People with gum disease may be at increased risk of dementia, according to a new study.
Scientists took samples of cerebrospinal fluid — which surrounds the brain and spinal cord — and performed bacterial swabs on the gums of volunteers.
It revealed people with poor oral health also have higher amyloid beta levels, a dangerous protein found in the brain of Alzheimer's sufferers.
Gum disease is a common affliction which has a range of causes, with poor oral hygiene, stress, age and smoking all factors which increase a person's risk.
The best way to prevent and treat gum disease, according to the NHS, is a good cleaning regimen, including brushing teeth twice a day for two minutes, using a good toothpaste, flossing, and regular visits to the dentist.
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Gum disease is a common affliction which has a range of causes, with poor oral hygiene, stress, age and smoking all factors which increase a person's risk. People with the condition may be more at risk of dementia, a study claims
Beta amyloid proteins clump together in the brain and form plaques which surround nerve cells, inhibiting brain function and leading to cognitive decline.
But while a link has been firmly established between the protein and dementia, exactly how beta amyloid causes the disease remains only partially understood.
One leading theory is that proinflammatory diseases, such as gum disease, prevent the body from flushing out any amyloid from the brain.
To study the connection, American scientists took gum swabs and cerebrospinal fluid samples from 48 healthy volunteers, all aged over 65.
People in this age group are at increased risk of both dementia and gum disease, with 70 per cent of over-65s suffering from the oral condition.
Scientists took samples of cerebrospinal fluid — which surrounds the brain and spinal cord — and performed bacterial swabs on healthy volunteers. It revealed people with poor oral health also have higher amyloid beta levels, a protein found in the brain of Alzheimer's sufferers
Adults who suffer from gum disease are TWICE as likely to have high blood pressure
People with severe gum disease are twice as likely to have high blood pressure, according to a new study.
A study of 250 people with periodontitis — severe gum disease — found people with the condition are 2.3 times more likely to have a systolic blood pressure higher than 140 mm Hg, the medical threshold for hypertension.
Periodontitis is an infection of the gums that often leads to bleeding and can result in tooth or bone loss.
Researchers from University College London studied both systolic and diastolic blood pressure — how much force the blood is under when the heart contracts and relaxes, respectively.
Both metrics are measured in millimetres of mercury (mmHg) and people with gum disease have, on average, a 3.36 mm Hg higher systolic pressure.
Their diastolic blood pressure is also elevated by 2.16 mm Hg compared to people with impeccable dental health.
Bacteria balance for all 48 people was compared to levels of beta amyloid and tau, another protein known to be present in dementia patients.
Scientists determined the level of 'good' bacteria, such as Corynebacterium and Actinomyces, and compared it with the presence of 'bad' bacteria, including Prevotella and Porphyromonas.
Data shows that individuals with more good bacteria than bad bacteria in their gums had lower levels of amyloid in their cerebrospinal fluid, indicating they are less at risk of dementia.
'To our knowledge, this is the first study showing an association between the imbalanced bacterial community found under the gumline and a cerebrospinal fluid biomarker of Alzheimer's disease in cognitively normal older adults,' said Dr Angela Kamer from the New York University College of Dentistry and the study's lead author.
'The mouth is home to both harmful bacteria that promote inflammation and healthy, protective bacteria.
'We found that having evidence for brain amyloid was associated with increased harmful and decreased beneficial bacteria.'
The researchers speculate that having lots of healthy bacteria in a person's mouth may help fight off inflammation and protect against Alzheimer's.
'Our results show the importance of the overall oral microbiome - not only of the role of 'bad' bacteria, but also 'good' bacteria - in modulating amyloid levels,' said Dr Kamer.
'These findings suggest that multiple oral bacteria are involved in the expression of amyloid lesions.'
Researchers did not find evidence of tau proteins in the samples taken from the participants, even when a person had high amyloid levels.
As a result they are unable to say whether tau lesions will develop in the people with high amyloid levels, or if they will in fact go on o develop Alzheimer's.
The researchers are now setting up a clinical trial to investigate if improving gum health with deep cleans can modify brain amyloid and prevent Alzheimer's disease.
Women who read newspapers and men that use a mobile phone are LESS likely to develop the disease, study finds
Certain intellectually stimulating leisure activities reduce the risk of dementia, a study has found.
Women, but not men, who regularly read a newspaper are 35 per cent less at risk of dementia than the rest of the population.
Men however, are 36 per cent less at risk of dementia if they regularly use a mobile phone. The same protection was not seen for women.
Analysis also revealed married people who participate in a pastime or hobby are 30 per cent less at risk of dementia.
First author of the study, Pamela Almeida-Meza, a PhD student at UCL, told MailOnline: 'In the fight against dementia, it has been well established that certain modifiable risk factors such as cardiovascular health and depression management are essential for prevention.
'However, our new findings contribute to the evidence showing that in addition to this, we can provide our brains with the ability to tolerate damage while retaining function by choosing to engage in enjoyable lifestyle.
Researchers investigated the role a range of activities played on dementia risk by following more than 8,000 over-50s for up to 15 years.
They looked at 13 leisure activities and their influence — six were deemed to be 'intellectual' and included hobbies, reading the paper, using a mobile phone, and being online.
Seven were considered 'social' and included such things as being a member of a sports club, going on holiday, socialising with friends, and volunteering.
Ms Almeida-Meza said that doing more activities increased a person's protection. For each additional activity the risk of dementia dropped by nine per cent.