according to a new large population-based study.

Researchers examined self-reported oral hygiene habits and coronary disease in 11,869 adults aged 35 and older (with a mean age of 50) from the Scottish Health Survey—a study conducted once every three to five years—between the years 1995 and 2003. The team, led by Cesar de Oliveira, a research fellow in epidemiology and public health at University College London, followed up with subjects after an average of eight years to see if they had had a heart attack or coronary disease.

Even though the researchers found that those who reported brushing their teeth less than twice a day were more likely to be male, older, smokers and to have other health issues (such as diabetes, hypertension and obesity), the team controlled for those variables and others and still found that tooth brushing is associated with cardiovascular disease. The association held even after adjusting for socioeconomic group, visits to dentist, BMI, family history of cardiovascular disease, hypertension and diagnosis of diabetes.

The findings were published online May 27 in the British Medical Journal.

Many previous studies have found a similar link, although other data have shown more modest increases in risk. One study from 2000, however, failed to find a convincing link between periodontitis and chronic coronary disease in a study of more than 8,000 people followed for 20 years. But the authors of the new paper noted that having periodontal disease increases the risk of getting cardiovascular disease in the future by 19 percent (that figure jumps to 44 percent for people who have periodontal disease before they are 65). That level of risk increase could "have a profound public health impact," the authors noted.

Although the study isn’t proof of causation, the researchers highlight inflammation as a possible mechanism behind the link between periodontal disease and heart disease.

Chronic inflammation—and the body’s response to it—is thought to be a factor for heart disease, and as the authors noted, periodontal disease "is one of the most common chronic infections and is associated with a moderate systemic inflammatory response."

As part of the study, de Oliveira and colleagues also tested blood samples from 4,830 of the survey subjects for two key inflammatory markers (C reactive protein and fibrinogen). They found a strong association between poor oral hygiene routines and high levels of these markers, suggesting inflammation as a possible link between oral and heart health. The possibility should be enough, the authors noted, to suggest that, "doctors should be alert to the possible oral source of an increase inflammatory burden." And it might just be another reason for people to brush more often.

Image courtesy of iStockphoto/diego_cervo

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  1. 1. promytius 9:14 pm 05/27/2010

    Sloppy research, sloppy reporting; there is NO releationship between brushing teeth and heart attacks, period – totally absurd! There MAY be a relationship between brushing gums to prevent infammatory deseases and heart attacks, but you have to report it that way. Thanks at least for not using "actually" anywhere in the article.

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  2. 2. jtdwyer 10:24 pm 05/27/2010

    promytius, redredred – Modern medical myths wouldn’t surprise me, but my dentist offers pretreatment with antibiotics. Meanwhile, my cardiologist claims my congestive heart failure is most likely the product of respiratory infections, but he doesn’t explain much. Is antibiotic pretreatment an unnecessary procedure?

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  3. 3. hawkeye 12:33 am 05/28/2010

    jtdwyer – the simple answer to your question is "nobody knows". As the others have alluded, the article notes a correlation between oral hygiene (read "periodontal disease") and cardiovascular disease, then leaps to the conclusion that brushing teeth somehow protects against cardiovascular disease.

    The term "cardiovascular disease" itself is a very imprecise term; while it does include "heart attacks" (myocardial infarction, resulting from vascular occlusion of cardiac blood vessels), that is only one of multiple diseases affecting the heart, which are totally unrelated to one another.

    Of what little we do know about the one form of cardiovascular disease that causes heart attack (ASHD), we know that frequently there are associated indications of inflammatory reactions taking place in the body (C-reactive protein, etc), but we have a long way to go before we understand what that means.

    You mention congestive heart failure. While that condition can be a result of ASHD ("heart attacks"), there are multiple other causes as well. Your cardiologist mentions respiratory infections; that would seem to indicate that he thinks the cause of your congestive heart failure (CHF) is a condition known as cardiomyopathy. It occurs when a viral infection settles in the heart and causes direct damage to the heart muscle. It has nothing to do with the blood vessels of the heart, and is not caused by blood vessel disease.

    When anyone has dental work done, it has been demonstrated that a shower of bacteria from the gums, into the blood stream, takes place. Most of the time, the body’s defenses against bacterial invaders can easily remove them, with no resulting problems.

    However, in some cases , especially those involving abnormalities of the heart valves or cardiac function, those bacteria can settle in the heart, causing a life threatening condition called "bacterial endocarditis".

    I don’t know the details of your case, but the use of prophylactic antibiotics for dental procedures has been around a long time, and is recommended for conditions such as those described above.

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  4. 4. takhisis 12:52 am 05/28/2010

    How can you say "the study isn’t proof of causation", and have "Failure to brush your teeth twice a day increases risk of heart disease" as the title? This is very misleading reporting.

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  5. 5. Iahmad 2:44 am 05/28/2010

    Is it possible that people who brush their teeth regularly are more health consious (having healthy diet and regular exercise) which may contribute to better cardiovascular outcome rather than brushing itself. Nonetheless it is a good hygenic practice.
    Islamic traditions strongly recommned brushing teeth during ablutions for five daily canonical prayers.

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  6. 6. alanrlow 5:03 am 05/28/2010

    What a bogus report. While waiting for the clock to run down on the ridiculous lipid hypothesis that saturated fat causes heart disease now we have this preposterous rubbish.

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  7. 7. dweed 10:03 am 05/28/2010

    I did my own study and concluded that the people who thought this study bogus do not brush their teeth.

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  8. 8. samiup 10:05 am 05/28/2010

    interesting, but sounds pretty premature to make any conclusions, maybe older people say the truth about their brushing habit?

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  9. 9. OutwardBound247 11:07 am 05/28/2010

    Immediately following a fusion at L5-S1, I developed an infection in my spine that required a ten day I/V regimen of antibiotics and morphine. It was later discovered that I had an infection under a molar resulting from a botched root canal. They were certain that infection had caused the post operative infection.
    So, "Yes", I believe tooth decay could easily infect ones heart with disease over time.
    Oh yeah…don’t forget to floss!

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  10. 10. Chuck Arthur 11:32 am 05/28/2010

    Periodontal disease is directly influenced by vitamin D deficiency. The silent killer also seems to reflect the status of vascular health as well.

    Maintaining a serum level of at least 50 ng/ml, 25 OH D (activated vitamin D), year round, will greatly improve gum health.

    Generally speaking if your gums are in bad shape, so are your arteries and heart.

    Brushing your teeth does not address the root cause of the issue: Low vitamin D levels on a chronic basis.

    Multiple studies have shown irrefutable evidence that tooth loss is reduced significantly when vitamin D levels are at healthy, natural norms. Investigate this fact and see for yourself the proven link between oral pathology and chronic vitamin D deficiency.

    In a large study conducted amongst Mormon patients 2 years ago it was observed that heart disease was developed when serum 25 OH D (activated vitamin D) levels fell below 34 ng/ml.

    Vitamin D, when metabolized, becomes the human bodys most powerful steroid hormone, approximately 1 trillion times as potent as testosterone, by molecular weight.

    Educate your doctors about vitamin D and in the process almost certainly save yourself from early onset, chronic diseases.

    Chronic vitamin D deficiency is by far the worlds greatest health crisis. It does not matter if you have not heard this proclamation before. New vitamin D deficiency research has moved far ahead of almost anyones recognition.

    You cannot be healthy unless your vitamin D serum level is at least 50 ng/ml, 25 OH D, year round.

    To reiterate, educate your doctors and health care professionals. Pass along what you have learned and save those you love a literal lifetime of unnecessary suffering and avoid early death.

    Vitamin D information sites:

    Vitamin D Council:

    Grassroots Health:

    Vitamin D3 World:

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  11. 11. Chuck Arthur 11:37 am 05/28/2010

    Actually the research of the last 2 years points directly at chronic vitmain D deficiency. This in terms of vascular and oral health.

    Vitmain D is by far the body’s most powerful anti inflammatory steroid hormone, apprx, 1 trillion times more potent than the somwehat similar molecules such as testosterone and estrogen.

    The link between oral health, tooth loss, vascular disease and chronic vitamin D deficiency can’t be denied.

    See comment submitted @ 11:30

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  12. 12. billsmith 12:29 pm 05/28/2010

    News reports make causation claims in the headline ALL THE TIME when the scientists being quoted did no such thing. The fact that this article does not gloss over the messiness of science in the usual way speaks well of the author’s source.

    Gum disease (periodontitis) and dental surgery have been shown to cause bacteria to circulate in the blood (bacteremia). Bacteremia in turn has been shown to increase the risk of damaging inflammation to the heart. So while you may have some questions, this is not "preposterous rubbish" but a well-established, legitimate area of research.

    Try a search of "periodontal disease cardiovascular disease" on for a list of scientific journal articles from a wide variety of sources. You will find that most of the scientists, unlike most headline writers, will make nuanced and cautious conclusions and say just what they can support- no more and no less.

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  13. 13. jtdwyer 1:34 pm 05/28/2010

    hawkeye – Good diagnosis! Yeah, cardiomyopathy and significant mumur… Thanks!

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  14. 14. Pranay Dogra 3:00 pm 05/28/2010

    Well I guess in a gum infections lead to a generalised inflammatory response of the body. The higher levels of CRP and fibrinogen do suggest an direct inflammatory response, however I would appreciate if the authors would also report the occurance of other inflammatory disorders like Rheumatoid arthritis and spondylitis in the subjects of their study. Inflammation is a complex process and a lot needs to be learnt about it, which may then answer many questions. Till that time it is best to brush our teeth, to be on the safer side.

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  15. 15. hawkeye 12:01 am 05/29/2010

    jtdwyer – You’re welcome. That being the case, I would by all means recommend that you take advantage of antibiotics prior to having dental work done. As a physician, I can attest that it ain’t no fad; it’s the real deal.

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  16. 16. Forlornehope 4:38 am 05/29/2010

    Knowing my countrymen as I do (I’m a Scot), I find it very difficult to understand how you could find a significant sample who do not have good dental hygiene yet control for all the other life-style variables. The Scotsman or Scotswoman who does not smoke, drink to excess, is not overweight and does not have some kind of chronic ill health, is sadly one of a minority who takes reasonable to good care of their health. Finding a significant sample in this group who do not take care of their teeth would be quite difficult and those individuals being exceptional would hardly constitute a control. It is worth pointing out for readers who may not be familiar with the local issues that, when controlling for all known factors, the rate of heart disease in Scotland is unusually high. This has been the subject of research for several decades .

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  17. 17. Ruler4You 7:04 am 05/29/2010

    While I follow the correlation and understand it, a "risk" increase isn’t a death sentence. You have to understand what he original "risk" "IS" first. But as with all correlations and especially in medicine, a notoriously dynamic science, conclusive causation based evidence can be elusive. One thing is for sure; none of us, no, not 1, are going to live forever or get off of this ball of mud alive. We are, each one of us, 1 breath or 1 heart beat from being worm food. Get used to it.

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  18. 18. jtdwyer 10:06 am 05/29/2010

    hawkeye – As a highly reluctant patient who would no longer be be able to survive without the continuous support of modern medicine, I strongly recommend that others avoid heart damage through oral hygiene and prompt treatment of low grade infections, etc. Those small efforts can prevent significant reductions in physical abilities.

    Ruler4You – Having been a strong and very active workaholic until about 10 years ago, when I suddenly began suffering serious acute symptoms of heart failure, I’m now sufficiently stabilized to the point where I can sustain, managed, low grade physical activity, like a trip to the store, for about an hour a day.

    If I could only have realized the consequences of avoiding those minor trips to the doctor treat treating a little sinus infection, or to the dentist for dental treatment, I’d have gladly exchanged those minor inconveniences for the many physical capabilities I no longer have.

    I’m very happy to have the abilities that I still have, but I’d recommend taking possible risks of serious consequences seriously, especially when mitigating those risks requires so little effort.

    I hope you don’t become a near invalid for the last 20 years of your life because you didn’t brush you teeth quite often enough! Of course, it probably won’t happen to you and even if it did, you could just get used to it, like I did.

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  19. 19. dcodrea 1:02 pm 05/29/2010

    Could just be that people who don’t invest the simple effort to brush regularly don’t invest the simple effort in other health and hygiene-related matters…

    Being a lazy slob is unhealthy. Who knew?

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  20. 20. jtdwyer 1:29 pm 05/29/2010

    dcodrea – Or could be that those who work 60 hour weeks to support their children don’t spend enough time addressing seemingly minor health problems, unaware of the potential ramifications. What do you know?

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  21. 21. sunnystrobe 1:38 pm 06/3/2010

    dwyeer: Having had bleeding gums twenty-five years ago, I have since switched to a much more vitamin-rich fruit&vegetable-based diet, which automatically cured not only my periodontal problems, but also my hypothyriodism. At age 67, my blood pressure and cholesterol and general fitness level is ideal, too.I ascribe this to the fact that a human -species-specific diet which avoids the pitfalls of vitamin deficiencies, especially vitamin C and folic acid, is the no.1 desideratum . Why do medicos tend to tend to the symptoms rather than the underlying causes of inflammation? Feeding a patient potent medications like antibiotics, which are wreaking havoc with the intestinal gut flora and its immune defence function is a recipe for disaster : vide the MSR scandal caused by veterinarians feeding chickens and cows "precautionary" antibiotics. Let’s follow the advice of Dr. Hippocrates and let FOOD be our medicine.

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  22. 22. some econ geek 6:25 pm 06/4/2010

    How is this news? Endocarditis and dental related septicemia is prevented by good dental hygiene. Dur…

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  23. 23. JerryTT 7:07 am 06/6/2014

    A bad oral health can influence your overall health. Many researches have proved that a good oral hygiene keeps you away from heart disease. Everyone must floss and brush teeth twice in a day to avoid plaque building.

    Food also plays an important role in maintaining proper care of oral health Consumption of dairy foods like, milk, cheese, yoghurt etc. contain calcium that strengthens tooth enamel and control gum recession.

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