Posts tagged health
Articles and news from the latest research reports.
Your gut’s what you eat, too
As the saying goes, you are what you eat. But new evidence suggests that the same may also be true for the microbes in your gut.
A Harvard study shows that, in as little as a day, diet can alter the population of microbes in the gut — particularly those that tolerate bile — as well as the types of genes expressed by gut bacteria.
“What we are really excited about is we and others have shown in animal models that diet can rapidly have major effects on the microbes that are in the gut,” said Peter Turnbaugh, a Bauer Fellow at the Center for Systems Biology in the Faculty of Arts and Sciences. He is senior author of the paper, which appeared in Dec. 11 edition of the journal Nature.
“But it still wasn’t clear how fast the microbes in the human gut respond to changes in diet, and to what degree those changes would be similar in different people. This study is really the first time we’ve seen that, over the course of days, a new diet can reshape the microbial community, and that those changes are consistent and reversible.”
Obesity ballooning in developing world: report
The number of obese and overweight people in the developing world nearly quadrupled to almost a billion between 1980 and 2008, a think-tank report said on Friday.
There are now far more obese or overweight adults in the developing world than in richer countries, the Overseas Development Institute (ODI) said.
The London-based institute said more than a third of all adults around the world — 1.46 billion people — were obese or overweight.
Between 1980 and 2008, the numbers of people affected in the developing world rose from 250 million to 904 million. In the developed world, the figure rose from 321 million to 557 million.
This represented a rise from 23 percent to 34 percent of the world population.
"The growing rates of overweight and obesity in developing countries are alarming," said ODI research fellow Steve Wiggins, who co-authored the Future Diets report.
"On current trends, globally, we will see a huge increase in the number of people suffering certain types of cancer, diabetes, strokes and heart attacks, putting an enormous burden on public healthcare systems."
The report said overweight and obesity rates have almost doubled in China and Mexico since 1980, and risen by a third in South Africa.
The study said the rise in obesity was down to diets changing in developing countries where incomes were rising, with people shifting away from cereals and tubers to eating more meat, fats and sugar.
The over-consumption of food, coupled with increasingly sedentary lives, was also to blame.
The report found that North Africa, the Middle East and South America saw overweight and obesity rates increase to a level similar to Europe, around 58 percent.
At 70 percent, North America still has the highest percentage of overweight adults.
The report said there seemed to be little will among the public and leaders to take action on influencing diet in the future.
"Governments have focused on public awareness campaigns, but evidence shows this is not enough," said Wiggins.
"The lack of action stands in stark contrast to the concerted public actions taken to limit smoking in developed countries.
"Politicians need to be less shy about trying to influence what food ends up on our plates. The challenge is to make healthy diets viable whilst reducing the appeal of foods which carry a less certain nutritional value."
The report gave the example of South Korea as having made efforts to preserve healthy elements of the country’s traditional diet, via public campaigns and education, providing large-scale training for women in preparing healthy, traditional food.
The report said it was “only a matter of time” before people would begin to accept and even demand stronger and more effective measures to influence diets.
Celebrities and health: The good, the bad, and the ugly
Celebrities frequently give medical advice and people often follow it. Whether motivated by good intentions or financial rewards, celebrities can generate much publicity for health campaigns by virtue of their visibility, public interest, and perceived newsworthiness.
Steven Hoffman an assistant professor, and Charlie Tan a medical student, both at McMaster University, have attempted to find out why we seem so keen to follow their lead
Read the full research
Following celebrities’ medical advice: meta-narrative analysis
Yoga accessible for the blind with new Microsoft Kinect-based program
In a typical yoga class, students watch an instructor to learn how to properly hold a position. But for people who are blind or can’t see well, it can be frustrating to participate in these types of exercises.
Now, a team of University of Washington computer scientists has created a software program that watches a user’s movements and gives spoken feedback on what to change to accurately complete a yoga pose.
“My hope for this technology is for people who are blind or low-vision to be able to try it out, and help give a basic understanding of yoga in a more comfortable setting,” said project lead Kyle Rector, a UW doctoral student in computer science and engineering.
The program, called Eyes-Free Yoga, uses Microsoft Kinect software to track body movements and offer auditory feedback in real time for six yoga poses, including Warrior I and II, Tree and Chair poses. Rector and her collaborators published their methodology in the conference proceedings of the Association for Computing Machinery’s SIGACCESS International Conference on Computers and Accessibility in Bellevue, Wash., Oct. 21-23.
Rector wrote programming code that instructs the Kinect to read a user’s body angles, then gives verbal feedback on how to adjust his or her arms, legs, neck or back to complete the pose. For example, the program might say: “Rotate your shoulders left,” or “Lean sideways toward your left.”
The result is an accessible yoga “exergame” – a video game used for exercise – that allows people without sight to interact verbally with a simulated yoga instructor. Rector and collaborators Julie Kientz, a UW assistant professor in Human Centered Design & Engineering, and Cynthia Bennett, a research assistant in computer science and engineering, believe this can transform a typically visual activity into something that blind people can also enjoy.
“I see this as a good way of helping people who may not know much about yoga to try something on their own and feel comfortable and confident doing it,” Kientz said. “We hope this acts as a gateway to encouraging people with visual impairments to try exercise on a broader scale.”
Each of the six poses has about 30 different commands for improvement based on a dozen rules deemed essential for each yoga position. Rector worked with a number of yoga instructors to put together the criteria for reaching the correct alignment in each pose. The Kinect first checks a person’s core and suggests alignment changes, then moves to the head and neck area, and finally the arms and legs. It also gives positive feedback when a person is holding a pose correctly.
Rector practiced a lot of yoga as she developed this technology. She tested and tweaked each aspect by deliberately making mistakes while performing the exercises. The result is a program that she believes is robust and useful for people who are blind.
“I tested it all on myself so I felt comfortable having someone else try it,” she said.
Rector worked with 16 blind and low-vision people around Washington to test the program and get feedback. Several of the participants had never done yoga before, while others had tried it a few times or took yoga classes regularly. Thirteen of the 16 people said they would recommend the program and nearly everyone would use it again.
The technology uses simple geometry and the law of cosines to calculate angles created during yoga. For example, in some poses a bent leg must be at a 90-degree angle, while the arm spread must form a 160-degree angle. The Kinect reads the angle of the pose using cameras and skeletal-tracking technology, then tells the user how to move to reach the desired angle.
Rector opted to use Kinect software because it’s open source and easily accessible on the market, but she said it does have some limitations in the level of detail with which it tracks movement.
Rector and collaborators plan to make this technology available online so users could download the program, plug in their Kinect and start doing yoga. The team also is pursuing other projects that help with fitness.
How Subtle Movements and Facial Features Could Predict Your Demise
Princeton study shows that health assessments made by medically untrained interviewers can predict mortality of individuals better than those made by physicians or the individuals themselves
Features like the wrinkles on your forehead and the way you move may reflect your overall health and risk of dying, according to recent health research. But do physicians consider such details when assessing patients’ overall health and functioning?
In a survey of approximately 1,200 Taiwanese participants, Princeton University researchers found that interviewers — who were not health professionals but were trained to administer the survey — provided health assessments that were related to a survey participant’s risk of dying, in part because they were attuned to facial expressions, responsiveness and overall agility.
The researchers report in the journal Epidemiology that these assessments were even more accurate predictors of dying than assessments made by physicians or even the individuals themselves. The findings show that survey interviewers, who typically spend a fair amount of time observing participants, can glean important information regarding participants’ health through thorough observations.
"Your face and body reveal a lot about your life. We speculate that a lot of information about a person’s health is reflected in their face, movements, speech and functioning, as well as in the information explicitly collected during interviews," said Noreen Goldman, Hughes-Rogers Professor of Demography and Public Affairs in the Woodrow Wilson School.
Together with lead author of the paper and Princeton Ph.D. candidate Megan Todd, Goldman analyzed data collected by the Social Environment and Biomarkers of Aging Study (SEBAS). This study was designed by Goldman and co-investigator Maxine Weinstein at Georgetown University to evaluate the linkages among the social environment, stress and health. Beginning in 2000, SEBAS conducted extensive home interviews, collected biological specimens and administered medical examinations with middle-aged and older adults in Taiwan. Goldman and Todd used the 2006 wave of this study, which included both interviewer and physician assessments, for their analysis. They also included death registration data through 2011 to ascertain the survival status of those interviewed.
The survey used in the study included detailed questions regarding participants’ health conditions and social environment. Participants’ physical functioning was evaluated through tasks that determined, for example, their walking speed and grip strength. Health assessments were elicited from participants, interviewers and physicians on identical five-point scales by asking “Regarding your/the respondent’s current state of health, do you feel it is excellent (5), good (4), average (3), not so good (2) or poor (1)?”
Participants answered this question near the beginning of the interview, before other health questions were asked. Interviewers assessed the participants’ health at the end of the survey, after administering the questionnaire and evaluating participants’ performance on a set of tasks, such as walking a short distance and getting up and down from a chair. And physicians — who were hired by the study and were not the participants’ primary care physicians — provided their assessments after physical exams and reviews of the participants’ medical histories. (Study investigators did not provide special guidance about how to rate overall health to any group.)
In order to understand the many variables that go into predicting mortality, Goldman and Todd factored into their statistical models such socio-demographic variables as sex, place of residence, education, marital status, and participation in social activities. They also considered chronic conditions, psychological wellbeing (such as depressive symptoms) and physical functioning to account for a fuller picture of health.
"Mortality is easy to measure because we have death records indicating when a person has died," Goldman said. "Overall health, on the other hand, is very complicated to measure but obviously very important for addressing health policy issues."
Two unexpected results emerged from Goldman and Todd’s analysis. The first: physicians’ ratings proved to be weak predictors of survival. “The physicians performed a medical exam equivalent to an annual physical exam, plus an abdominal ultrasound; they have specialized knowledge regarding health conditions,” Goldman explained. “Given access to such information, we anticipated stronger, more accurate predictions of death,” she said. “These results call into question previous studies’ assumptions that physicians’ ‘objective health’ ratings are superior to ‘subjective’ ratings provided by the survey participants themselves.”
In a second surprising finding, the team found that interviewers’ ratings were considerably more powerful for predicting mortality than self-ratings. This is likely, Goldman said, because interviewers considered respondents’ movements, appearance and responsiveness in addition to the detailed health information gathered during the interviews. Also, Goldman posits, interviewer ratings are probably less affected by bias than self-reports.
"The ‘self-rated health’ question is religiously used by health researchers and social scientists, and, although it has been shown to predict mortality, it suffers from many biases. People use it because it’s easy and simple,” Goldman continued. "But the problem with self-rated health is that we have no idea what reference group the respondent is using when evaluating his or her own health. Different ethnic and racial groups respond differently as do varying socioeconomic groups. We need other simple ways to rate individual health instead of relying so heavily on self-rated health."
One way, Goldman suggests, is by including interviewer ratings in surveys along with self-ratings: “This is a straightforward and cost-free addition to a questionnaire that is likely to improve our measurement of health in any population,” Goldman said.
(Source: wws.princeton.edu)
Brain diseases affecting more people and starting earlier than ever before
Professor Colin Pritchard’s latest research published in Public Health Journal has found that the sharp rise of dementia and other neurological deaths in people under 74 cannot be put down to the fact that we are living longer – the rise is because a higher proportion of old people are being affected by such conditions, and what is really alarming, it is starting earlier and affecting people under 55 years.
Of the 10 biggest Western countries the USA had the worst increase in all neurological deaths, men up 66% and women 92% between 1979-2010. The UK was 4th highest, men up 32% and women 48%. In terms of numbers of deaths, in the UK, it was 4,500 and now 6,500, in the USA it was 14,500 now more than 28,500 deaths!
Professor Pritchard of Bournemouth University says: “These statistics are about real people and families, and we need to recognise that there is an ‘epidemic’ that clearly is influenced by environmental and societal changes.”
Tessa Gutteridge, Director YoungDementia UK says that our society needs to learn that dementia is increasingly affecting people from an earlier age: “The lives of an increasing number of families struggling with working-age dementia are made so much more challenging by services which fail to keep pace with their needs and a society which believes dementia to be an illness of old age.”
Bournemouth University researchers, Professor Colin Pritchard and Dr Andrew Mayers, along with the University of Southampton’s Professor David Baldwin show that there are rises in total neurological deaths, including the dementias, which are starting earlier, impacting upon patients, their families and health and social care services, exemplified by an 85% increase in UK Motor Neurone Disease deaths.
The research highlights that there is an alarming ‘hidden epidemic’ of rises in neurological deaths between 1979-2010 of adults (under 74) in Western countries, especially the UK.
Total neurological deaths in both men and women rose significantly in 16 of the countries covered by the research, which is in sharp contrast to the major reductions in deaths from all other causes.
Over the period the UK has the third biggest neurological increase, up 32% in men and 48% in women, whilst women’s neurological deaths rose faster than men’s in most countries.
Professor Pritchard said, “These rises in neurological deaths, with the earlier onset of the dementias, are devastating for families and pose a considerable public health problem. It is NOT that we have more old people but rather more old people have more brain disease than ever before, including Alzheimer’s. For example there are two new British charities, The Young Parkinson’s Society and Young Dementia UK, which are a grass-roots response to these rises. The need for such charities would have been inconceivable a little more than 30 years ago.”
When asked what he thought caused the increases he replied,
“This has to be speculative but it cannot be genetic because the period is too short. Whilst there will be some influence of more elderly people, it does not account for the earlier onset; the differences between countries nor the fact that more women have been affected, as their lives have changed more than men’s over the period, all indicates multiple environmental factors. Considering the changes over the last 30 years – the explosion in electronic devices, rises in background non-ionising radiation- PC’s, micro waves, TV’s, mobile phones; road and air transport up four-fold increasing background petro-chemical pollution; chemical additives to food etc. There is no one factor rather the likely interaction between all these environmental triggers, reflecting changes in other conditions. For example, whilst cancer deaths are down substantially, cancer incidence continues to rise; levels of asthma are un-precedented; the fall in male sperm counts - the rise of auto-immune diseases - all point to life-style and environmental influences. These `statistics’ are about real people and families, and we need to recognise that there is an `epidemic’ that clearly is influenced by environmental and societal changes.”
Scientists reveal drinking champagne could improve memory
New research shows that drinking one to three glasses of champagne a week may counteract the memory loss associated with ageing, and could help delay the onset of degenerative brain disorders, such as dementia.
Scientists at the University of Reading have shown that the phenolic compounds found in champagne can improve spatial memory, which is responsible for recording information about one’s environment, and storing the information for future navigation.
The compounds work by modulating signals in the hippocampus and cortex, which control memory and learning. The compounds were found to favourably alter a number of proteins linked to the effective storage of memories in the brain. Many of these are known to be depleted with age, making memory storage less efficient, and leading to poorer memory in old age and conditions such as dementia. Champagne slows these loses and therefore may help prevent the cognitive losses that occur during typical and atypical brain ageing.
Champagne has relatively high levels of phenolics compared to white wine, deriving predominantly from the two red grapes, Pinot Noir and Pinot Meunier, which are used in its production along with the white grape Chardonnay. It is these phenolic compounds which are believed to be responsible for the beneficial effects of champagne on the brain.
Professor Jeremy Spencer, Department of Food and Nutritional Sciences, University of Reading, said: “These exciting results illustrate for the first time that the moderate consumption of champagne has the potential to influence cognitive functioning, such as memory. Such observations have previously been reported with red wine, through the actions of flavonoids contained within it.
"However, our research shows that champagne, which lacks flavonoids, is also capable of influencing brain function through the actions of smaller phenolic compounds, previously thought to lack biological activity. We encourage a responsible approach to alcohol consumption, and our results suggest that a very low intake of one to two glasses a week can be effective."
Dr. David Vauzour, the researcher on the study, added: “in the near future we will be looking to translate these findings into humans. This has been achieved successfully with other polyphenol-rich foods, such as blueberry and cocoa, and we predict similar outcomes for moderate Champagne intake on cognition in humans.”
Previous research from the University of Reading revealed that two glasses of champagne a day may be good for your heart and circulation and could reduce the risks of suffering from cardiovascular disease and stroke.
The paper is published in Antioxidants and Redox Signalling.
(Image: Getty)
Mental illness associated with heavy cannabis use
People with mental illnesses are more than seven times more likely to use cannabis weekly compared to people without a mental illness, according to researchers from the Centre for Addiction and Mental Health (CAMH) who studied U.S. data.
Cannabis is the most widely used illicit substance globally, with an estimated 203 million people reporting use. Although research has found links between cannabis use and mental illness, exact numbers and prevalence of problem cannabis use had not been investigated.
“We know that people with mental illness consume more cannabis, perhaps partially as a way to self- medicate psychiatric symptoms, but this data showed us the degree of the correlation between cannabis use, misuse, and mental illness,” said Dr. Shaul Lev-ran, Adjunct Scientist at CAMH and Head of Addiction Medicine at the Sheba Medical Center, Israel.
“Based on the number of individuals reporting weekly use, we see that people with mental illness use cannabis at high rates. This can be of concern because it could worsen the symptoms of their mental illness,” said Lev-ran, who conducted the research as a post-doctoral fellow with the Social Aetiology of Mental Illness (SAMI) Training Program at CAMH.
Researchers also found that individuals with mental illness were 10 times more likely to have a cannabis use disorder.
In this new study, published in the journal Comprehensive Psychiatry, CAMH researchers analyzed data from face-to-face interviews with over 43,000 respondents over the age of 18 from the National Epidemiologic Survey on Alcohol and Related Conditions. Using structured questionnaires, the researchers assessed cannabis use as well as various mental illnesses including depression, anxiety, drug and alcohol use disorders and personality disorders, based on criteria from the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV).
Among those will mental illness reporting at least weekly cannabis use, rates of use were particularly elevated for those with bipolar disorder, personality disorders and other substance use disorders.
In total, 4.4 per cent of individuals with a mental illness in the past 12 months reported using cannabis weekly, compared to 0.6 per cent among individuals without any mental illness. Cannabis use disorders occurred among 4 per cent of those with mental illness versus 0.4 per cent among those without.
Researchers also noted that, although cannabis use is generally higher among younger people, the association between mental illness and cannabis use was pervasive across most age groups.
They emphasize the importance of screening for frequent and problem cannabis use among those with mental illness, so that targeted prevention and intervention may be employed.
Sleep Deprivation May Disrupt Your Genes
Far more than just leaving you yawning, a small amount of sleep deprivation disrupts the activity of genes, potentially affecting metabolism and other functions in the human body, a new study suggests.
It’s not clear how your health may be affected by the genetic disruption if you don’t get enough sleep. Still, the research raises the possibility that the effects of too little sleep could have long-lasting effects on your body.
"If people regularly restrict their sleep, it is possible that the disruption that we see … could have an impact over time that ultimately determines their health outcomes as they age in later life," said study co-author Simon Archer, who studies sleep at the University of Surrey, in England.
The study was published online Feb. 25 in the Proceedings of the National Academy of Sciences.
At issue is how a lack of enough sleep affects the human body. While it’s obvious that people get tired when they don’t sleep, scientists have only recently started to understand how sleep deprivation affects more than the brain, said Dr. Charles Czeisler, chief of the division of sleep medicine at Brigham and Women’s Hospital, in Boston. Research has suggested that sleep is important all the way down to the level of cells, said Czeisler, who was not involved in the new study.
For the study, researchers recruited 26 volunteers who spent a week getting a normal amount of sleep (8.5 hours) and a week getting less than normal (5.7 hours). The participants were still able to enter periods of deep sleep.
The researchers then studied the genes of the participants in blood samples and found that numerous genes, including some related to metabolism, became less active.
So what does that mean for the body? “We have no idea,” Archer said, “but these effects are not minor.” They appear to be similar to those that separate normal from abnormal types of tissue in the body, he said.
Archer said the next step will be to investigate how a lack of sleep affects the body in the long term and to figure out whether some kinds of people are more vulnerable to sleep deprivation’s negative effects on health.
For his part, Czeisler praised the study and said it raises the prospect of a blood test that will tell doctors if a patient’s body is being affected because he or she isn’t getting enough sleep. That’s important because substances such as caffeine can hide the effects of lack of sleep so patients don’t realize there’s a problem, he said.
What about the possibility of a pill that mimics the effects of sleep so people don’t have to bother getting some shut-eye in the first place? There’s no evidence to support the idea of such a pill, Czeisler said, although there’s ongoing research into how to improve the quality of sleep that people do manage to get.
(Image: iStock)
An interdisciplinary team of researchers from the University of Texas Medical Branch at Galveston and the University of Houston has found a new way to influence the vital serotonin signaling system — possibly leading to more effective medications with fewer side effects.
Scientists have linked malfunctions in serotonin signaling to a wide range of health issues, everything from depression and addictions to epilepsy and obesity and eating disorders. Much of their attention has focused on complex proteins called serotonin receptors, which are located in the cell membrane. Each receptor has a so-called “active site” specially suited to bond with a serotonin molecule; when that bond is formed, the receptor changes shape, transmitting a signal to the cell’s interior.
Traditional drug discovery efforts target interactions that take place at such active sites. But a receptor’s behavior can also be changed by additional proteins that bind to the receptor at locations quite distant (in molecular terms) from the active site, in a process called “allosteric regulation” — the mechanism examined by the UTMB-UH team for one specific and highly significant kind of serotonin receptor, designated the 5-HT2C.
“This is a whole new way of thinking about this system, targeting these interactions,” said UTMB professor Kathryn Cunningham, senior author of a paper on the research now online in the Journal of Neuroscience. “Basically, we’ve created a new series of molecules and validated that we can use them to change the way the receptor functions both in vitro and in vivo, through an allosteric effect.”
(Image: thedea.org)