Sleep is vital to associating emotion with memory

February 22, 2021

Science Daily/University of Michigan

When you slip into sleep, it's easy to imagine that your brain shuts down, but University of Michigan research suggests that groups of neurons activated during prior learning keep humming, tattooing memories into your brain.

U-M researchers have been studying how memories associated with a specific sensory event are formed and stored in mice. In a study conducted prior to the coronavirus pandemic and recently published in Nature Communications, the researchers examined how a fearful memory formed in relation to a specific visual stimulus.

They found that not only did the neurons activated by the visual stimulus keep more active during subsequent sleep, sleep is vital to their ability to connect the fear memory to the sensory event.

Previous research has shown that regions of the brain that are highly active during intensive learning tend to show more activity during subsequent sleep. But what was unclear was whether this "reactivation" of memories during sleep needs to occur in order to fully store the memory of newly learned material.

"Part of what we wanted to understand was whether there is communication between parts of the brain that are mediating the fear memory and the specific neurons mediating the sensory memory that the fear is being tied to. How do they talk together, and must they do so during sleep? We would really like to know what's facilitating that process of making a new association, like a particular set of neurons, or a particular stage of sleep," said Sara Aton, senior author of the study and a professor in the U-M Department of Molecular, Cellular and Developmental Biology. "But for the longest time, there was really no way to test this experimentally."

Now, researchers have the tools to genetically tag cells that are activated by an experience during a specific window of time. Focusing on a specific set of neurons in the primary visual cortex, Aton and the study's lead author, graduate student Brittany Clawson, created a visual memory test. They showed a group of mice a neutral image, and expressed genes in the visual cortex neurons activated by the image.

To verify that these neurons registered the neutral image, Aton and her team tested whether they could instigate the memory of the image stimulus by selectively activating the neurons without showing them the image. When they activated the neurons and paired that activation with a mild foot shock, they found that their subjects would subsequently be afraid of visual stimuli that looked similar to the image those cells encode. They found the reverse also to be true: after pairing the visual stimulus with a foot shock, their subjects would subsequently respond with fear to reactivating the neurons.

"Basically, the precept of the visual stimulus and the precept of this completely artificial activation of the neurons generated the same response," Aton said.

The researchers found that when they disrupted sleep after they showed the subjects an image and had given them a mild foot shock, there was no fear associated with the visual stimulus. Those with unmanipulated sleep learned to fear the specific visual stimulus that had been paired with the foot shock.

"We found that these mice actually became afraid of every visual stimulus we showed them," Aton said. "From the time they go to the chamber where the visual stimuli are presented, they seem to know there's a reason to feel fear, but they don't know what specifically they're afraid of."

This likely shows that, in order for them to make an accurate fear association with a visual stimulus, they have to have sleep-associated reactivation of the neurons encoding that stimulus in the sensory cortex, according to Aton. This allows a memory specific to that visual cue to be generated.The researchers think that at the same time, that sensory cortical area must communicate with other brain structures, to marry the sensory aspect of the memory to the emotional aspect.

Aton says their findings could have implications for how anxiety and post-traumatic stress disorder are understood.

"To me this is kind of a clue that says, if you're linking fear to some very specific event during sleep, sleep disruption may affect this process. In the absence of sleep, the brain seems to manage processing the fact that you are afraid, but you may be unable to link that to what specifically you should be afraid of," Aton said. "That specification process may be one that goes awry with PTSD or generalized anxiety."

https://www.sciencedaily.com/releases/2021/02/210222164216.htm

How the 'noise' in our brain influences our behavior

Neural variability provides an essential basis for how we perceive the world and react to it

February 17, 2021

Science Daily/Max Planck Institute for Human Development

The brain's neural activity is irregular, changing from one moment to the next. To date, this apparent "noise" has been thought to be due to random natural variations or measurement error. However, researchers at the Max Planck Institute for Human Development have shown that this neural variability may provide a unique window into brain function. In a new Perspective article out now in the journal Neuron, the authors argue that researchers need to focus more on neural variability to fully understand how behavior emerges from the brain.

When neuroscientists investigate the brain, its activity seems to vary all the time. Sometimes activity is higher or lower, rhythmic or irregular. Whereas averaging brain activity has served as a standard way of visualizing how the brain "works," the irregular, seemingly random patterns in neural signals have often been disregarded. Strikingly, such irregularities in neural activity appear regardless of whether single neurons or entire brain regions are assessed. Brains simply always appear "noisy," prompting the question of what such moment-to-moment neural variability may reveal about brain function.

Across a host of studies over the past 10 years, researchers from the Lifespan Neural Dynamics Group (LNDG) at the Max Planck Institute for Human Development and the Max Planck UCL Centre for Computational Psychiatry and Ageing Research have systematically examined the brain's "noise," showing that neural variability has a direct influence on behavior. In a new Perspective article published in the journal Neuron, the LNDG in collaboration with the University of Lübeck highlights what is now substantial evidence supporting the idea that neural variability represents a key, yet under-valued dimension for understanding brain-behavior relationships. "Animals and humans can indeed adapt successfully to environmental demands, but how can such behavioral success emerge in the face of neural variability? We argue that neuroscientists must grapple with the possibility that behavior may emerge because of neural variability, not in spite of it," says Leonhard Waschke, first author of the article and LNDG postdoctoral fellow.

A recent LNDG study published in the journal eLife exemplifies the direct link between neural variability and behavior. Participants' brain activity was measured via electroencephalography (EEG) while they responded to faint visual targets. When people were told to detect as many visual targets as possible, neural variability generally increased, whereas it was downregulated when participants were asked to avoid mistakes. Crucially, those who were better able to adapt their neural variability to these task demands performed better on the task. "The better a brain can regulate its 'noise,' the better it can process unknown information and react to it. Traditional ways of analyzing brain activity simply disregard this entire phenomenon." says LNDG postdoctoral fellow Niels Kloosterman, first author of this study and co-author of the article in Neuron.

The LNDG continues to demonstrate the importance of neural variability for successful human behavior in an ongoing series of studies. Whether one is asked to process a face, remember an object, or solve a complex task, the ability to modulate moment-to-moment variability seems to be required for optimal cognitive performance. "Neuroscientists have seen this 'noise' in the brain for decades but haven't understood what it means. A growing body of work by our group and others highlights that neural variability may indeed serve as an indispensable signal of behavioral success in its own right. With the increasing availability of tools and approaches to measure neural variability, we are excited that such a hypothesis is now immediately testable," says Douglas Garrett, Senior Research Scientist and LNDG group leader. In the next phases of their research, the group plans to examine whether neural variability and behavior can be optimized through brain stimulation, behavioral training, or medication.

https://www.sciencedaily.com/releases/2021/02/210217134848.htm

Study suggests role of sleep in healing traumatic brain injuries

Technique developed at OHSU measures brain's waste-clearance system through MRIs

March 12, 2021

Science Daily/Oregon Health & Science University

Sound sleep plays a critical role in healing traumatic brain injury, a new study of military veterans suggests.

The study, published in the Journal of Neurotrauma, used a new technique involving magnetic resonance imaging developed at Oregon Health & Science University. Researchers used MRI to evaluate the enlargement of perivascular spaces that surround blood vessels in the brain. Enlargement of these spaces occurs in aging and is associated with the development of dementia.

Among veterans in the study, those who slept poorly had more evidence of these enlarged spaces and more post-concussive symptoms.

"This has huge implications for the armed forces as well as civilians," said lead author Juan Piantino, M.D., MCR, assistant professor of pediatrics (neurology) in the OHSU School of Medicine and Doernbecher Children's Hospital. "This study suggests sleep may play an important role in clearing waste from the brain after traumatic brain injury -- and if you don't sleep very well, you might not clean your brain as efficiently."

Piantino, a physician-scientist with OHSU's Papé Family Pediatric Research Institute, studies the effects of poor sleep on recovery after traumatic brain injuries.

The new study benefited from a method of analyzing MRIs developed by study co-author Daniel Schwartz and Erin Boespflug, Ph.D., under the direction of Lisa Silbert, M.D., M.C.R., professor of neurology in the OHSU School of Medicine. The technique measures changes in the brain's perivascular spaces, which are part of the brain's waste clearance system known as the glymphatic system.

"We were able to very precisely measure this structure and count the number, location and diameter of channels," Piantino said.

Co-author Jeffrey Iliff, Ph.D., professor of psychiatry and behavioral sciences and of neurology at the University of Washington and a researcher at the VA Puget Sound Health Care System, has led scientific research into the glymphatic system and its role in neurodegenerative conditions such as Alzheimer's disease. During sleep, this brain-wide network clears away metabolic proteins that would otherwise build up in the brain.

The study used data collected from a group of 56 veterans enrolled by co-authors Elaine Peskind, M.D., and Murray Raskind, M.D., at the Mental Illness Research, Education and Clinical Center at the VA Puget Sound between 2011 and 2019.

"Imagine your brain is generating all this waste and everything is working fine," Piantino said. "Now you get a concussion. The brain generates much more waste that it has to remove, but the system becomes plugged."

Piantino said the new study suggests the technique developed by Silbert could be useful for older adults.

"Longer term, we can start thinking about using this method to predict who is going to be at higher risk for cognitive problems including dementia," he said.

The study is the latest in a growing body of research highlighting the importance of sleep in brain health.

Improving sleep is a modifiable habit that can be improved through a variety of methods, Piantino said, including better sleep hygiene habits such as reducing screen time before bed. Improving sleep is a focus of research of other OHSU scientists, including Piantino's mentor, Miranda Lim, M.D., Ph.D., associate professor of neurology, medicine and behavioral neuroscience in the OHSU School of Medicine.

"This study puts sleep at the epicenter of recovery in traumatic brain injury," Piantino said.

https://www.sciencedaily.com/releases/2021/03/210312155435.htm

High rates of depression, anxiety, PTSD worldwide among health workers during COVID-19

Sixty five-study analysis includes research published in English and Chinese

March 10, 2021

Science Daily/PLOS

A new systematic review of 65 studies from around the world involves a total of 97,333 health care workers and finds that 1 in 5 have experienced depression, anxiety, and/or PTSD during the ongoing COVID-19 pandemic. Yufei Li, Nathaniel Scherer, and colleagues at the London School of Hygiene & Tropical Medicine, U.K., present these findings in the open-access journal PLOS ONE on March 10.

The pandemic has posed significant challenges for health care workers, with many fearing for their own safety while facing a high workload and limited psychological support. Previous analyses of data from multiple studies have revealed high rates of depression, anxiety, and PTSD among health care workers during the pandemic. However, those reviews did not adequately address the many relevant studies conducted in China, where the first COVID-19 outbreak occurred.

To address that gap, Li, Scherer, and colleagues carried out a systematic search of studies in both English and Chinese that were conducted from December 2019 to August 2020 and addressed prevalence of mental disorders in health care workers. They identified 65 suitable studies from 21 countries, involving a total of 97,333 health care workers.

By pooling and statistically analyzing data from all 65 studies, the researchers estimated that 21.7 percent of the health care workers involved in the studies have experienced depression during the pandemic, 22.1 percent anxiety, and 21.5 percent PTSD. Studies conducted in the Middle East showed the highest pooled rates of depression (34.6 percent) and anxiety (28.9 percent).

These findings suggest that the COVID-19 pandemic has significantly impacted the mental health of health care workers. For comparison, the World Health Organization estimates that 4.4 percent of the entire world population experience depression, and 3.6 percent experience anxiety disorders, including PTSD. However, those estimates were determined through different methods and prior to the pandemic.

Nonetheless, the authors note, the new findings could help inform policy and initiatives to provide urgently needed psychological support to health care workers.

The authors add: "This systematic review and meta-analysis provides, to date, the most comprehensive synthesis of depression, anxiety and PTSD prevalence amongst health care workers during the COVID-19 pandemic, with the unique inclusion of publications in both English and Chinese."

https://www.sciencedaily.com/releases/2021/03/210310150402.htm

Study identifies potential link between Soldiers exposed to blasts, Alzheimer's

February 25, 2021

Science Daily/U.S. Army Research Laboratory

Research shows that Soldiers exposed to shockwaves from military explosives are at a higher risk for developing Alzheimer's disease -- even those that don't have traumatic brain injuries from those blasts. A new Army-funded study identifies how those blasts affect the brain.

Researchers at the University of North Carolina at Pembroke in collaboration with the U.S. Army Combat Capabilities Development Command, now known as DEVCOM, the Army Research Laboratory, and the National Institutes of Health found that the mystery behind blast-induced neurological complications when traumatic damage is undetected may be rooted in distinct alterations to the tiny connections between neurons in the hippocampus, the part of the brain particularly involved in memory encoding and social behavior.

The research published in Brain Pathology, the medical journal of the International Society of Neuropathology, was funded by the lab's Army Research Office.

"Blasts can lead to debilitating neurological and psychological damage but the underlying injury mechanisms are not well understood," said Dr. Frederick Gregory, program manager, ARO. "Understanding the molecular pathophysiology of blast-induced brain injury and potential impacts on long-term brain health is extremely important to understand in order to protect the lifelong health and well-being of our service members."

The research team tested slices of rat hippocampus by exposing the healthy tissue to controlled military blast waves. In the experimental brain explants (tissue slices maintained alive in culture dishes), the rapid blast waves produced by the detonated military explosives led to selective reductions in components of brain connections needed for memory, and the distinct electrical activity from those neuronal connections was sharply diminished.

The research showed that the blast-induced effects were evident among healthy neurons with subtle synaptic pathology, which may be an early indicator of Alzheimer's-type pathogenesis occurring independent of overt brain damage.

"This finding may explain those many blast-exposed individuals returning from war zones with no detectable brain injury, but who still suffer from persistent neurological symptoms, including depression, headaches, irritability and memory problems," said Dr. Ben Bahr, the William C. Friday distinguished professor of Molecular Biology and Biochemistry at UNC-Pembroke.

The researchers believe that the increased risk of developing Alzheimer's disease is likely rooted in the disruption of neuronal communication instigated by blast exposures.

"Early detection of this measurable deterioration could improve diagnoses and treatment of recurring neuropsychiatric impediments, and reduce the risk of developing dementia and Alzheimer's disease later in life," Bahr said.

https://www.sciencedaily.com/releases/2021/02/210225112922.htm

Changes in mouth bacteria after drinking beetroot juice may promote healthy aging

March 30, 2021

Science Daily/University of Exeter

Drinking beetroot juice promotes a mix of mouth bacteria associated with healthier blood vessels and brain function, according to a new study of people aged 70-80.

Beetroot -- and other foods including lettuce, spinach and celery -- are rich in inorganic nitrate, and many oral bacteria play a role in turning nitrate to nitric oxide, which helps to regulate blood vessels and neurotransmission (chemical messages in the brain).

Older people tend to have lower nitric oxide production, and this is associated with poorer vascular (blood vessel) and cognitive (brain) health.

In the new study, by the University of Exeter, 26 healthy older people took part in two ten-day supplementation periods: one with nitrate-rich beetroot juice and another with nitrate-free placebo juice, which they drank twice a day.

The results showed higher levels of bacteria associated with good vascular and cognitive health, and lower levels of bacteria linked to disease and inflammation.

Systolic blood pressure dropped on average by five points (mmHg) after drinking the beetroot juice.

"We are really excited about these findings, which have important implications for healthy ageing," said lead author Professor Anni Vanhatalo, of the University of Exeter.

"Previous studies have compared the oral bacteria of young and older people, and healthy people compared to those with diseases, but ours is the first to test nitrate-rich diet in this way.

"Our findings suggest that adding nitrate-rich foods to the diet -- in this case via beetroot juice -- for just ten days can substantially alter the oral microbiome (mix of bacteria) for the better.

"Maintaining this healthy oral microbiome in the long term might slow down the negative vascular and cognitive changes associated with ageing."

The researchers ran tests to identify clusters (or "modules") of oral bacteria that tend to thrive together in similar conditions.

A module (Prevotella-Veillonella) that has been associated with inflammation was reduced after nitrate supplementation, including a decrease of Clostridium difficile (which can infect the bowel and cause diarrhea).

Professor Vanhatalo stressed that more research is needed to confirm the findings and see whether similar effects are found in other groups.

"Our participants were healthy, active older people with generally good blood pressure," she said. "Dietary nitrate reduced their blood pressure on average, and we are keen to find out whether the same would happen in other age groups and among people in poorer health.

"We are working with colleagues in the University of Exeter Medical School to investigate interactions between the oral bacteria and cognition to better understand the how diet could be used to delay cognitive decline in older age."

Much research has been conducted into the benefits of a healthy gut microbiome, but far less is known about the oral microbial community, which plays a crucial role in "activating" the nitrate from a vegetable-rich diet.

https://www.sciencedaily.com/releases/2021/03/210330121231.htm

Should you take fish oil? Depends on your genotype

March 25, 2021

Science Daily/University of Georgia

Fish oil supplements are a billion-dollar industry built on a foundation of purported, but not proven, health benefits. Now, new research from a team led by a University of Georgia scientist indicates that taking fish oil only provides health benefits if you have the right genetic makeup.

The study, led by Kaixiong Ye and published in PLOS Genetics, focused on fish oil (and the omega-3 fatty acids it contains) and its effect on triglycerides, a type of fat in the blood and a biomarker for cardiovascular disease.

"We've known for a few decades that a higher level of omega-3 fatty acids in the blood is associated with a lower risk of heart disease," said Ye, assistant professor of genetics in the Franklin College of Arts and Sciences. "What we found is that fish oil supplementation is not good for everyone; it depends on your genotype. If you have a specific genetic background, then fish oil supplementation will help lower your triglycerides. But if you do not have that right genotype, taking a fish oil supplement actually increases your triglycerides."

Ye's team, including first author and graduate student Michael Francis, examined four blood lipids (fats) -- high-density lipoprotein, low-density lipoprotein, total cholesterol and triglycerides -- that are biomarkers for cardiovascular disease. The data for their sample of 70,000 individuals was taken from UK Biobank, a large-scale cohort study collecting genetic and health information from half a million participants.

The team divided the sample into two groups, those taking fish oil supplements (about 11,000) and those not taking fish oil supplements. Then they performed a genome-wide scan for each group, testing for 8 million genetic variants to compare. After running over 64 million tests, their results revealed a significant genetic variant at gene GJB2. Individuals with the AG genotype who took fish oil decreased their triglycerides. Individuals with the AA genotype who took fish oil slightly increased their triglycerides. (A third possible genotype, GG, was not evident in enough study volunteers to draw conclusions.)

Determining your genotype is not as far-fetched as it sounds, thanks to direct-to-consumer genetic testing companies. Companies may not report that specific genetic variant yet, but a tech-savvy consumer should be able to download the raw data and look at the specific position to discover the genotype, according to Ye. The ID for the variant is rs112803755 (A>G).

The study's findings may also shed light on previous trials, most of which found that fish oil provides no benefit in preventing cardiovascular disease.

"One possible explanation is that those clinical trials didn't consider the genotypes of the participants," Ye said. "Some participants may benefit, and some may not, so if you mix them together and do the analysis, you do not see the impact."

Now that Ye has identified a specific gene that can modify an individual's response to fish oil supplementation, his next step will be directly testing the effects of fish oil on cardiovascular disease.

"Personalizing and optimizing fish oil supplementation recommendations based on a person's unique genetic composition can improve our understanding of nutrition," he said, "and lead to significant improvements in human health and well-being."

https://www.sciencedaily.com/releases/2021/03/210325115253.htm

Green leafy vegetables essential for muscle strength

March 24, 2021

Science Daily/Edith Cowan University

Eating just one cup of leafy green vegetables every day could boost muscle function, according to new Edith Cowan University (ECU) research.

The study, published today in the Journal of Nutrition, found that people who consumed a nitrate-rich diet, predominantly from vegetables, had significantly better muscle function of their lower limbs.

Poor muscle function is linked to greater risk of falls and fractures and is considered a key indicator of general health and wellbeing.

Researchers examined data from 3,759 Australians taking part in Melbourne's Baker Heart and Diabetes Institute AusDiab study over a 12-year period. They found those with the highest regular nitrate consumption had 11 per cent stronger lower limb strength than those with the lowest nitrate intake. Up to 4 per cent faster walking speeds were also recorded.

Lead researcher Dr Marc Sim from ECU's Institute for Nutrition Research said the findings reveal important evidence for the role diet plays in overall health.

"Our study has shown that diets high in nitrate-rich vegetables may bolster your muscle strength independently of any physical activity," he said.

"Nevertheless, to optimise muscle function we propose that a balanced diet rich in green leafy vegetables in combination with regular exercise, including weight training, is ideal."

Muscle function is vital for maintaining good overall health, especially bone strength later in life.

"With around one in three Australians aged over 65 suffering a fall each year, it's important to find ways of preventing these events and their potentially serious consequences," said Dr Sim.

Go for green

While leafy greens may be some of our least favourite vegetables, they could be the most important, according to Dr Sim.

The research found nitrate-rich vegetables, such as lettuce, spinach, kale and even beetroot, provided the greatest health benefits.

"Less than one in ten Australians eat the recommended five to six serves of vegetables per day," Dr Sim said.

"We should be eating a variety of vegetables every day, with at least one of those serves being leafy greens to gain a range of positive health benefits for the musculoskeletal and cardiovascular system."

"It's also better to eat nitrate-rich vegetables as part of a healthy diet rather than taking supplements. Green leafy vegetables provide a whole range of essential vitamins and minerals critical for health."

Building knowledge

The study, a collaboration with Deakin University's Institute of Physical Activity and Nutrition and the Baker Heart and Diabetes Institute, builds on Dr Sim's previous research into nitrate and muscle function in older women.

It also adds to growing evidence linking vegetables with cardiovascular health, including a recent ECU study into cruciferous vegetables and blood vessel health.

Dr Sim said the next step of his research will be exploring strategies to increase leafy green vegetable consumption in the general population.

"We are currently recruiting for the MODEL Study, which examines how knowledge of disease can be used to prompt people in making long-term improvements to their diet and exercise," said Dr Sim.

https://www.sciencedaily.com/releases/2021/03/210324132309.htm

Consumption of added sugar doubles fat production

March 16, 2021

Science Daily/University of Zurich

Sugar is added to many common foodstuffs, and people in Switzerland consume more than 100 grams of it every day. The high calorie content of sugar causes excessive weight and obesity, and the associated diseases. But does too much sugar have any other harmful effects if consumed regularly? And if so, which sugars in particular?

Even moderate amounts of sugar increase fat synthesis

Researchers at the University of Zurich (UZH) and the University Hospital Zurich (USZ) have been investigating these questions. Compared to previous studies, which mainly examined the consumption of very high amounts of sugar, their results show that even moderate amounts lead to a change in the metabolism of test participants. "Eighty grams of sugar daily, which is equivalent to about 0,8 liters of a normal soft drink, boosts fat production in the liver. And the overactive fat production continues for a longer period of time, even if no more sugar is consumed," says study leader Philipp Gerber of the Department of Endocrinology, Diabetology and Clinical Nutrition.

Ninety-four healthy young men took part in the study. Every day for a period of seven weeks, they consumed a drink sweetened with different types of sugar, while the control group did not. The drinks contained either fructose, glucose or sucrose (table sugar which is a combination of fructose and glucose). The researchers then used tracers (labeled substances that can be traced as they move through the body) to analyze the effect of the sugary drinks on the lipid metabolism.

Fructose and sucrose double fat production beyond food intake

Overall, the participants did not consume more calories than before the study, as the sugary drink increased satiety and they therefore reduced their calorie intake from other sources. Nevertheless, the researchers observed that fructose has a negative effect: "The body's own fat production in the liver was twice as high in the fructose group as in the glucose group or the control group -- and this was still the case more than twelve hours after the last meal or sugar consumption," says Gerber. Particularly surprising was that the sugar we most commonly consume, sucrose, boosted fat synthesis slightly more than the same amount of fructose. Until now, it was thought that fructose was most likely to cause such changes.

Development of fatty liver or diabetes more likely

Increased fat production in the liver is a significant first step in the development of common diseases such as fatty liver and type-2 diabetes. From a health perspective, the World Health Organization recommends limiting daily sugar consumption to around 50 grams or, even better, 25 grams. "But we are far off that mark in Switzerland," says Philipp Gerber. "Our results are a critical step in researching the harmful effects of added sugars and will be very significant for future dietary recommendations."

https://www.sciencedaily.com/releases/2021/03/210316100709.htm

Stress reduction as a path to eating less fast food

Intervention's effect of lowering stress linked to dietary improvement

March 11, 2021

Science Daily/Ohio State University

Overweight low-income mothers of young kids ate fewer fast-food meals and high-fat snacks after participating in a study -- not because researchers told them what not to eat, but because the lifestyle intervention being evaluated helped lower the moms' stress, research suggests.

The 16-week program was aimed at preventing weight gain by promoting stress management, healthy eating and physical activity. The methods to get there were simple steps tucked into lessons on time management and prioritizing, many demonstrated in a series of videos featuring mothers like those participating in the study.

"We used the women's testimonies in the videos and showed their interactions with their families to raise awareness about stressors. After watching the videos, a lot of intervention participants said, 'This is the first time I've realized I am so stressed out' -- because they've lived a stressful life," said Mei-Wei Chang, lead author of the study and associate professor of nursing at The Ohio State University.

"Many of these women are aware of feeling impatient, and having head and neck pain and trouble sleeping -- but they don't know those are signs of stress."

An analysis of the study data showed that the women's lowered perceived stress after participating in the intervention was the key factor influencing their eventual decrease in consumption of high-fat and fast foods.

"It's not that these women didn't want to eat healthier," Chang said. "If you don't know how to manage stress, then when you are so stressed out, why would you care about what you eat?"

The research is published in a recent issue of the journal Nutrients.

The 338 participants, overweight or obese moms between the ages of 18 and 39, were recruited from the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC), which serves low-income mothers and children up to age 5. Those eligible for the program must have an annual household income no higher than 185 percent of the federal poverty line.

Chang said these women are likely to face a number of challenges that could cause them stress: financial difficulties, living in run-down neighborhoods, frequent moves, unstable romantic relationships and households bustling with little kids. It's also common for this population to retain 10 or more pounds of pregnancy weight after childbirth and risk life-long obesity and potential problems for themselves and new babies if they become pregnant again.

During the trial, the 212 participants randomized into the intervention group watched a total of 10 videos in which women like them gave unscripted testimonials about healthy eating and food preparation, managing their stress and being physically active. Participants also dialed in to 10 peer support group teleconferences over the course of the study.

Chang and colleagues previously reported that as a group, the women in the intervention arm of the study were more likely to have reduced their fat consumption than women in a comparison group who were given print materials about lifestyle change.

This newer analysis showed that the intervention's lessons alone did not directly affect that change in diet. When the researchers assessed the potential role of stress as a mediator, the indirect effect of the intervention -- reducing participants' perceived stress -- was associated with less consumption of high-fat foods, including fast food. A 1-point reduction in the scale measuring stress was linked to a nearly 7% reduction in how frequently the women ate high-fat foods.

The intervention focused on showing the women examples of how they could achieve a healthier and less stressful lifestyle rather than telling them what they had to change.

"I learned a lot from those women," Chang said. "Everything needs to be practical and applicable to daily life -- anytime, anywhere."

Some examples: Comparing a bag of chips to a bag of apples -- the chips might be half the price, but they supply far fewer family snacks. Or using a household responsibility chart to assign tasks to young children, and encouraging moms to reward kids with a hug or individual attention when they follow the instructions. And taking deep breaths to counter the feeling of being overwhelmed.

When it came to stress management, the researchers focused on advising the women to shift their thinking, and not to blame themselves when things go wrong, rather than to take on solving the problems that caused them stress.

"We raised their awareness about stressors in their lives, and unfortunately a lot of these problems are not within their control," Chang said. "So we teach them ways to control their negative emotions -- remember that this is temporary, and you can get through it. And give them confidence to look to the future."

The videos from the intervention are now part of WIC's continuing education series for mothers. This work was supported by the National Institutes of Health. Co-authors included Duane Wegener from Ohio State and Roger Brown from the University of Wisconsin-Madison.

https://www.sciencedaily.com/releases/2021/03/210311185957.htm

Two servings of fish per week can help prevent recurrent heart disease

March 8, 2021

Science Daily/McMaster University

An analysis of several large studies involving participants from more than 60 countries, spearheaded by researchers from McMaster University, has found that eating oily fish regularly can help prevent cardiovascular disease (CVD) in high-risk individuals, such as those who already have heart disease or stroke.

The critical ingredient is omega-3 fatty acids, which researchers found was associated with a lower risk of major CVD events such as heart attacks and strokes by about a sixth in high-risk people who ate two servings of fish rich in omega-3 each week.

"There is a significant protective benefit of fish consumption in people with cardiovascular disease," said lead co-author Andrew Mente, associate professor of research methods, evidence, and impact at McMaster and a principal investigator at the Population Health Research Institute.

No benefit was observed with consumption of fish in those without heart disease or stroke.

"This study has important implications for guidelines on fish intake globally. It indicates that increasing fish consumption and particularly oily fish in vascular patients may produce a modest cardiovascular benefit."

Mente said people at low risk for cardiovascular disease can still enjoy modest protection from CVD by eating fish rich in omega-3, but the health benefits were less pronounced than those high-risk individuals.

The study was published in JAMA Internal Medicine on March 8.

The findings were based on data from nearly 192,000 people in four studies, including about 52,000 with CVD, and is the only study conducted on all five continents. Previous studies focused mainly on North America, Europe, China and Japan, with little information from other regions.

"This is by far the most diverse study of fish intake and health outcomes in the world and the only one with sufficient numbers with representation from high, middle and low income countries from all inhabited continents of the world," said study co-lead Dr. Salim Yusuf, professor of medicine at the Michael G. DeGroote School of Medicine and executive director of the PHRI.

https://www.sciencedaily.com/releases/2021/03/210308131709.htm

Eating more refined grains increases risk of heart attack, early death

The researchers examined diets from diverse populations in low, middle and high-income countries.

February 19, 2021

Science Daily/Simon Fraser University

A new study published in The British Medical Journal by researchers including SFU health sciences professor Scott Lear found consuming a high number of refined grains, such as croissants and white bread, is associated with a higher risk of major cardiovascular disease, stroke and early death.

The Prospective Urban Rural Epidemiology (PURE) study has been examining diets from diverse populations in low-, middle- and high-income countries around the world. Over 16 years of analysis of 137,130 participants in 21 countries, including Canada, the researchers found the intake of refined grains and added sugars have greatly increased over the years.

Grains were categorized into three groups: refined grains, whole grains and white rice. Refined grains included goods made with refined (e.g. white) flour, including white bread, pasta/noodles, breakfast cereals, crackers, and bakery products/desserts containing refined grains. Whole grains included whole grain flours (e.g. buckwheat) and intact or cracked whole grains (eg. steel cut oats).

The study found that having more than seven servings of refined grains per day was associated with a 27 per cent greater risk for early death, 33 percent greater risk for heart disease and 47 per cent greater risk for stroke.

"This study re-affirms previous work indicating a healthy diet includes limiting overly processed and refined foods," says Lear.

No significant adverse health effects were found with consuming whole grains or white rice.

The study suggests eating whole grain foods like brown rice and barley, and having fewer cereal grains and refined wheat products. Reducing one's overall consumption of refined grains and having better quality carbohydrates is essential for optimal health outcomes.

https://www.sciencedaily.com/releases/2021/02/210219155857.htm

Study links prolonged sedentary time to distractibility in adults with obesity, overweight

February 17, 2021

Science Daily/University of Illinois at Urbana-Champaign, News Bureau

Scientists used accelerometers to track daily activity levels for a week in 89 adults with obesity or overweight and, in a series of tests, measured their ability to multitask and maintain their attention despite distractions. The study revealed that individuals who spent more sedentary time in bouts lasting 20 minutes or more were less able to overcome distractions.

Reported in the International Journal of Obesity, the research adds to the evidence linking sedentary behaviors and cognition, said University of Illinois Urbana-Champaign kinesiology and community health professor Dominika Pindus, who led the work on the paper.

"Several studies have examined the relationship between different types of sedentary behaviors such as TV viewing and cognitive functions in children and adults," Pindus said. "The relationships they observed varied with the type of sedentary behavior. These studies primarily measured sedentary behaviors during leisure time."

The research found that regularly sitting for extended periods is linked to increased mortality and cardiovascular disease, Pindus said. People who do not engage in at least 60 minutes per day of moderate-to-vigorous physical activity and sit for eight hours or more have an increased health risk. Other studies suggest that bouts of prolonged sitting lasting 20 minutes or more negatively affect levels of blood sugar after a meal.

"Few studies, however, have examined the relationship between prolonged sedentary time and cognitive functions," Pindus said. To address this gap in research, she and her colleagues focused on the associations between objectively measured, prolonged sedentary time and cognition in adults 25-45 years old with obesity or overweight.

"We know from previous research that people with obesity or overweight don't do as well on certain types of cognitive tasks," Pindus said. "These tasks engage executive functions -- cognitive functions that are important for reasoning and staying focused on a goal."

Some studies have found that long-term physical activity interventions in preadolescent children or older adults can improve those functions.

"But we don't have much data on how prolonged sedentary time is linked to executive functions in working-age people with obesity or overweight," she said. "If we can show how sedentary time and physical activity in everyday life relate to executive functions in those individuals, we may be able to design more targeted lifestyle interventions to improve cognition in this population."

The researchers collected baseline information for all participants, tested their cognitive ability and calculated each person's body mass index and percent body fat. Participants wore accelerometers on their waists during waking hours for seven days. They also completed cognitive tasks and measures of brain function in a laboratory setting.

"We used EEG recordings to measure electrical potentials that are generated in the brain while participants engaged in tasks that challenged them to focus, ignore distractions and flexibly switch attention between tasks," Pindus said. A controller connected to a computer allowed participants to respond to problems while the speed and accuracy of their responses was recorded.

A statistical analysis of participants' sedentariness in relation to their speed and accuracy on a task that measures distractibility found a relationship between the two, Pindus said.

"Our key finding was that people who spent more time in prolonged sedentary bouts were more easily distracted," she said.

More research is needed to determine how the structure of a person's sedentary time influences cognition, Pindus said.

"If you make sure to break up your sitting time with brief bouts of physical activity, could that reduce how distracted you will be?" she said. "And if it does, what is driving this effect? This is something we want to explore."

https://www.sciencedaily.com/releases/2021/02/210217132335.htm

Women 'risk' grey hair to feel authentic

April 12, 2021

Science Daily/University of Exeter

Many women "risk" allowing natural grey hair to show in order to feel authentic, a new study shows.

Researchers from the University of Exeter surveyed women who chose not to dye their grey hair, and found a "conflict" between looking natural and being seen as competent.

Participants in the study -- mostly from English-speaking countries -- belonged to online groups whose members allow their natural grey hair to show, and the researchers noted "solidarity and sisterhood" among these women.

"We are all constrained by society's norms and expectations when it comes to appearance, but expectations are more rigorous for women -- especially older women," said lead author Vanessa Cecil, of the University of Exeter.

"The 'old woman' is an undesirable character in Western societies, being seen as incompetent or unpleasant -- if she is seen at all.

"In our study, we wanted to understand why some women choose natural grey hair.

"In the face of impossible standards to be natural and remain youthful forever, these women are doing what they can to retain status.

"Although many reported negative consequences such as being ignored or treated as less competent, they also felt happier to be 'flying my natural flag'.

"We also found that women chose to compensate for going grey by using other beauty practices -- so embracing grey isn't the same as embracing looking old.

"Grey-haired and youthfully glamorous is one thing, but in Western societies it's still not OK to look old."

Responses from the 80 participants, members of two Facebook groups about transitioning to natural grey hair, suggested the key trade-off was between authenticity and being seen as competent.

Women reported being shamed -- including by family and friends -- for being too natural ("let oneself go") but also wanted to avoid looking as if they have tried too hard to conceal their age ("mutton dressed as lamb").

Those who were supported by partners, family and friends had an "easier time" of the transition to grey, Cecil said.

Many women have chosen natural grey hair during COVID lockdowns -- both because hairdressers have been closed and due to spending less time in public, including at work.

"This appears to have accelerated a shift that was already happening, with more and more women choosing not to dye their hair," Cecil said.

https://www.sciencedaily.com/releases/2021/04/210412114815.htm

Stress from work and social interactions put women at higher coronary heart disease risk

April 9, 2021

Science Daily/Drexel University

Psychosocial stress -- typically resulting from difficulty coping with challenging environments -- may work synergistically to put women at significantly higher risk of developing coronary heart disease, according to a study by researchers at Drexel University's Dornsife School of Public Health, recently published in the Journal of the American Heart Association.

The study specifically suggests that the effects of job strain and social strain -- the negative aspect of social relationships -- on women is a powerful one-two punch. Together they are associated with a 21% higher risk of developing coronary heart disease. Job strain occurs when a woman has inadequate power in the workplace to respond to the job's demands and expectations.

The study also found that high-stress life events, such as a spouse's death, divorce/separation or physical or verbal abuse, as well as social strain, were each independently linked with a 12% and 9% higher risk of coronary heart disease, respectively.

The Drexel study used data from a nationally representative sample of 80,825 postmenopausal women from the Women's Health Initiative Observational Study, which tracked participants from 1991 to 2015, to find better methods of preventing cancer, heart disease and osteoporosis in women. In the current follow-up study, Drexel researchers evaluated the effect of psychosocial stress from job strain, stressful life events and social strain (through a survey), and associations among these forms of stress, on coronary heart disease.

Nearly 5% of the women developed coronary heart disease during the 14-year, seven-month study. Adjusting for age, time at a job, and socioeconomic characteristics, high-stress life events were associated with a 12% increased coronary heart disease risk, and high social strain was associated with a 9% increased risk of coronary heart disease. Work strain was not independently associated with coronary heart disease.

Coronary heart disease, the leading cause of death in the United States, occurs with the heart's arteries become narrow and cannot bring sufficient oxygenated blood to the heart. The latest work builds on earlier studies linking psychosocial stress to coronary heart disease by finding out how job strain and social strain work together to compound disease risk.

"The COVID-19 pandemic has highlighted ongoing stresses for women in balancing paid work and social stressors. We know from other studies that work strain may play a role in developing CHD, but now we can better pinpoint the combined impact of stress at work and at home on these poor health outcomes," said senior author Yvonne Michael, ScD, SM, an associate professor in the Dornsife School of Public Health. "My hope is that these findings are a call for better methods of monitoring stress in the workplace and remind us of the dual-burden working women face as a result of their unpaid work as caregivers at home ."

The study's authors say that future studies should look at the effects of shift work on coronary heart disease and explore the effects of job demands according to gender.

"Our findings are a critical reminder to women, and those who care about them, that the threat of stress to human health should not go ignored," said lead author Conglong Wang, PhD, a recent Dornsife graduate who conducted the research while at Drexel. "This is particularly pertinent during the stressors caused by a pandemic."

https://www.sciencedaily.com/releases/2021/04/210409124746.htm

Gut microbiota in Cesarean-born babies catches up

April 1, 2021

Science Daily/University of Gothenbur

Infants born by cesarean section have a relatively meager array of bacteria in the gut. But by the age of three to five years they are broadly in line with their peers. This is shown by a study that also shows that it takes a remarkably long time for the mature intestinal microbiota to get established.

Fredrik Bäckhed, Professor of Molecular Medicine at Sahlgrenska Academy, University of Gothenburg, has been heading this research. The study, conducted in collaboration with Halland County Hospital in Halmstad, is now published in the journal Cell Host & Microbe.

Professor Bäckhed and his group have previously demonstrated that the composition of children's intestinal microbiota is affected by their mode of delivery and diet. In the current study, the researchers examined in detail how the composition of intestinal bacteria in 471 children born at the hospital in Halmstad had developed.

The first fecal sample was collected when each child was a newborn infant. Thereafter, sampling took place at 4 months, 12 months, 3 years and 5 years. The scientists were thus able to follow the successive incorporation of various bacteria into the children's gut microbiota.

At birth, the infant's intestine has already been colonized by bacteria and other microorganisms. During the first few years of life, the richness of species steadily increases. What is now emerging is a considerably more detailed picture of this developmental trajectory.

One key conclusion is that the intestinal microbiota forms an ecosystem that takes a long time to mature. Even at 5 years of age, the system is incomplete. The maturation process can look very different from one child to another, and take varying lengths of time.

At the age of 4 months, the gut microbiota in the cesarean-born infants was less diverse compared with vaginally born infants. However, when the children were 3 and 5 years the microbiota diversity and composition had caught up and were largely normalized intestinal microbiota.

"Our findings show that the gut microbota is a dynamic organ, and future studies will have to show whether the early differences can affect the cesarean children later in life," Bäckhed says.

"It's striking that even at the age of 5 years, several of the bacteria that are important components of the intestinal microbiota in adults are missing in the children," he continues.

This indicates that the intestine is a complex and dynamic environment where bacteria create conditions for one another's colonization.

According to the researchers, the current study has broadened our understanding of how humans interact with the trillions of bacteria contained in our bodies, and of how these bacteria become established.

Lisa Olsson, a researcher at the University of Gothenburg and one of the first authors, adds:

"Children learn skills like walking and talking at different rates, and it turns out that the same applies to the maturity of the gut microbiota."

Fredrik Bäckhed again:

"By investigating and understanding how the intestinal microbiota develops in healthy children, we may get a reference point to explorie if the microbiota may contribute to disease in future studies," he concludes.

https://www.sciencedaily.com/releases/2021/04/210401112526.htm

Moderate daily caffeine intake during pregnancy may lead to smaller birth size

March 25, 2021

Science Daily/NIH/Eunice Kennedy Shriver National Institute of Child Health and Human Development

Pregnant women who consumed the caffeine equivalent of as little as half a cup of coffee a day on average had slightly smaller babies than pregnant women who did not consume caffeinated beverages, according to a study by researchers at the National Institutes of Health. The researchers found corresponding reductions in size and lean body mass for infants whose mothers consumed below the 200 milligrams of caffeine per day -- about two cups of coffee -- believed to increase risks to the fetus. Smaller birth size can place infants at higher risk of obesity, heart disease and diabetes later in life.

The researchers were led by Katherine L. Grantz, M.D., M.S., of the Division of Intramural Population Health Research at NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development. The study appears in JAMA Network Open.

"Until we learn more, our results suggest it might be prudent to limit or forego caffeine-containing beverages during pregnancy," Dr. Grantz said. "It's also a good idea for women to consult their physicians about caffeine consumption during pregnancy."

Previous studies have linked high caffeine consumption (more than 200 milligrams of caffeine per day) during pregnancy to infants being small for their gestational age (stage of pregnancy) or at risk for intrauterine growth restriction -- being in the lowest 10th percentile for infants of the same gestational age. However, studies on moderate daily caffeine consumption (200 milligrams or less) during pregnancy have produced mixed results. Some have found similar elevated risks for low birth weight and other poor birth outcomes, while others have found no such links. The current study authors noted that many of the earlier studies did not account for other factors that could influence infant birth size, such as variation in caffeine content of different beverages and maternal smoking during pregnancy.

For their study, the authors analyzed data on more than 2,000 racially and ethnically diverse women at 12 clinical sites who were enrolled from 8 to 13 weeks of pregnancy. The women were non-smokers and did not have any health problems before pregnancy. From weeks 10 to 13 of pregnancy, the women provided a blood sample that was later analyzed for caffeine and paraxanthine, a compound produced when caffeine is broken down in the body. The women also reported their daily consumption of caffeinated beverages (coffee, tea, soda and energy drinks) for the past week -- once when they enrolled and periodically throughout their pregnancies.

Compared to infants born to women with no or minimal blood levels of caffeine, infants born to women who had the highest blood levels of caffeine at enrollment were an average of 84 grams lighter at birth (about 3 ounces), were .44 centimeters shorter (about .17 inches), and had head circumferences .28 centimeters smaller (about .11 inches).

Based on the women's own estimates of the beverages they drank, women who consumed about 50 milligrams of caffeine a day (equivalent to a half cup of coffee) had infants 66 grams (about 2.3 ounces) lighter than infants born to non-caffeine consumers. Similarly, infants born to the caffeine consumers also had thigh circumferences .32 centimeters smaller (about .13 inches).

The researchers noted that caffeine is believed to cause blood vessels in the uterus and placenta to constrict, which could reduce the blood supply to the fetus and inhibit growth. Similarly, researchers believe caffeine could potentially disrupt fetal stress hormones, putting infants at risk for rapid weight gain after birth and for later life obesity, heart disease and diabetes.

The authors concluded that their findings suggest that even moderate caffeine consumption may be associated with decreased growth of the fetus.

https://www.sciencedaily.com/releases/2021/03/210325150122.htm

Pregnant women show robust immune response to COVID vaccines, pass antibodies to newborns

March 25, 2021

Science Daily/Massachusetts General Hospital

In the largest study of its kind to date, researchers at Massachusetts General Hospital, Brigham and Women's Hospital and the Ragon Institute of MGH, MIT and Harvard have found the new mRNA COVID-19 vaccines to be highly effective in producing antibodies against the SARS-CoV-2 virus in pregnant and lactating women. They also demonstrated the vaccines confer protective immunity to newborns through breastmilk and the placenta.

The study, published in the American Journal of Obstetrics and Gynecology (AJOG), looked at 131 women of reproductive age (84 pregnant, 31 lactating and 16 non-pregnant), all of whom received one of the two new mRNA vaccines: Pfizer/BioNTech or Moderna. The vaccine-induced titers -- or antibody levels -- were equivalent in all three groups. Reassuringly, side effects after vaccination were rare and comparable across the study participants.

"This news of excellent vaccine efficacy is very encouraging for pregnant and breastfeeding women, who were left out of the initial COVID-19 vaccine trials," says Andrea Edlow, MD, MSc, a maternal-fetal medicine specialist at MGH, director of the Edlow Lab in the Vincent Center for Reproductive Biology and co-senior author of the new study. "Filling in the information gaps with real data is key -- especially for our pregnant patients who are at greater risk for complications from COVID-19. This study also highlights how eager pregnant and lactating individuals are to participate in research."

According to the Centers for Disease Control and Prevention, individuals who are pregnant are more likely to become severely ill with COVID-19, require hospitalization, intensive care or ventilation -- and may be at increased risk for adverse pregnancy outcomes. The team also compared vaccination-induced antibody levels to those induced by natural infection with COVID-19 in pregnancy, and found significantly higher levels of antibodies from vaccination.

Vaccine-generated antibodies were also present in all umbilical cord blood and breastmilk samples taken from the study, showing the transfer of antibodies from mothers to newborns.

"We now have clear evidence the COVID vaccines can induce immunity that will protect infants," says Galit Alter, PhD, core member of the Ragon Institute and co-senior author of the study. "We hope this study will catalyze vaccine developers to recognize the importance of studying pregnant and lactating individuals, and include them in trials. The potential for rational vaccine design to drive improved outcomes for mothers and infants is limitless, but developers must realize that pregnancy is a distinct immunological state, where two lives can be saved simultaneously with a powerful vaccine. We look forward to studying all vaccine platforms in pregnancy as they become available."

The study was also able to provide insight into potential differences between the immune response elicited by the Pfizer vaccine compared to the Moderna vaccine, finding the levels of mucosal (IgA) antibodies were higher after the second dose of Moderna compared to the second dose of Pfizer.

"This finding is important for all individuals, since SARS-CoV-2 is acquired through mucosal surfaces like the nose, mouth and eyes," says Kathryn Gray, MD, PhD, an obstetrician at Brigham and Women's Hospital and a first author of the paper. "But it also holds special importance for pregnant and lactating women because IgA is a key antibody present in breastmilk."

https://www.sciencedaily.com/releases/2021/03/210325150127.htm

Parental burnout hits individualist Western countries hardest

March 18, 2021

Science Daily/Université catholique de Louvain

Does the incidence of parental burnout depend on a country's culture? This question was at the heart of the first international study on the subject for which hundreds of scientists in 42 countries mobilised. In other words, the global scientific community is worried about family stress-induced parental burnout. A high level of stress in the family can lead to parental exhaustion. Such suffering has serious consequences for both parents and children.

'We worked in close collaboration with scientists from all the cultures involved,' UCLouvain researchers and study initiators and coordinators Isabelle Roskam and Moïra Mikolajczak explained in a statement. 'They were the only ones capable of collecting data in their countries, guaranteeing their validity and interpreting them correctly. Such exceptional collaboration deserves to be highlighted.'

The study's findings are categorical: rich, individualistic Western countries, which on average have few children, are the most affected by the phenomenon. Culture, rather than socio-economic and demographic differences between countries, plays a predominant role in parental burnout. 'Prevalence varies greatly from one culture and country to another,' Prof. Roskam explains. 'We could have hypothesised that it would be the same everywhere but that the reasons for exhaustion would be different.' This is not the case.

Published in Affective Science, the study shows that the values of individualism in Western countries can subject parents to higher levels of stress. The results force us to question ourselves in a context where the mantra of "every one for oneself" is spreading all over the world.

'Our individualistic countries cultivate a cult of performance and perfectionism,' says Prof. Roskam, a parental burnout specialist. 'Parenthood in these countries is a very solitary activity, unlike in African countries, for example, where the entire village is involved in raising children.' These poorer countries, which often have many children, are more collectivist. This dimension seems to protect against parental burnout. In addition, Western individualism is exacerbated by the current health crisis: families find themselves isolated and cut off from their social relations.

What measures can be taken to prevent stress in parenting? 'The first would be to revive in our cultures the dimension of sharing and mutual aid among parents within a community,' Prof. Roskam says. 'And abandon the cult of the perfect parent and gain some perspective on all the parenting advice out there in order to choose what works for you.'

Thanks to the study consortium's collective dynamics, their work opens up many avenues for future intercultural investigations. Until now, all studies on parental burnout focused on personal factors. However, parents affected by this syndrome exercise their parenting in a particular cultural context. It is important to take this into account when treating symptoms.

https://www.sciencedaily.com/releases/2021/03/210318085604.htm

In women, higher body fat may protect against heart disease death

March 16, 2021

Science Daily/University of California - Los Angeles Health Sciences

A new UCLA study shows that while men and women who have high muscle mass are less likely to die from heart disease, it also appears that women who have higher levels of body fat -- regardless of their muscle mass -- have a greater degree of protection than women with less fat.

The researchers analyzed national health survey data collected over a 15-year period and found that heart disease-related death in women with high muscle mass and high body fat was 42% lower than in a comparison group of women with low muscle mass and low body fat. However, women who had high muscle mass and low body fat did not appear have a significant advantage over the comparison group.

Among men, on the other hand, while having high muscle mass and high body fat decreased their risk by 26% (compared to those with low muscle mass and low body fat), having high muscle mass and low body fat decreased their risk by 60%.

The American Heart Association estimates that 5 million men and 3 million women have heart attacks annually. Yet despite this wide gender gap and an overall decrease in heart attack-related deaths for both men and women over the past 50 years, an equal number of men and women still die from heart disease.

In addition, mortality among women over those five decades has fallen at a slower rate than for men, and the incidence of heart attacks appears to be increasing among women between the ages of 35 and 54. Recent research has also found that women have significantly higher levels of risk factors associated with adverse heart disease than men.

The researchers analyzed body composition data from the National Health and Nutrition Examination Survey 1999-2004 and cardiovascular disease data from the National Health and Nutrition Examination Survey 1999-2014. They evaluated 11,463 individuals aged 20 and older, who were then divided into four body-composition groups: low muscle mass and low body fat, low muscle and high fat, high muscle and low fat, and high muscle and high fat. Heart disease-related mortality rates where then calculated for each of these groups.

The findings highlight the importance of recognizing physiological differences between women and men when considering body composition and the risk of death from heart disease, particularly when it comes to how differences in body fat may modify that risk.

The research also underscores the need to develop sex-appropriate guidelines with respect to exercise and nutrition as preventive strategies against the development of cardiovascular disease. Even with the current emphasis by health experts on reducing fat to lower disease risk, it may be important for women to focus more on building muscle mass than losing weight, the study authors say.

https://www.sciencedaily.com/releases/2021/03/210316183651.htm