Brushing your teeth twice a day for at least two minutes may lower the risk of cardiovascular diseases, a new study suggests.

Previous studies have found a link between heart disease and periodontal disease – a condition marked by gum infection, gum inflammation and tooth damage.

Observational study has limits

The new study, scheduled for presentation at the American Heart Association’s Scientific Sessions meeting in Chicago, looked at whether a person’s tooth-brushing habits were associated with their risk of having or dying from a heart attack, heart failure or stroke.

Researchers asked 682 people about their tooth-brushing behaviour. After adjusting for various factors, they found that those who said they brushed less than twice a day for less than two minutes had a three-fold increased heart risk, compared to those who said they brushed at least twice a day for at least two minutes.

Dr Shogo Matsui, the study’s lead researcher, said the findings suggest “poor oral health, based on daily teeth-brushing behaviour, is associated with” poorer heart health. It’s possible that longer tooth brushing might reduce this risk, but the new study was not designed to prove cause-and-effect, said Matsui, a researcher at the Institute of Biomedical and Health Sciences at Hiroshima University in Japan.

Dr Ann Bolger, a cardiologist and professor of medicine emeritus at the University of California, San Francisco, agreed that the observational study had limitations.

“It is possible that people who are very attentive to their dental health are also very attentive to other aspects of their health,” said Bolger, who was not involved in the research.

Even so, Bolger said the science supports a potential connection between dental health and heart health. Gum disease is one of the diseases “where the body may be in a sort of continual state of inflammation, and this seems to be a very powerful predictor of cardiovascular disease,” she said.

Low-risk, low-cost option

A separate study published last month in the journal Hypertension found that gum disease appears to worsen blood pressure and interferes with medications to treat hypertension.

Poor dental health also poses a risk to people with heart valve problems, Bolger said.

“I spend an inordinate amount of time talking to (heart valve patients) about their teeth because we know certain heart valve infections can be associated with poor oral health,” she said.

This latest research “is a good reminder that the mouth is an important part of a person’s entire health and simple, daily behaviours that improve health are incredibly important.”

The American Dental Association recommends brushing your teeth twice a day for two minutes with fluoride toothpaste.

“It’s a low-risk, low-cost option that we know has other benefits even beyond the scope of what this study is trying to investigate,” Bolger said. “There’s no reason not to recommend someone do this.”

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When unborn babies kick in the womb, they may be developing awareness of their bodies, British researchers say.

“Spontaneous movement and consequent feedback from the environment during the early developmental period are known to be necessary for proper brain mapping in animals such as rats. Here we showed that this may be true in humans, too,” said study author Lorenzo Fabrizi of University College London.

His team measured the brain waves of 19 newborns during rapid eye movement (REM) sleep. The babies were an average of two days old, and some were premature. The researchers found a link between movement and brain activity.

For example, movement of a newborn’s right hand causes immediate activity in the left part of the brain that processes touch for the right hand. The size of these “fast brain waves” is largest in premature babies, who would normally still be in the womb, the researchers said.

Sensory input

The fast brain waves associated with movement end by the time a baby is a few weeks old, the researchers added.

These findings suggest that foetal movement in the third trimester of pregnancy helps to develop areas of the brain that process sensory input. This is how a baby develops a sense of its own body, according to the study authors.

The research could improve care for premature infants, Fabrizi and his colleagues said in a university news release.

Safe environment

“We think the findings have implications for providing the optimal hospital environment for infants born early, so that they receive appropriate sensory input,” said study co-author Kimberley Whitehead. She’s in the university’s department of neuroscience, physiology and pharmacology.

For example, it’s already routine for infants to be “nested” in their bassinets. This allows them to “feel” a surface when they kick their limbs, as if they were still inside the womb, Whitehead noted.

“As the movements we observed occur during sleep, our results support other studies which indicate that sleep should be protected in newborns, for example by minimising the disturbance associated with necessary medical procedures,” Whitehead said.

The findings were published in the journal Scientific Reports.

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With the national shortage of primary care doctors and – in certain areas – specialists, and with a quarter of the population living in rural areas without easy access to care, telehealth has stepped in to help fill the gap.

In fact, millions of Americans now use it every year.

Telehealth involves virtual office visits. Note that you’ll also see the term telemedicine, which usually refers to virtual visits with a doctor. Telehealth is broader and includes care from other types of health professionals, such as nurses.

During “visits” you video chat with a health-care professional through your smartphone, tablet or computer, sometimes with no waiting time. And it all happens in real time.

Virtual visits

Telehealth services vary from getting a diagnosis and a prescription, if needed, for minor medical issues, to ongoing monitoring of chronic conditions – especially helpful to older Americans. As an example, your heart rate or blood sugar levels can be sent remotely to your doctor’s office and he or she can review them with you while you have your virtual visit.

One study found that the most common virtual visits were for acute respiratory problems, urinary tract infections and skin complaints. In fact, telehealth can be very helpful in dermatology, a specialty that’s short on doctors.

Telehealth for mental health care is another growing area. Video sessions can help people stick with their treatment plan if getting to a therapist’s office is difficult. And it can be just as effective as face-to-face appointments.

Some health insurance providers now offer telehealth as an option in some of their plans. There’s usually a fee for a telehealth visit, but it can be lower than your in-office co-pay. If you’re on a high-deductible plan, the cost will certainly be less than you’d pay out-of-pocket for an office visit.

The Veterans Administration is just one of many government agencies that offers a variety of telehealth services.

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Contrary to common belief, blood pressure doesn’t have to rise as you age, a study of two remote South American tribes suggests.

Looking at the isolated Yanomami tribe in the Venezuelan rain forest, researchers found their blood pressure remained low from youth to age 60.

Access to Western-style foods

That’s probably because as hunter-gatherer-gardeners, they don’t eat the processed and salted foods common in the so-called Western diet, the researchers said in a new report.

“The association between age and blood pressure may not be driven by age itself, but rather the cumulative effects of a Western lifestyle and dietary practices,” said lead researcher Noel Mueller, an assistant professor of epidemiology at Johns Hopkins University School of Public Health.

Another local tribe, the Yekwana, had some access to Western-style foods, and their blood pressure started increasing in childhood, said Mueller.

“We believe that rising blood pressure is due to the consumption of processed foods and salt,” he said. This is what the report refers to as “unnatural Western exposures”.

About one in three American adults has high blood pressure, according to the US National Institutes of Health. Left untreated, high blood pressure, or hypertension, can lead to heart attack, stroke, sexual dysfunction and other health problems.

Dr Harlan Krumholz, a professor of cardiology at Yale University, was enthusiastic about the new findings.

“This small study introduces a remarkably powerful idea – that an increase in blood pressure with age is not inevitable,” said Krumholz, who wasn’t involved with the study.

No salt or added sugar

It is entirely plausible that a healthy lifestyle could protect against the growing risk of hardening of the arteries with increasing age that is so prevalent in Westernized societies, he said.

Over five months, Mueller and his team measured the blood pressure of 72 Yanomami and 83 Yekwana members who were between one and 60 years old.

The Yekwana are less isolated than the Yanomami. Because of missions and an airstrip, the Yekwana have some contact with the outside world, including Western-style eating, the researchers noted.

The study found no age-related increase in blood pressure among the children and adults of the Yanomami. But among the Yekwana, blood pressure began increasing in childhood and went up about 0.25 mm Hg a year on average, Mueller said.

The Yanomami diet consists of fruits, vegetables and meats from the animals they hunt. Fibre and carbohydrates make up the bulk of their diet, however. “No salt and no added sugar,” Mueller said.

Keeping blood pressure low is key to preventing cardiovascular disease, Mueller said, adding that age-related blood pressure spikes shouldn’t be taken for granted.

“We can prevent it with interventions that reduce the intake of salt in our diet,” he said.

No direct cause-and-effect relationship

Life deep in the isolated rainforest isn’t all rosy, however. Mueller acknowledged that the Yanomami life span is shorter than that in developed countries because they lack access to antibiotics and other medicines that could prevent or cure infections and diseases.

Warring with other tribes also shortens their lives, Mueller said.

The study can’t prove a direct cause-and-effect relationship. Still, “it is worth studying whether the effect of age on our vascular system can be slowed, stopped or even reversed with a healthy lifestyle – and what particular elements of a healthy lifestyle might make the most difference,” Krumholz said.

As to whether salt is to blame for blood pressure rising with age, Krumholz isn’t sure.

“There are so many ways that modern society is different from the era in which cardiac disease was rare,” Krumholz said.

Differences in dietary, behavioural and environmental exposures make it hard to pinpoint the exact cause of these blood pressure discrepancies, he said. “It is likely, in the end, to be a result of the combination of factors,” Krumholz noted.

The report was published online in JAMA Cardiology.

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Do so-called hypoallergenic dogs really protect you against asthma?

Many dog-lovers believe it, but Swedish researchers found no evidence that “allergy-friendly” breeds – such as poodles and miniature Schnauzers – actually lower the risk for the wheezing lung disease.

No evidence for ‘hypoallergenic’ dogs

Previous studies have shown that growing up with dogs can reduce a child’s asthma risk, but researchers wondered if the type of dog makes a difference. For this study, they wanted to see if variables such as sex, breed, size or number of dogs affected the risk of asthma and allergy during a child’s first year of life.

Researcher Tove Fall of Uppsala University in Sweden led the study. She’s a senior lecturer in the department of medical sciences.

“The sex of the dog can affect the amount of allergens released, and we know that uncastrated male dogs express more of a particular allergen than castrated dogs and female dogs,” Fall said. “Moreover, some breeds are described anecdotally as ‘hypoallergenic’ or ‘allergy friendly’ and are said to be more suitable for people with allergies, but there is no scientific evidence for this.”

For the study, the researchers collected data on 23 600 children, born in Sweden between 2001 and 2004, who had a dog in their home for the first year of life. The investigators linked that information with two dog owner registries that classified dogs by sex, breed, number, size and claimed “hypoallergenicity”.

The researchers then compared the dogs’ characteristics to the risk of asthma and allergies or the prescription of asthma or allergy drugs for children at age six. They took into account known factors that could affect risk, including parental asthma and allergy, geographical location and number of siblings.

No increased risk for asthma

The analysis revealed that 5.4% of six-year-olds had asthma. And children who had female dogs had a 16% lower risk than those with male dogs.

But living with a male dog did not put kids at higher risk than having no dog at all, the findings showed. And children in families with two or more dogs had a 21% lower risk of asthma than those with just one.

Kids whose parents themselves have asthma or allergies more often had dogs described as “hypoallergenic” than did other children (12% versus 8%), according to the report.

Exposure to these breeds was tied to a 27% higher risk of allergy, but no increased risk for asthma.

Study co-author Catarina Almqvist Malmros is a professor in the department of medical epidemiology and biostatistics at the Karolinska Institute in Stockholm.

Malmros cautioned that the study findings can’t prove that certain breeds cause asthma or allergies, only that there is an association.

“The likely explanation for this higher risk is that families with a history of allergy to furred pets more often choose these dogs, and also that ‘allergy-friendly’ dogs do not in fact release less allergens,” she said in a university news release.

The report was published online in the journal Scientific Reports.

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Is it just down to evolution or male sperm swimming that little bit faster?

Sleep disruption has a big effect in the short-term – but what about longer term?

Strangers with long-term mental and physical illnesses are being paired up and encouraged to send gifts to one another to stop them feeling isolated.

Stress in the evening may take more of a toll on your body than stress at other times of day, a new study suggests.

The reason? Later in the day, the human body releases lower levels of the hormone that helps ease stress, according to researchers from Japan.

Acute stress response

“Our study suggests a possible vulnerability to stress in the evening,” said study leader Yujiro Yamanaka, a medical physiologist at Hokkaido University in Sapporo.

“However, it is important to take into account each individual’s unique biological clock and the time of day when assessing the response to stressors and preventing them,” Yamanaka said in a university news release.

The researchers measured levels of the stress hormone cortisol in the saliva of 27 young, healthy volunteers.

They also exposed them to a stressful situation to see if the hypothalamic-pituitary-adrenal (HPA) axis responds differently to acute stress at different times of day.

The HPA axis connects the body’s central nervous and endocrine systems. When a stressful event activates the axis, the body releases cortisol.

Cortisol levels are also controlled by the circadian clock in the brain.

Saliva samples

The volunteers were divided into two groups. One group was exposed to a stress test in the morning, two hours after waking up. The other group was exposed to a stress test in the evening, after being awake for 10 hours.

The 15-minute test involved preparing and giving a presentation to three interviewers and a camera. Participants also had to do mental arithmetic.

The researchers took saliva samples half an hour before the test, immediately after, and at 10-minute intervals for another half hour.

Cortisol levels increased significantly in the morning, but not in the evening, the results showed. However, participants’ heart rates – an indicator of the sympathetic nervous system’s response to stress – did not differ.

“The body can respond to the morning stress event by activating the HPA axis and sympathetic nervous system, but it needs to respond to evening stress event by activating the sympathetic nervous system only,” Yamanaka said.

The report was published recently in the journal Neuropsychopharmacology Reports.

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The number of staff suspended at Muckamore Abbey Hospital has risen to more than 20, the BBC understands.