Posts tagged health
Articles and news from the latest research reports.
Don’t beat yourself up, you’ll live longer
Brandeis researchers explore the relationship between self-compassion and health
We all have stress in our lives, whether it’s a daily commute, workplace pressures or relationship troubles. But how we deal with that stress could impact our health and longevity.
In a recently published paper in Brain, Behavior and Immunity, Brandeis University researchers report they found a connection between a self-compassionate attitude and lower levels of stress-induced inflammation. The discovery could lead to new techniques to lower stress and improve health.
The paper was authored by psychology professor Nicolas Rohleder, with postdoctoral fellows Juliana Breines and Myriam Thoma, and graduate students Danielle Gianferante, Luke Hanlin and Xuejie Chen.
It’s long known that psychological stress can trigger biological responses similar to the effects of illness or injury, including inflammation. While regulated inflammation can help stave off infection or promote healing, unregulated inflammation can lead to cardiovascular disease, cancer and Alzheimer’s.
Self-compassion describes behaviors such as self-forgiveness or, more colloquially, cutting yourself some slack. A person with high levels of self-compassion may not blame themselves for stress beyond their control or may be more willing to move on from an argument, rather than dwelling on it for days.
To understand the connection between self-compassion and inflammatory responses to stress, Rohleder and his team asked 41 participants to rank their levels of self-compassion. The participants ranked their agreement to statements such as, “I try to be understanding and patient toward aspects of my personality I do not like” and “I’m disapproving and judgmental about my own flaws and inadequacies.”
Then, the participants took one stress test a day for two days and their levels of interleukin-6 (IL-6), an inflammatory agent linked to stress, were recorded before and after each test. After the first stress test, participants with higher self-compassion had significantly lower levels of IL-6.
On the second day, Rohleder and his team found something unexpected. Those with low self-compassion had higher base levels of IL-6 before the test, suggesting that they may have been carrying the stress they experienced the day before.
“The high responses of IL-6 on the first day and the higher baseline levels on the second day suggest that people with low self-compassion are especially vulnerable to the adverse effects of this kind of stress,” Rohleder says.
The research illustrates how easy it is for stress to build over time and how a seemingly small daily stressor, such as traffic, can impact a person’s health if they don’t have the right strategies to deal with it.
“Hopefully, this research can provide more effective ways to cope with stress and reduce disease, not only by relieving negative emotions but by fostering positive ideas of self compassion,” Rohleder says.
Severe obesity on the rise among children in the U.S.
A new study led by a University of North Carolina School of Medicine researcher finds little to cheer about in the fight against childhood obesity, despite a recent report to the contrary.
The study, published online first April 7 in JAMA Pediatrics, found that all classes of obesity in U.S. children have increased over the last 14 years. Perhaps most troubling, the study found an upward trend in the more severe forms of obesity – those in which children have a body mass index (BMI) that is 120 to 140 percent higher than their peers.
“An increase in more severe forms of obesity in children is particularly troubling,” said Asheley Cockrell Skinner, PhD, lead author of the study and assistant professor of pediatrics in the UNC School of Medicine. “Extreme obesity is more clearly associated with heart disease and diabetes risk in children and adolescents, and is more difficult to treat.”
These findings are based on a new analysis of data collected from 26,690 children ages 2-19 from 1999 to 2012 as part of the National Health and Nutrition Examination Survey (NHANES).
(Image: Getty)
Key chocolate ingredients could help prevent obesity, diabetes
Improved thinking. Decreased appetite. Lowered blood pressure. The potential health benefits of dark chocolate keep piling up, and scientists are now homing in on what ingredients in chocolate might help prevent obesity, as well as type-2 diabetes. They found that one particular type of antioxidant in cocoa prevented laboratory mice from gaining excess weight and lowered their blood sugar levels. The report appears in ACS’ Journal of Agricultural & Food Chemistry.
Andrew P. Neilson and colleagues explain that cocoa, the basic ingredient of chocolate, is one of the most flavanol-rich foods around. That’s good for chocolate lovers because previous research has shown that flavanols in other foods such as grapes and tea can help fight weight gain and type-2 diabetes. But not all flavanols, which are a type of antioxidant, are created equal. Cocoa has several different kinds of these compounds, so Neilson’s team decided to tease them apart and test each individually for health benefits.
The scientists fed groups of mice different diets, including high-fat and low-fat diets, and high-fat diets supplemented with different kinds of flavanols. They found that adding one particular set of these compounds, known as oligomeric procyanidins (PCs), to the food made the biggest difference in keeping the mice’s weight down if they were on high-fat diets. They also improved glucose tolerance, which could potentially help prevent type-2 diabetes. “Oligomeric PCs appear to possess the greatest antiobesity and antidiabetic bioactivities of the flavanols in cocoa, particularly at the low doses employed for the present study,” the researchers state.
(Source: acs.org)
Smoking may dull obese women’s ability to taste fat and sugar
Cigarette smoking among obese women appears to interfere with their ability to taste fats and sweets, a new study shows. Despite craving high-fat, sugary foods, these women were less likely than others to perceive these tastes, which may drive them to consume more calories.
M. Yanina Pepino, PhD, assistant professor of medicine at Washington University School of Medicine in St. Louis, and Julie Mennella, PhD, a biopsychologist at the Monell Center in Philadelphia, where the research was conducted, studied four groups of women ages 21 to 41: obese smokers, obese nonsmokers, smokers of normal weight and nonsmokers of normal weight. The women tasted several vanilla puddings containing varying amounts of fat and were asked to rate them for sweetness and creaminess, a measure of fat content.
“Compared with the other three groups, smokers who were obese perceived less creaminess and sweetness,” Pepino said. “They also derived less pleasure from tasting the puddings.”
The findings are published in the April issue of the journal Obesity.
Pepino cautioned that the study only identified associations between smoking and taste rather than definitive reasons why obese smokers were less likely to detect fat and sweetness. But the findings imply that the ability to perceive fat and sweetness — and to derive pleasure from food — is compromised in female smokers who are obese, which could contribute to the consumption of more calories.
“Obese people often crave high-fat foods,” she said. “Our findings suggest that having this intense craving but not perceiving fat and sweetness in food may lead these women to eat more. Since smoking and obesity are risk factors for cardiovascular and metabolic diseases, the additional burden of craving more fats and sugars, while not fully tasting them, could be detrimental to health.”
Interestingly, it was the combination of smoking and obesity that created something of a “double-whammy” because smokers who were not overweight could perceive fat and sweetness that was similar to women who did not smoke.
Previous studies have linked smoking to increased food cravings and greater consumption of fat, regardless of whether a smoker is obese. Studies also have found that smokers tend to have increased waist-to-hip ratios. That is, they tend to be shaped more like apples than pears, another risk factor for heart disease and metabolic problems.
The findings contribute to a growing body of knowledge that challenges the lingering perception that smoking helps a person maintain a healthy weight.
“Women are much more likely than men to take up smoking as an aid to weight control,” Pepino said. “But there is no good evidence showing that it helps maintain a healthy weight over the long term. And in the case of obese women who smoke, it appears the smoking may make things even worse than previously thought.”
(Source: news.wustl.edu)
First UK study of ketamine for people with severe depression
The first UK study of the use of ketamine intravenous infusions in people with treatment-resistant depression has been carried out in an NHS clinic by researchers at Oxford Health NHS Foundation Trust and the University of Oxford.
'Ketamine is a promising new antidepressant which works in a different way to existing antidepressants. We wanted to see whether it would be safe if given repeatedly, and whether it would be practical in an NHS setting. We especially wanted to check that repeated infusions didn't cause cognitive problems,' explains principal investigator Dr Rupert McShane, a consultant psychiatrist at Oxford Health and a researcher in Oxford University's Department of Psychiatry.
The researchers confirmed that ketamine has a rapid antidepressant effect in some patients with severe depression who have not responded to other treatments. These are patients suffering from severe depression which may have lasted years despite multiple antidepressants and talking therapies. Although many patients relapsed within a day or two, 29% had benefit which lasted at least three weeks and 15% took over two months to relapse.
Ketamine did not cause cognitive or bladder side effects when given on up to six occasions, although some people did experience other side effects such as anxiety during the infusion or being sick. The team have now given over 400 infusions to 45 patients and are exploring ways to maintain the effect. They report their findings in the Journal of Psychopharmacology. The study was funded by National Institute for Health Research (NIHR) Research for Patient Benefit Programme.
Researchers discover underlying genetics, marker for stroke, cardiovascular disease
Scientists studying the genomes of nearly 5,000 people have pinpointed a genetic variant tied to an increased risk for stroke, and have also uncovered new details about an important metabolic pathway that plays a major role in several common diseases. Together, their findings may provide new clues to underlying genetic and biochemical influences in the development of stroke and cardiovascular disease, and may also help lead to new treatment strategies.
"Our findings have the potential to identify new targets in the prevention and treatment of stroke, cardiovascular disease and many other common diseases," said Stephen R. Williams, Ph.D., a postdoctoral fellow at the University of Virginia Cardiovascular Research Center and the University of Virginia Center for Public Health Genomics, Charlottesville.
Dr. Williams, Michele Sale, Ph.D., associate professor of medicine, Brad Worrall, M.D., professor of neurology and public health sciences, all at the University of Virginia, and their team reported their findings March 20, 2014 in PLoS Genetics. The investigators were supported by the National Human Genome Research Institute (NHGRI) Genomics and Randomized Trials Network (GARNET) program (www.genome.gov/27541119).
Stroke is the fourth leading cause of death and a major cause of adult disability in this country, yet its underlying genetics have been difficult to understand. Numerous genetic and environmental factors can contribute to a person having a stroke. “Our goals were to break down the risk factors for stroke,” Dr. Williams said.
The researchers focused on one particular biochemical pathway called the folate one-carbon metabolism (FOCM) pathway. They knew that abnormally high blood levels of the amino acid homocysteine are associated with an increased risk of common diseases such as stroke, cardiovascular disease and dementia. Homocysteine is a breakdown product of methionine, which is part of the FOCM pathway. The same pathway can affect many important cellular processes, including the methylation of proteins, DNA and RNA. DNA methylation is a mechanism that cells use to control which genes are turned on and off, and when.
But clinical trials of homocysteine-lowering therapies have not prevented disease, and the genetics underlying high homocysteine levels - and methionine metabolism gone awry - are not well defined.
Dr. Williams and his colleagues conducted genome-wide association studies of participants from two large long-term projects: the Vitamin Intervention for Stroke Prevention (VISP), a trial looking at ways to prevent a second ischemic stroke, and the Framingham Heart Study (FHS), which has followed the cardiovascular health and disease in a general population for decades. They also measured methionine metabolism - the ability to convert methionine to homocysteine - in both groups. In all, they studied 2,100 VISP participants and 2,710 FHS subjects.
In a genome-wide association study, researchers scan the genome to identify specific genomic variants associated with a disease. In this case, the scientists were trying to identify variants associated with a trait - the ability to metabolize methionine into homocysteine.
Investigators identified variants in five genes in the FOCM pathway that were associated with differences in a person’s ability to convert methionine to homocysteine. They found that among the five genes, one - the ALDH1L1 gene - was also strongly associated with stroke in the Framingham study. When the gene is not working properly, it has been associated with a breakdown in a normal cellular process called programmed cell death, and cancer cell survival.
They also made important discoveries about the methionine-homocysteine process. “GNMT produces a protein that converts methionine to homocysteine. Of the five genes that we identified, it was the one most significantly associated with this process,” Dr. Williams said. “The analyses suggest that differences in GNMT are the major drivers behind the differences in methionine metabolism in humans.”
"It’s striking that the genes are in the same pathway, so we know that the genomic variants affecting that pathway contribute to the variability in disease and risk that we’re seeing," he said. "We may have found how genetic information controls the regulation of GNMT."
The group determined that the five genes accounted for 6 percent of the difference in individuals’ ability to process methionine into homocysteine among those in the VISP trial. The genes also accounted for 13 percent of the difference in those participants in the FHS, a remarkable result given the complex nature of methionine metabolism and its impact on cerebrovascular risk. In many complex diseases, genomic variants often account for less than 5 percent of such differences.
"This is a great example of the kinds of successful research efforts coming out of the GARNET program," said program director Ebony Madden, Ph.D. "GARNET scientists aim to identify variants that affect treatment response by doing association studies in randomized trials. These results show that variants in genes are associated with the differences in homocysteine levels in individuals."
The association of the ALDH1L1 gene variant with stroke is just one example of how the findings may potentially lead to new prevention efforts, and help develop new targets for treating stroke and heart disease, Dr. Williams said.
"As genome sequencing becomes more widespread, clinicians may be able to determine if a person’s risk for abnormally high levels of homocysteine is elevated," he said. "Changes could be made to an individual’s diet because of a greater risk for stroke and cardiovascular disease."
The investigators plan to study the other four genes in the pathway to try to better understand their potential roles in stroke and cardiovascular disease risk.
Children’s preferences for sweeter and saltier tastes are linked to each other
Scientists from the Monell Chemical Senses Center have found that children who most prefer high levels of sweet tastes also most prefer high levels of salt taste and that, in general, children prefer sweeter and saltier tastes than do adults. These preferences relate not only to food intake but also to measures of growth and can have important implications for efforts to change children’s diets.
Many illnesses of modern society are related to poor food choices. Because children consume far more sugar and salt than recommended, which contributes to poor health, understanding the biology behind children’s preferences for these tastes is a crucial first step to reducing their intake.
"Our research shows that the liking of salty and sweet tastes reflects in part the biology of the child," said study lead author Julie Mennella, PhD, a biopsychologist at Monell. Biology predisposes us to like and consume calorie-rich sweet foods and sodium-rich salty foods, and this is especially true for children. "Growing children’s heightened preferences for sweet and salty tastes make them more vulnerable to the modern diet, which differs from the diet of our past, when salt and sugars were once rare and expensive commodities."
In the study, published online at PLOS ONE, Mennella and colleagues tested 108 children between 5 and 10 years old, and their mothers, for salt and sweet taste preferences. The same testing method was used for both children and their mothers, who tasted broth and crackers that varied in salt content, and sugar water and jellies that varied in sugar content. The method, developed by Mennella and her colleagues at Monell, scientifically determines taste preferences, even for very young children, by having them compare two different levels of a taste, pick their favorite, and then compare that favorite with another, over and again until the most favorite is identified.
Mennella and colleagues also had mothers and children list foods and beverages they consumed in the past 24 hours, from which daily sodium, calorie, and added sugar intakes were estimated. Subjects then gave a saliva sample, which was genotyped for a sweet receptor gene, and a urine sample to measure levels of Ntx, a marker for bone growth. Weight, height, and percent body fat were measured for all subjects.
Analyses of all these data showed that not only were sweet and salty preferences correlated in children, and higher overall than those in adults, but also children’s taste preferences related to measures of growth and development: children who were tall for their age preferred sweeter solutions, and children with higher amounts of body fat preferred saltier soups. There was also some indication that higher sweet liking related to spurts in bone growth, but that result needs confirmation in a larger group of children.
Sweet and salty preferences were correlated in adults as well. And in adults, but not in children, sweet receptor genotype was related to the most preferred level of sweetness. “There are inborn genetic differences that affect the liking for sweet by adults,” says collaborator Danielle Reed, PhD, “but for children, other factors – perhaps the current state of growth – are stronger influences than genetics.”
Both children and adults who preferred higher levels of salt in food also reported consuming more dietary salt in the past 24 hours, but no such relationship was found between sweet preferences and sugar intake. This difference may reflect parents exerting greater control in their children’s diet for added sugar than for added salt. Or it could reflect increased use of non-nutritive sweeteners in foods geared for children – in other words, the sweetness of some foods doesn’t reflect their sugar content.
Current intakes of sodium and added sugars among US children are well in excess of recommendations. For almost all 2- to 8-year-olds, added sugars account for more than half of their discretionary calories (130 total discretionary calories are allowed for children of this age). For 4- to 13-year-olds, sodium intake is more than twice adequate levels (1200-1500 mg/day is allowed for children of this age). The children studied by Mennella and colleagues, two-thirds of whom were overweight or obese, also consumed twice adequate levels of sodium, and their added sugar intake averaged almost 20 teaspoons, or 300 calories, each day.
Guidelines from leading authorities, including the World Health Organization, American Heart Association, U.S. Department of Agriculture, and Institute of Medicine, recommend significantly cutting sugar and salt intake for children, but this can be a daunting task. Commenting on the implications of her research, lead author Mennella noted, “The present findings reveal that the struggle parents have in modifying their children’s diets to comply with recommendations appears to have a biological basis.”
Understanding the basic biology that drives the desire for sweet and salty tastes in children illustrates their vulnerability to the current food environment. But on a positive note, Mennella observed, “it also paves the way toward developing more insightful and informed strategies for promoting healthy eating that meet the particular needs of growing children.”
Scientists discover hormone released after exercise can ‘predict’ biological age
Scientists from Aston University have discovered a potential molecular link between Irisin, a recently identified hormone released from muscle after bouts of exercise, and the ageing process.
Irisin, which is naturally present in humans, is capable of reprograming the body’s fat cells to burn energy instead of storing it. This increases the metabolic rate and is thought to have potential anti-obesity effects which in turn could help with conditions such as type-2 diabetes.
The research team led by Dr James Brown have proven a significant link exists between Irisin levels in the blood and a biological marker of ageing called telomere length. Telomeres are small regions found at the end of chromosomes that shorten as cells within the body replicate. Short telomere length has been linked to many age-related diseases including cancer, heart disease and Alzheimer’s disease.
Using a population of healthy, non-obese individuals, the team has shown those individuals who had higher levels of Irisin were found to have longer telomeres. The finding provides a potential molecular link between keeping active and healthy ageing with those having higher Irisin levels more ‘biological young’ than those with lower levels of the hormone.
Dr James Brown from Aston’s Research Centre for Healthy Ageing, said; “Exercise is known to have wide ranging benefits, from cardiovascular protection to weight loss. Recent research has suggested that exercise can protect people from both physical and mental decline with ageing. Our latest findings now provide a potential molecular link between keeping active and a healthy ageing process.”
The Aston Research Centre for Healthy Ageing takes a multidisciplinary approach to successful ageing by asking how technological, therapeutic and psychosocial strategies can be employed to understand and arrest age-related decline and degeneration.
Racism May Accelerate Aging in African American Men
A new University of Maryland-led study reveals that racism may impact aging at the cellular level. Researchers found signs of accelerated aging in African American men who reported high levels of racial discrimination and who had internalized anti-Black attitudes. Findings from the study, which is the first to link racism-related factors and biological aging, are published in the American Journal of Preventive Medicine.
Racial disparities in health are well-documented, with African Americans having shorter life expectancy, and a greater likelihood of suffering from aging-related illnesses at younger ages compared to whites. Accelerated aging at the biological level may be one mechanism linking racism and disease risk.
“We examined a biomarker of systemic aging, known as leukocyte telomere length,” explained Dr. David H. Chae, assistant professor of epidemiology at UMD’s School of Public Health and the study’s lead investigator. Shorter telomere length is associated with increased risk of premature death and chronic disease such as diabetes, dementia, stroke and heart disease. “We found that the African American men who experienced greater racial discrimination and who displayed a stronger bias against their own racial group had the shortest telomeres of those studied,” Chae explained.
Telomeres are repetitive sequences of DNA capping the ends of chromosomes, which shorten progressively over time – at a rate of approximately 50-100 base pairs annually. Telomere length is variable, shortening more rapidly under conditions of high psychosocial and physiological stress. “Telomere length may be a better indicator of biological age, which can give us insight into variations in the cumulative ‘wear and tear’ of the organism net of chronological age,” said Chae. Among African American men with stronger anti-black attitudes, investigators found that average telomere length was 140 base pairs shorter in those reporting high vs. low levels of racial discrimination; this difference may equate to 1.4 to 2.8 years chronologically.
Participants in the study were 92 African American men between 30-50 years of age. Investigators asked them about their experiences of discrimination in different domains, including work and housing, as well as in getting service at stores or restaurants, from the police, and in other public settings. They also measured racial bias using the Black-White Implicit Association Test. This test gauges unconscious attitudes and beliefs about race groups that people may be unaware of or unwilling to report.
Even after adjusting for participants’ chronological age, socioeconomic factors, and health-related characteristics, investigators found that the combination of high racial discrimination and anti-black bias was associated with shorter telomeres. On the other hand, the data revealed that racial discrimination had little relationship with telomere length among those holding pro-black attitudes. “African American men who have more positive views of their racial group may be buffered from the negative impact of racial discrimination,” explained Chae. “In contrast, those who have internalized an anti-black bias may be less able to cope with racist experiences, which may result in greater stress and shorter telomeres.”
The findings from this study are timely in light of regular media reports of racism facing African American men. “Stop-and-frisk policies, and other forms of criminal profiling such as ‘driving or shopping while black’ are inherently stressful and have a real impact on the health of African Americans,” said Chae. Researchers found that racial discrimination by police was most commonly reported by participants in the study, followed by discrimination in employment. In addition, African American men are more routinely treated with less courtesy or respect, and experience other daily hassles related to racism.
Chae indicated the need for additional research to replicate findings, including larger studies that follow participants over time. “Despite the limitations of our study, we contribute to a growing body of research showing that social toxins disproportionately impacting African American men are harmful to health,” Chae explained. “Our findings suggest that racism literally makes people old.”
(Image: Shutterstock)
Higher vitamin D levels in pregnancy could help babies become stronger
Children are likely to have stronger muscles if their mothers had a higher level of vitamin D in their body during pregnancy, according to new research from the Medical Research Council Lifecourse Epidemiology Unit (MRC LEU) at the University of Southampton.
Low vitamin D status has been linked to reduced muscle strength in adults and children, but little is known about how variation in a mother’s status during pregnancy affects her child.
Low vitamin D concentrations are common among young women in the UK, and although women are recommended to take an additional 10μg/day of vitamin D in pregnancy, supplementation is often not taken up.
In the research, published in the January edition of the Journal of Clinical Endocrinology and Metabolism, vitamin D levels were measured in 678 mothers in the later stages of pregnancy.
When the children were four years old, grip strength and muscle mass were measured. Results showed that the higher the levels of vitamin D in the mother, the higher the grip strength of the child, with an additional, but less pronounced association between mother’s vitamin D and child’s muscle mass.
Lead researcher Dr Nicholas Harvey, Senior Lecturer at the MRC LEU at the University of Southampton, comments: “These associations between maternal vitamin D and offspring muscle strength may well have consequences for later health; muscle strength peaks in young adulthood before declining in older age and low grip strength in adulthood has been associated with poor health outcomes including diabetes, falls and fractures. It is likely that the greater muscle strength observed at four years of age in children born to mothers with higher vitamin D levels will track into adulthood, and so potentially help to reduce the burden of illness associated with loss of muscle mass in old age.”
The 678 women who took part in the study are part of the Southampton Women’s Survey, one of the largest and best characterised such studies globally.
Professor Cyrus Cooper, Professor of Rheumatology and Director of the MRC LEU at the University of Southampton, who oversaw this work, added: “This study forms part of a larger programme of research at the MRC Lifecourse Epidemiology Unit and University of Southampton in which we are seeking to understand how factors such as diet and lifestyle in the mother during pregnancy influence a child’s body composition and bone development. This work should help us to design interventions aimed at optimising body composition in childhood and later adulthood and thus improve the health of future generations.”
(Source: southampton.ac.uk)