Healthy lifestyle can help prevent depression -- and new research may explain why

September 11, 2023

Science Daily/University of Cambridge

A healthy lifestyle that involves moderate alcohol consumption, a healthy diet, regular physical activity, healthy sleep and frequent social connection, while avoiding smoking and too much sedentary behaviour, reduces the risk of depression, new research has found.

In research published today in Nature Mental Health, an international team of researchers, including from the University of Cambridge and Fudan University, looked at a combination of factors including lifestyle factors, genetics, brain structure and our immune and metabolic systems to identify the underlying mechanisms that might explain this link.

According to the World Health Organization, around one in 20 adults experiences depression, and the condition poses a significant burden on public health worldwide. The factors that influence the onset of depression are complicated and include a mixture of biological and lifestyle factors.

To better understand the relationship between these factors and depression, the researchers turned to the UK Biobank, a biomedical database and research resource containing anonymised genetic, lifestyle and health information about its participants.

By examining data from almost 290,000 people -- of whom 13,000 had depression -- followed over a nine-year period, the team was able to identify seven healthy lifestyle factors linked with a lower risk of depression. These were:

• moderate alcohol consumption

• healthy diet

• regular physical activity

• healthy sleep

• never smoking

• low-to-moderate sedentary behaviour

• frequent social connection

Of all of these factors, having a good night's sleep -- between seven and nine hours a night -- made the biggest difference, reducing the risk of depression, including single depressive episodes and treatment-resistant depression, by 22%.

Frequent social connection, which in general reduced the risk of depression by 18%, was the most protective against recurrent depressive disorder.

Moderate alcohol consumption decreased the risk of depression by 11%, healthy diet by 6%, regular physical activity by 14%, never smoking by 20%, and low-to-moderate sedentary behaviour by 13%.

Based on the number of healthy lifestyle factors an individual adhered to, they were assigned to one of three groups: unfavourable, intermediate, and favourable lifestyle. Individuals in the intermediate group were around 41% less likely to develop depression compared to those in the unfavourable lifestyle, while those in the favourable lifestyle group were 57% less likely.

The team then examined the DNA of the participants, assigning each a genetic risk score. This score was based on the number of genetic variants an individual carried that have a known link to risk of depression. Those with the lowest genetic risk score were 25% less likely to develop depression when compared to those with the highest score -- a much smaller impact than lifestyle.

In people at high, medium, and low genetic risk for depression, the team further found that a healthy lifestyle can cut the risk of depression. This research underlines the importance of living a healthy lifestyle for preventing depression, regardless of a person's genetic risk.

Professor Barbara Sahakian, from the Department of Psychiatry at the University of Cambridge, said: "Although our DNA -- the genetic hand we've been dealt -- can increase our risk of depression, we've shown that a healthy lifestyle is potentially more important.

"Some of these lifestyle factors are things we have a degree control over, so trying to find ways to improve them -- making sure we have a good night's sleep and getting out to see friends, for example -- could make a real difference to people's lives."

To understand why a healthy lifestyle might reduce the risk of depression, the team studied a number of other factors.

First off, they examined MRI brain scans from just under 33,000 participants and found a number of regions of the brain where a larger volume -- more neurons and connections -- was linked to a healthy lifestyle. These included the pallidum, thalamus, amygdala and hippocampus.

Next, the team looked for markers in the blood that indicated problems with the immune system or metabolism (how we process food and produce energy). Among those markers found to be linked to lifestyle were the C-reactive protein, a molecule produced in the body in response to stress, and triglycerides, one of the primary forms of fat that the body uses to store energy for later.

These links are supported by a number of previous studies. For example, exposure to stress in life can affect how well we are able to regulate blood sugar, which may lead to a deterioration of immune function and accelerate age-related damage to cells and molecules in the body. Poor physical activity and lack of sleep can damage the body's ability to respond to stress. Loneliness and lack of social support have been found to increase the risk of infection and increase markers of immune deficiency.

The team found that the pathway from lifestyle to immune and metabolic functions was the most significant. In other words, a poorer lifestyle impacts on our immune system and metabolism, which in turn increases our risk of depression.

Dr Christelle Langley, also from the Department of Psychiatry at the University of Cambridge, said: "We're used to thinking of a healthy lifestyle as being important to our physical health, but it's just as important for our mental health. It's good for our brain health and cognition, but also indirectly by promoting a healthier immune system and better metabolism."

Professor Jianfeng Feng, from Fudan University and Warwick University, added: "We know that depression can start as early as in adolescence or young adulthood, so educating young people on the importance of a healthy lifestyle and its impact on mental health should begin in schools."

https://www.sciencedaily.com/releases/2023/09/230911141148.htm

'Night owls' more likely than 'early birds' to develop diabetes

September 11, 2023

Science Daily/Brigham and Women's Hospital

A new study has an important message for people who consider themselves night owls. Investigators from Brigham and Women's Hospital, a founding member of the Mass General Brigham healthcare system, found that people with later sleep and wake times had less healthy lifestyles and were at greater risk of developing diabetes than those with early-bird sleep habits.

Investigators found evening 'chronotype,' or going to bed late and waking up late, was associated with a 19 percent increased risk of diabetes after accounting for lifestyle factors

A new study has an important message for people who consider themselves night owls. Investigators from Brigham and Women's Hospital, a founding member of the Mass General Brigham healthcare system, found that people with later sleep and wake times had less healthy lifestyles and were at greater risk of developing diabetes than those with early-bird sleep habits. Their results are published in the Annals of Internal Medicine.

"Chronotype, or circadian preference, refers to a person's preferred timing of sleep and waking and is partly genetically determined so it may be difficult to change," said corresponding author Tianyi Huang, MSc, ScD, an associate epidemiologist in the Brigham's Channing Division of Network Medicine. "People who think they are 'night owls' may need to pay more attention to their lifestyle because their evening chronotype may add increased risk for type 2 diabetes."

The researchers previously found that people with more irregular sleep schedules are at higher risk of developing diabetes and cardiovascular disease and that people with evening chronotypes are more likely to have irregular sleep patterns. For this study, they wanted to understand the relationship between chronotype and diabetes risk and looked at the role of lifestyle factors as well.

The team analyzed data from 63,676 female nurses from the Nurses' Health Study II collected from 2009-2017 and included self-reported chronotype (the extent to which participants perceived themselves to be an evening person or a morning person), diet quality, weight and body mass index, sleep timing, smoking behaviors, alcohol use, physical activity, and family history of diabetes. The team determined diabetes status from the participants' self-reports and medical records.

The Nurses' Health Study II, a joint effort between the Brigham's Channing Division of Network Medicine and Harvard T.H. Chan School of Public Health, is among the largest investigations into risk factors for major chronic diseases in women. One of the study's strengths is its regular follow-up of study participants and repeated assessment of health and lifestyle factors.

Approximately 11 percent of participants reported having a 'definite evening' chronotype and about 35 percent reported having 'definite morning' chronotype. The remaining population, around half, were labeled as 'intermediate,' meaning they either identified as being neither a morning nor evening type or as being only slightly more one than the other.

The evening chronotype was associated with a 72 percent increased risk for diabetes before accounting for lifestyle factors. After accounting for lifestyle factors, evening chronotype was associated with a 19 percent increased risk of diabetes. Among those in the study with the healthiest lifestyles, only 6 percent had evening chronotypes. Among those with the unhealthiest lifestyles 25 percent were evening chronotypes.

Those with evening chronotypes were found to be more likely to drink alcohol in higher quantities, have a low-quality food diet, get less hours of sleep per night, currently smoke, and have weight, BMI, and physical activity rates in the unhealthy range.

"When we controlled for unhealthy lifestyle behaviors, the strong association between chronotype and diabetes risk was reduced but still remained, which means that lifestyle factors explain a notable proportion of this association," said first author Sina Kianersi, DVM, PhD, a postdoctoral research fellow in the Brigham's Channing Division of Network Medicine.

They also found the association between evening chronotype and diabetes risk only in those nurses who worked day shifts and not those who worked overnight shifts.

"When chronotype was not matched with work hours we saw an increase in type 2 diabetes risk," said Huang. "That was another very interesting finding suggesting that more personalized work scheduling could be beneficial."

The Nurses' Health Study is comprised mainly of white female nurses -- future investigations will be needed to determine if the patterns detected here are consistent across populations. The study's results point to associations but cannot determine causality -- it's possible that other factors may contribute to a person's chronotype, propensity for unhealthy habits and risk of diabetes.

Next, the researchers plan to investigate genetic determinants of chronotype and its association with cardiovascular disease, in addition to diabetes, in larger, more diverse populations.

"If we are able to determine a causal link between chronotype and diabetes or other diseases, physicians could better tailor prevention strategies for their patients," says Kianersi.

https://www.sciencedaily.com/releases/2023/09/230911191004.htm

Hobbies linked to lower depression levels among older people

September 11, 2023

Science Daily/University College London

A new study aimed to see if the benefits of hobbies were consistent in different national settings, and looked at data from 93,263 people aged 65 or over who had enrolled in five existing longitudinal studies in England, Japan, United States, China and 12 European countries.

Having a hobby is linked to fewer depressive symptoms and higher levels of happiness, self-reported health and life satisfaction among people aged 65 and over, and this holds true across 16 countries on three continents, according to a new study led by UCL (University College London) researchers.

The study, published in the journal Nature Medicine, aimed to see if the benefits of hobbies were consistent in different national settings, and looked at data from 93,263 people aged 65 or over who had enrolled in five existing longitudinal studies in England, Japan, United States, China and 12 European countries.

Analysing data from participants spanning four to eight years, the researchers found that having a hobby was also linked to subsequent decreases in depressive symptoms and increases in happiness and life satisfaction, suggesting there might be a causal effect, although as an observational study it could not prove causality.

These results remained after adjusting for other factors such as partnership status, employment and household income.

The study found the benefits of having a hobby were relatively universal, with only small differences between countries.

Lead author Dr Karen Mak (UCL Institute of Epidemiology & Health Care) said: "Our study shows the potential of hobbies to protect older people from age-related decline in mental health and wellbeing. This potential is consistent across many countries and cultural settings.

"Of the four outcomes, life satisfaction was most strongly linked to hobby engagement. Hobbies may contribute to life satisfaction in our later years through many mechanisms, including feeling in control of our minds and bodies, finding a purpose in life, and feeling competent in tackling daily issues.

"Theoretical work suggests the relationship between hobbies and wellbeing may cut both ways -- that people with better mental health may be more likely to take up a hobby, and persisting with a hobby may help us to retain improved life satisfaction.

"Our research also supports policymakers in promoting access to hobbies among older people as a way to enhance their wellbeing and health."

Hobbies, defined as activities people engage in during their leisure time for pleasure, might range from volunteering or being part of a club to reading, gardening, playing games, and arts and crafts.

The researchers found the proportion of people who said they had a hobby varied considerably between countries, with 51% of study participants in Spain reporting having a hobby, compared to 96% in Denmark, 95.8% in Sweden and 94.4% in Switzerland.

China had the lowest level of hobby engagement, at 37.6%, but researchers cautioned that study respondents in China were asked only about social hobbies, not hobbies in general.

In countries with better life expectancy and national happiness levels, more people reported having a hobby, and also the link between wellbeing and having a hobby was stronger in those countries.

The five longitudinal studies were: the English Longitudinal Study of Ageing (ELSA), the Japan Gerontological Evaluation Study (JAGES), US Health and Retirement Study (HRS), Survey of Health, Ageing and Retirement in Europe (SHARE), and China Health and Retirement Longitudinal Study (CHARLS). In ELSA, JAGES, and HRS, participants were asked about hobbies and the word was not defined; in SHARE and CHARLS, participants were asked if they engaged in a specific list of hobbies.

https://www.sciencedaily.com/releases/2023/09/230911141131.htm

Sleep-wake therapy gives new hope for teens with depression

September 8, 2023

Science Daily/University of California - San Francisco

School systems aren't built for kids who fall asleep and wake up late, the so-called 'night owls,' which may help explain why this group of teens is more prone to depression.

Promoting healthy sleep in teen night owls brings adolescents' biology and school demands in alignment.

Now, researchers at UC San Francisco have found a way to help these kids adjust to their natural sleep-cycle rhythms while still fulfilling their school responsibilities. The findings are a welcome sign for adolescents with depression, who are more likely than most to report staying up late.

While 40% of teens overall report being night owls, in those with depression, 80% report late-night sleep patterns.

The key to success with the current intervention was teaching the night owls to structure their lives so they could sleep as late as possible, while gently training their bodies to fall asleep a little earlier.

"A big finding here is that there is a subgroup of teens for whom treating sleep is particularly important for improving depression symptoms," said Lauren Asarnow, PhD, a clinical psychologist with UCSF Health who specializes in sleep health. "And the other big finding is that they really need to be able to live a life that is more in line with their sleep-wake biology.

It's Biology, Not Laziness

The study, published in August in the Journal of Child Psychology and Psychiatry, analyzed data from 42 participants with clinical depression who had been part of a larger study of 176 night-owl adolescents. Twenty-four of these adolescents received the intervention, called the Transdiagnostic Sleep and Circadian Intervention (TransS-C), and 18 received educational sessions on how to lead a healthy lifestyle. All participants kept sleep diaries and wore devices that measured the quality of their sleep. They also received 45-minute therapy sessions each week for eight weeks.

At the beginning of the study, all of the teens scored at least 40 on the Children's Depression Rating Scale, a level that indicates clinically significant depression. A score of 28 or lower indicates remission. Six months after the treatment, the intervention group's average score had fallen to 21.67, compared to 32.5 for the group that received the healthy lifestyle intervention. At 12 months post-treatment, the intervention scored 24.97, while controls were at 32.75.

A larger study has since been funded by the National Institute of Mental Health, and it will be open for enrollment to 200 teens in the Bay Area this fall.

About 3 million adolescents have at least one major depressive episode in a given year, and about 40% don't respond to treatment. Teens whose natural tendencies are to fall asleep later and wake up later are at higher risk for recurrent depression, more severe depression, suicidality and poor antidepressant response, research shows.

"There is a saying in our psychology and psychiatry clinics that the best treatment for depression and anxiety is summer break," Asarnow said. "We need to stop calling these kids 'lazy.' A lot of the time it is just their biology. It's not their fault."

https://www.sciencedaily.com/releases/2023/09/230908161055.htm

High blood pressure while lying down linked to higher risk of heart health complications

September 7, 2023

Science Daily/American Heart Association

People who had high blood pressure while lying flat on their backs had a higher risk of heart attack, stroke, heart failure or premature death, according to new research to be presented at the American Heart Association's Hypertension Scientific Sessions 2023, to be held Sept. 7-10, 2023, in Boston. The meeting is the premier scientific exchange focused on recent advances in basic and clinical research on high blood pressure and its relationship to cardiac and kidney disease, stroke, obesity and genetics.

The autonomic nervous system regulates blood pressure in different body positions; however, gravity may cause blood to pool when seated or upright, and the body is sometimes unable to properly regulate blood pressure during lying, seated and standing positions, the authors noted.

"If blood pressure is only measured while people are seated upright, cardiovascular disease risk may be missed if not measured also while they are lying supine on their backs," said lead study author Duc M. Giao, a researcher and a 4th-year M.D. student at Harvard Medical School in Boston.

To examine body position, blood pressure and heart health risk, the researchers examined health data for 11,369 adults from the longitudinal Atherosclerosis Risk in Communities (ARIC) study. The data on supine and seated blood pressure was gathered during the enrollment period, ARIC visit 1, which took place between 1987-1989. Participants had their blood pressure taken while briefly lying down at a clinic. The average age of participants at that time was 54 years old; 56% of the group self-identified as female; and 25% of participants self-identified as Black race. Participants in this analysis were followed for an average of 25 to 28 years, up through ARIC visit 5, which includes health data collected from 2011-2013.

The researcher's findings included:

• 16% percent of participants who did not have high blood pressure -- defined in this study as having top and bottom blood pressure measures greater than or equal to 130/80 mm Hg -- while seated had high blood pressure while lying supine (flat on their backs), compared to 74% of those with seated high blood pressure who also had supine high blood pressure.

• In comparison to participants who did not have high blood pressure while seated and supine, participants who had high blood pressure while seated and supine had a 1.6 times higher risk of developing coronary heart disease; a 1.83 times higher risk of developing heart failure; a 1.86 times higher risk of stroke; a 1.43 times higher risk of overall premature death; and a 2.18 times higher risk of dying from coronary heart disease

• Participants who had high blood pressure while supine but not while seated had similar elevated risks as participants who had high blood pressure while both seated and supine.

• Differences in blood pressure medication use did not affect these elevated risks in either group.

"Our findings suggest people with known risk factors for heart disease and stroke may benefit from having their blood pressure checked while lying flat on their backs," Giao said.

"Efforts to manage blood pressure during daily life may help lower blood pressure while sleeping. Future research should compare supine blood pressure measurements in the clinic with overnight measurements."

The study's limitations included that it focused on adults who were middle-aged at the time of enrollment, meaning the results might not be as generalizable to older populations, Giao said.

https://www.sciencedaily.com/releases/2023/09/230907130421.htm

Antidepressant use in people with both physical health problems and depression

Systematic Review performed at Charité and Aarhus University investigates efficacy and safety

September 7, 2023

Science Daily/Charité - Universitätsmedizin Berlin

Many people with diseases such as cancer or diabetes or those who have had a heart attack or stroke also suffer from depression. How effective are antidepressants for these patients? And are they just as safe for these people as for those without physical health problems? Researchers from Charité -- Universitätsmedizin Berlin and Aarhus University in Denmark have teamed up to investigate these questions. They compiled and analyzed studies published over several decades from around the world in a systematic review. Their findings are highly relevant to clinical practice. They have now been published in the journal JAMA Psychiatry.

"About 20 percent of people with physical health problems also suffer from depression, and both should be treated," says Prof. Christian Otte, Director of the Department of Psychiatry and Neurosciences on the Charité Campus Benjamin Franklin. "Contraindications and interactions with other medications that the patient is taking are important factors in choosing the right antidepressant. Luckily, though, there are many different antidepressants with different mechanisms of action these days, so there is at least one suitable medication to treat depression that is an option for people with almost any physical issue," Otte explains. Even so, one question has thus far remained open for both patients and their doctors: Are antidepressants in fact effective and safe in these individual cases? "We didn't have a conclusive answer to that until now," Otte says. "After all, the studies that go toward approving antidepressants are performed almost exclusively in physically healthy subjects."

In-depth review of the existing research

To summarize the existing research from around the world, the team working on the study systematically searched several medical databases, looking at meta-analyses of clinical trials. The researchers applied strict selection criteria: "In our work, we only considered analyses that synthesize data from randomized controlled studies, since they are the best way to investigate a medication's efficacy and safety," says Dr. Ole Köhler-Forsberg, a depression researcher at Aarhus University. "Overall, we identified 52 high-quality meta-analyses for 27 different physical health problems, especially cancer, heart and metabolic diseases, as well as rheumatological and neurological disorders." Otte explains: "We were able to show that antidepressants are in fact about equally effective and safe in patients with both depression and physical health problems as in those without these physical health conditions." Antidepressants do cause a somewhat higher incidence of side effects than placebo treatment, but the researchers do not believe there are any general safety concerns about using these treatments for people with physical health issues.

Findings with high clinical relevance

"These findings are good news for people with depression and physical health problems -- and they are highly relevant to clinical practice," Otte explains. "Quality of life is often severely impaired, especially by depression. We also know that the course of physical disease is worse in patients who also have depression, so treating those patients with antidepressants in addition to other therapeutic measures can really help." The researchers expect the study results to be included in the Nationale VersorgungsLeitlinie (NVL), the German national disease management guidelines, for depression. These guidelines are a joint initiative by the German Medical Association (Bundesärztekammer), the National Association of Statutory Health Insurance Physicians (Kassenärztliche Bundesvereinigung), and the German Association of the Scientific Medical Societies (AWMF) aimed at improving the quality of medical treatment in the country.

"We were surprised to see how few large-scale studies there are on this topic at all, especially in frequent combinations such as cancer with depression. We believe there is still a lot of research to be done in this area," Otte says. He and his team are already planning future projects to find out whether antidepressants might have other effects beyond improving depression and whether they could also alleviate individual symptoms of other physical health problems that are present at the same time, for example.

https://www.sciencedaily.com/releases/2023/09/230907105822.htm

Concussions early in life tied to late life cognitive decline

September 6, 2023

Science Daily/American Academy of Neurology

A study of twins shows that having a concussion early in life is tied to having lower scores on tests of thinking and memory skills decades later as well as having more rapid decline in those scores than twins who did not have a concussion, or traumatic brain injury (TBI). The study is published in the September 6, 2023, online issue of Neurology®, the medical journal of the American Academy of Neurology.

"These findings indicate that even people with traumatic brain injuries in earlier life who appear to have fully recovered from them may still be at increased risk of cognitive problems and dementia later in life," said study author Marianne Chanti-Ketterl, PhD, MSPH, of Duke University in Durham, North Carolina. "Among identical twins, who share the same genes and many of the same exposures early in life, we found that the twin who had a concussion had lower test scores and faster decline than their twin who had never had a concussion."

The study involved 8,662 men who were World War II veterans. The participants took a test of thinking skills at the start of the study when they were an average age of 67 and then again up to three more times over 12 years. Scores for the test can range from zero to 50. The average score for all participants at the beginning of the study was 32.5 points.

A total of 25% of the participants had experienced a concussion in their life.

Twins who had experienced a concussion were more likely to have lower test scores at age 70, especially if they had a concussion where they lost consciousness or were older than 24 when they had their concussion. Those twins with traumatic brain injury with loss of consciousness, more than one traumatic brain injury and who had their injuries after age 24 were more likely to have faster cognitive decline than those with no history of traumatic brain injury.

For example, a twin who experienced a traumatic brain injury after age 24 scored 0.59 points lower at age 70 than his twin with no traumatic brain injury, and his thinking skills declined faster, by 0.05 points per year.

These results took into account other factors that could affect thinking skills, such as high blood pressure, alcohol use, smoking status and education.

"Although these effect sizes are modest, the contribution of TBI on late life cognition, in addition to numerous other factors with a detrimental effect on cognition, may be enough to trigger an evaluation for cognitive impairment," Chanti-Ketterl said. "With the trend we are seeing with increased emergency room visits due to sports or recreation activity injuries, combined with the estimated half million members of the military who suffered a TBI between 2000 and 2020, the potential long-term impact of TBI cannot be overlooked. These results may help us identify people who may benefit from early interventions that may slow cognitive decline or potentially delay or prevent dementia."

A limitation of the study was that traumatic brain injuries were reported by the participants, so not all injuries may have been remembered or reported accurately.

https://www.sciencedaily.com/releases/2023/09/230906161815.htm

How sleep deprivation can harm the brain

September 6, 2023

Science Daily/American Chemical Society

Not only does a lack of sleep make you feel awful, research has shown it impairs the brain. What's more, sleep loss over long periods can even increase risk for Alzheimer's and other neurological diseases. Researchers want to understand how sleep deprivation causes this harm. In a new study in ACS' Journal of Proteome Research, a team working with mice has identified a protective protein whose level declines with sleep deprivation, leading to neuronal death.

Studies indicate that lack of sleep leads to neurological damage in the hippocampus, a part of the brain involved in learning and memory. To better understand the changes responsible for this effect, scientists have begun examining shifts in the abundance of proteins and RNA, which contains genetically encoded instructions derived from DNA. In this way, previous studies have identified some factors linking sleep loss to damage; however, researchers haven't generally confirmed they play a role in cognitive function within larger animal populations. So, Fuyi Xu, Jia Mi and their colleagues set out to further explore how sleep loss damages the brain and to corroborate their findings.

To start off, the researchers evaluated how well mice navigated a simple maze and learned to recognize new objects after having been sleep deprived for two days. They then extracted the proteins in the animals' hippocampi and identified those whose abundance changed. Then, to further narrow the possibilities, they looked at data linking these proteins to maze performance in related strains of mice that had not experienced sleep deprivation.

This approach led the researchers to pleiotrophin (PTN), which declined in the sleep-deprived mice. Through an analysis of RNA, the team identified the molecular pathway by which a loss of PTN causes cells in the hippocampus to die. When they looked at genetic studies in humans, they found that PTN is implicated in Alzheimer's and other neurodegenerative diseases. This research has uncovered a new mechanism by which sleep protects brain function, according to the researchers, who also note that PTN levels could serve as an indicator of cognitive impairment resulting from insomnia.

https://www.sciencedaily.com/releases/2023/09/230906143429.htm

Positive body image linked to better life satisfaction

Largest study of its kind also finds people in rural areas appreciate their bodies more

September 5, 2023

Science Daily/Anglia Ruskin University

A major international study, involving 56,968 participants in 65 nations, has found that positive body image is strongly associated with better psychological wellbeing and life satisfaction. It also found that body appreciation is higher in those who are single and those living in rural areas. Amongst the 65 nations, Australia followed by India and then the United Kingdom recorded the lowest scores, while Malta scored highest.

Having more positive body image is strongly associated with better psychological wellbeing and life satisfaction, according to a new study led by Anglia Ruskin University (ARU) in England.

Published in the journal Body Image, the research is one of the largest studies ever conducted on the topic of body image, involving 56,968 participants in 65 nations.

The research was focused on 'body appreciation', defined as "accepting, holding favourable opinions toward, and respecting the body, while also rejecting media-promoted appearance ideals as the only form of human beauty."

Previous research has shown that high levels of body appreciation are linked to a range of positive wellbeing traits such as improved self-esteem and healthy eating habits, and negatively associated with issues such as depression and anxiety. However, few studies have assessed body appreciation across nations.

Led by researchers from Anglia Ruskin University (ARU), a consortium of scientists asked participants in 65 nations to complete the Body Appreciation Scale-2 (BAS-2), which contains 10 items, including 'I respect my body' and 'I appreciate the different and unique characteristics of my body'.

The study found that across nations, greater body appreciation was significantly associated with higher psychological wellbeing, as assessed using a measure of life satisfaction. The researchers also found that body appreciation was higher in participants who were single (compared with being married or in a committed relationship) and those living in rural areas.

The study also found large differences in body appreciation scores across the 65 survey nations. The lowest scores were recorded by Australia, followed by India and then the United Kingdom. At the other end of the scale, Malta scored highest.

Viren Swami, Professor of Social Psychology at Anglia Ruskin University (ARU) and lead author of the study, said: "This is one of the largest studies on body image ever carried out, brought about by a collaborative research effort involving over 250 scientists across the world. Our finding that greater body appreciation is associated with better psychological wellbeing highlights the importance of developing ways to promote more positive body image globally.

"Also, people who live in urban areas may feel stronger pressure to conform to body ideals promoted by Western society, and it is also notable that people from countries considered culturally different to the United States appeared to have broadly greater body appreciation. People in rural areas may also benefit from being in nature, which past research has also shown to be linked with positive body image.

https://www.sciencedaily.com/releases/2023/09/230905155551.htm

Active children are more resilient

September 5, 2023

Science Daily/University of Basel

The school year has hardly begun and the first exams are already approaching. According to findings by researchers from the University of Basel, school children cope better with the stress if they get plenty of daily exercise.

"Get some exercise!" It's one suggestion adults frequently hear when they complain about stress in their lives. Exercise helps relieve stress. But does this also apply to children? Does exercise help them manage the pressures to achieve at school? A research team led by Dr. Manuel Hanke and Dr. Sebastian Ludyga from the Department of Sport, Exercise and Health recently examined the effect of physical activity on children's stress levels. Their findings appear in the Journal of Science and Medicine in Sport.

For their study, they had 110 children between the ages of 10 and 13 wear a sensor tracking their daily movement over the course of a week. They then brought the participants into the lab on two separate occasions to complete a stressful task and a non-stressful control task (see the box). The researchers tested the children's physical stress reaction via the concentration of the stress hormone cortisol in their saliva.

Less cortisol in active children

"We wanted to determine whether physical activity makes children more resilient under laboratory-controlled circumstances," explains project director Sebastian Ludyga. The results showed that the participants who got more than an hour of exercise per day, as the World Health Organization (WHO) recommends, did in fact produce less cortisol in the stress task than the children who were less active.

"Regularly active children seem to have a reduced physiological stress reaction in general," notes Manuel Hanke, lead author of the study. Even in the control task, which involved an unfamiliar situation, making it still somewhat unsettling for the participants, there was a difference in cortisol levels between more and less active children -- though overall cortisol levels were lower than in the stress task.

Stress hormone levels increase during exercise

One possible explanation for this finding could be that cortisol levels also increase during exercise, says Sebastian Ludyga. "When children regularly run, swim, climb, etc., the brain learns to associate a rise in cortisol with something positive. The body's reaction always has a cognitive component as well: this positive association helps to prevent the concentration of cortisol from rising to too high a level in exam situations as well."

Besides their analysis of the saliva samples, the researchers also examined cognitive reactions to the stress task by recording participants' brainwaves via electroencephalogram (EEG). The team plans to analyze these data next. "Stress can interfere with thinking. Some of us are familiar with this in its most extreme form -- a blackout," Hanke explains. The team now aims to determine whether physical activity also has an influence on these cognitive effects of stress.

Methodology

For their study, the researchers used the Trier Social Stress Test for Children: the participants had to read a story with an open ending, then had five minutes to prepare before using their notes to tell the rest of the story for a jury. What they didn't know in advance was that the preparation time was intentionally kept so short so that it would not be sufficient. After about a minute, their notes were mostly exhausted but they still had to fill five minutes and think something up on the spur of the moment. This task was followed by a seemingly simple arithmetic task in which participants were asked to repeatedly reduce a number in the high three digits by a certain value over the course of five minutes. The stress in this task is primarily caused by errors, which require the participant to restart the task from the beginning. In the control task, which was conducted on a separate occasion, the children also had to read a story, but they then discussed general questions about the story with a researcher without any pressure to perform. In both sessions, the researchers took saliva samples at regular intervals before and after the tasks in order to measure cortisol levels.

https://www.sciencedaily.com/releases/2023/09/230905124926.htm

Study confirms it: Opposites don't actually attract

A sweeping new analysis including data from millions of couples shows that birds of a feather flock together

September 5, 2023

Science Daily/University of Colorado at Boulder

A new study looked at more than 130 traits and involved millions of couples over more than a century. It found little evidence that opposites attract. Instead, for 82% to 89% of traits, partners tended to be similar.

Opposites don't actually attract.

That's the takeaway from a sweeping CU Boulder analysis of more than 130 traits and including millions of couples over more than a century.

"Our findings demonstrate that birds of a feather are indeed more likely to flock together," said first author Tanya Horwitz, a doctoral candidate in the Department of Psychology and Neuroscience and the Institute for Behavioral Genetics (IBG).

The study, published Aug. 31 in the journal Nature Human Behaviour, confirms what individual studies have hinted at for decades, defying the age-old adage that "opposites attract."

It found that for between 82% and 89% of traits analyzed -- ranging from political leanings to age of first intercourse to substance use habits -- partners were more likely than not to be similar.

For only 3% of traits, and only in one part of their analysis, did individuals tend to partner with those who were different than them.

Aside from shedding light on unseen forces that may shape human relationships, the research has important implications for the field of genetic research.

"A lot of models in genetics assume that human mating is random. This study shows this assumption is probably wrong," said senior author and IBG Director Matt Keller, noting that what is known as "assortative mating" -- when individuals with similar traits couple up -- can skew findings of genetic studies.

Looking back more than a century

For the new paper, the authors conducted both a review, or meta-analysis, of previous research and their own original data analysis.

For the meta-analysis, they looked at 22 traits across 199 studies including millions of male-female co-parents, engaged pairs, married pairs or cohabitating pairs. The oldest study was conducted in 1903.

In addition, they used a dataset called the UK Biobank to study 133 traits, including many that are seldom studied, across almost 80,000 opposite-sex pairs in the United Kingdom.

Same sex couples were not included in the research. Because the patterns there may differ significantly, the authors are now exploring those separately.

Across both analyses, traits like political and religious attitudes, level of education, and certain measures of IQ showed particularly high correlations. For instance, on a scale in which zero means there is no correlation and 1 means couples always share the trait, the correlation for political values was .58.

Traits around substance use also showed high correlations, with heavy smokers, heavy drinkers and teetotalers tending strongly to partner up with those with similar habits.

Meanwhile, traits like height and weight, medical conditions and personality traits showed far lower but still positive correlations. For instance, the correlation for neurotocism was .11.

For some traits, like extroversion, there was not much of a correlation at all.

"People have all these theories that extroverts like introverts or extroverts like other extroverts, but the fact of the matter is that it's about like flipping a coin: Extroverts are similarly likely to end up with extroverts as with introverts," said Horwitz.

Rarely, opposites may attract

In the meta-analysis, the researchers found "no compelling evidence" on any trait that opposites attract. In the UK Biobank sample, they did find a handful of traits in which there seemed to be a negative correlation, albeit small.

Those included: chronotype (whether someone is a "morning lark" or "night owl"), tendency to worry and hearing difficulty.

More research must be done to unpack those findings, they said.

The trait for which couples were most likely to be similar was, not surprisingly, birth year.

But even seldom-studied traits, like how many sexual partners a person had had or whether they had been breastfed as a child, showed some correlation.

"These findings suggest that even in situations where we feel like we have a choice about our relationships, there may be mechanisms happening behind the scenes of which we aren't fully aware," said Horwitz.

Next-generation implications

The authors note that couples share traits for a variety of reasons: Some grow up in the same area. Some are attracted to people who are similar to them. Some grow more similar the longer they are together.

Depending on the cause, there could be downstream consequences.

For example, Horwitz explains, if short people are more likely to produce offspring with short people and tall people with tall people, there could be more people at the height extremes in the next generation. The same goes for psychiatric, medical or other traits.

There could also be social implications.

For instance, some small previous studies have suggested that people in the U.S. are growing more likely to couple up with people with similar educational backgrounds -- a trend that, some theorize, could widen the socioeconomic divide.

Notably, the new study also showed that the strength of correlations for traits differed across populations. They likely also change over time, the authors suspect.

The researchers caution that the correlations they found were fairly modest and should not be overstated or misused to promote an agenda (Horwitz points out that assortative mating research was, tragically, co-opted by the eugenics movement).

They do hope the study will spark more research across disciplines, from economics to sociology to anthropology and psychology.

"We're hoping people can use this data to do their own analyses and learn more about how and why people end up in the relationships they do," she said.

https://www.sciencedaily.com/releases/2023/09/230905124922.htm

Synchronizing your internal clocks may help mitigate jet lag, effects of aging

A hearty breakfast instead of a midnight snack could lead to better sleep when traveling

September 5, 2023

Science Daily/American Institute of Physics

Traveling to faraway places is a great way to seek out new experiences, but jet lag can be an unpleasant side effect. Adjusting to a new time zone is often accompanied by fatigue, difficulty sleeping, and a host of other problems that can turn an otherwise exciting adventure into a miserable trip.

Jet lag is caused by a difference between the circadian system -- the body's internal clock -- and the surrounding environment. Around the turn of the century, scientists began to recognize that the body has multiple internal clocks, calibrated in different ways, and that jet lag-like symptoms can result when these clocks drift out of sync with each other. This can happen in several ways and grows more prevalent with age.

In Chaos, from AIP Publishing, a team of scientists from Northwestern University and the Santa Fe Institute developed a theoretical model to study the interactions between multiple internal clocks under the effects of aging and disruptions like jet lag.

Modern research has shown that circadian clocks are present in almost every cell and tissue in the body. Each relies on its own set of cues to calibrate; the brain's clock depends on sunlight, for instance, while the peripheral organs calibrate at mealtime.

"Conflicting signals, such as warm weather during a short photoperiod or nighttime eating -- eating when your brain is about to rest -- can confuse internal clocks and cause desynchrony," said author Yitong Huang.

At this point, little is known about how the body's various internal clocks affect each other. The added complexity of accounting for multiple clocks means researchers tend to use simplified models.

"Most studies primarily focus on one particular time cue or a single clock," said Huang. "Important gaps remain in our understanding of the synchronization of multiple clocks under conflicting time cues."

Huang and her colleagues took a different approach, building a mathematical framework that accounts for this complex interplay between systems. Their model features two populations of coupled oscillators that mimic the natural rhythms of circadian cycles. Each oscillator influences the others while simultaneously adjusting based on unique external cues.

Using this model, the team was able to explore how such a coupled system could be disrupted and what makes the effect worse. They found that common symptoms of aging, such as weaker signals between circadian clocks and a lower sensitivity to light, result in a system that is more vulnerable to disruptions and slower to recover.

They also landed on a new method to speed up recovery from jet lag and similar disruptions. According to their results, the way to better sleep is through the stomach.

"Having a larger meal in the early morning of the new time zone can help overcome jet lag," says Huang. "Constantly shifting meal schedules or having a meal at night is discouraged, as it can lead to misalignment between internal clocks."

The authors plan to investigate the other side of the equation and identify the factors that result in more resilient internal clocks. Such discoveries could result in recommendations to prevent jet lag in the first place, or to keep the circadian system healthy into old age.

https://www.sciencedaily.com/releases/2023/09/230905124904.htm

Toddlers learn to reason logically before they learn to speak

September 5, 2023

Science Daily/Universitat Pompeu Fabra - Barcelona

Nineteen-month-old toddlers already use natural logical thinking, even before they learn to speak, to deal with uncertainties about the world. This natural logic contributes to their learning process, both in terms of language and in other fields of knowledge, according to a new study.

How do we learn to speak during childhood or how do we acquire knowledge about the world around us? Toddlers' social interactions in their social and family environment and in schools help to explain this, but they are not the only factors involved. Natural logical thinking, which manifests itself from a very early age and does not depend on knowledge of language, also facilitates the learning process, according to a study led by UPF's Center for Brain and Cognition, the results of which have been published this Friday, 1 September, in the journal Current Biology.

The study focuses on a question that still generates debate among neuroscientists: whether infants who have not yet learned to speak (or are developing speech) are capable of logical reasoning. This pioneering research shows that this natural logical reasoning exists from at least 19 months of age, does not depend on knowledge of language and is developed mainly through the strategy of exclusion by elimination. In other words, if toddlers are faced with an unknown reality, they would try to analyse it and reach some conclusion about it by ruling out the options that are not possible, according to their level of knowledge at the time.

The results of the paper are presented in the article entitled The scope and role of deduction in infant cognition, written by Kinga Anna Bohus, Nicolo Cesana-Arlotti, Ana Martín-Salguero and Luca Lorenzo Bonatti. The principal researcher, L. Bonatti (ICREA), is the director of the Reasoning and Infant Cognition (RICO) research group at the Center for Brain and Cognition (CBC) at UPF. Kinga Anna Bohus (main author) also belongs to the group. N. Cesana-Arlotti and Ana Martín-Salguero, previously linked to the CBC at UPF, are currently researchers at Yale University (USA) and at the École Normale Supérieure in Paris.

Toddlers tend to solve uncertainties by ruling out impossible options according to the level of knowledge they have at any given moment

The study analyses the importance of two strategies for infants to deal with uncertainties: association and exclusion (or disjunction elimination). The first strategy would mean that toddlers hearing a new word that may refer to two unfamiliar objects that they can see, mentally associate the term with each of them. Subsequently, they would associate the term with the object with which this name fits better.

The second strategy (exclusion) explains how a toddler can learn a new word through logical reasoning by eliminating alternatives. For example, if they see two objects (A and B) and hear an unknown term that they know is not A (because they know the name of A), they will determine that it is the name of B. This is the predominant strategy, according to the results of the study.

Two experiments to analyse toddlers' natural logic posed with known and unknown objects and terms

The research team conducted two different experiments, the first with 61 monolingual (26) and bilingual (35) 19-month-old toddlers and the second with 33 (19 mono and 14 bilingual). The analysis of each group was crucial to determine whether deductive processes depend on linguistic experience.

In the first experiment, the participants were shown two objects, which they had to associate with one of the words they heard, through different tests. In the first test, they had to look at two objects they knew (e.g., a spoon and a biscuit) and, upon hearing a term (e.g., spoon), associate it with one of the two. In the second test, the infants were shown an object they knew (e.g., an apple) and an object they did not know (e.g., a carburettor), and they heard the word corresponding to the known object (apple), which they had to identify. The third test was the same as the second, except that the word heard corresponded to the unknown word (e.g., carburettor).

In the second experiment, two objects or animate beings were used (for example, an umbrella and a figure of a boy), each associated with a sound. Subsequently, the two objects were covered so that the infant could not see them and one of them was placed in a glass. When they were uncovered, the toddler could only see one of the two objects and had to guess, by elimination, which one was inside the glass. In a subsequent test (with the two objects covered and without changing their position), the infant listened to the sound associated with one of them and it was analysed whether he/she looked in the direction of the correct object.

In all these tests, their gaze movement patterns were assessed. For example, when reasoning by exclusion, toddlers look at object A and, if they rule out that the term they have heard refers to it, then they turn their gaze towards B. This is known as the double check strategy.

There are no relevant differences in the logic of monolingual and bilingual toddlers

The main author of the research, Kinga Anna Bohus, summarizes the main findings of the study as follows: "We studied the presence of the concept of logical disjunction in 19-month-old infants. In a word-referent mapping task, both bilingual and monolingual infants display a pattern of oculomotor inspection previously found to be a hallmark of disjunctive reasoning in adults and children."

In short, the results of the study show no relevant differences between the logical reasoning of monolingual and bilingual toddlers, which confirms that it does not depend on linguistic knowledge. This natural logical thinking could be present before the age of 19 months, although there is still not enough scientific evidence to demonstrate its presence at earlier ages.

https://www.sciencedaily.com/releases/2023/09/230905125028.htm

Adding complex component of milk to infant formula confers long-term cognitive benefits for bottle-fed babies

August 31, 2023

Science Daily/University of Kansas

New research has shown how a complex component of milk that can be added to infant formula has been shown to confer long-term cognitive benefits, including measures of intelligence and executive function in children.

Breast milk is widely acknowledged as the most beneficial nutrition for infants, but many families face medical or logistical challenges in breastfeeding. In the U.S., just 45% of infants continue to be exclusively breastfed at 3 months of age, according to the Centers for Disease Control.

For decades, researchers have sought to create a viable complement or alternative to breast milk to give children their best start for healthy development. New research out of the University of Kansas has shown how a complex component of milk that can be added to infant formula has been shown to confer long-term cognitive benefits, including measures of intelligence and executive function in children.

The research by John Colombo, KU Life Span Institute director and investigator, along with colleagues at Mead Johnson Nutrition and in Shanghai, China, adds to the growing scientific support for the importance of ingredients found in milk fat globule membrane (MFGM) in early human development.

The study, which was published in the Journal of Pediatrics, showed that feeding infants formula supplemented with MFGM and lactoferrin for 12 months raised IQ by 5 points at 5 ½ years of age. The effects were most evident in tests of children's speed of processing information and visual-spatial skills. Significant differences were also seen in children's performance on tests of executive function, which are complex skills involving rule learning and inhibition.

All forms of mammalian milk contain large fat globules that are surrounded by a membrane composed of a variety of nutrients important to human nutrition and brain development, Colombo said. When milk-based infant formula is manufactured, the membrane has typically been removed during processing.

"No one thought much about this membrane," Colombo said, "until chemical analyses showed that it's remarkably complex and full of components that potentially contribute to health and brain development."

The 2023 study was a follow-up to one that Colombo also co-wrote with colleagues in Shanghai, China, published in the Journal of Pediatrics in 2019. That study showed that babies who were fed formula with added bovine MFGM and lactoferrin had higher scores on neurodevelopmental tests during the first year and on some aspects of language at 18 months of age.

The global nutrition research community has been looking at MFGM for about a decade, Colombo said. Because the membrane is made up of several different components, it isn't known whether one of the components is responsible for these benefits, or whether the entire package of nutrients act together to improve brain and behavioral development.

These benefits were seen in children long after the end of formula feeding at 12 months of age.

"This is consistent with the idea that early exposure to these nutritional components contribute to the long-term structure and function of the brain," said Colombo, who has spent much of his career researching the importance of early experience in shaping later development.

https://www.sciencedaily.com/releases/2023/08/230831142823.htm

A new breakthrough in obesity research may allow you to lose fat while eating all you want

Researchers discover that astrocytes control a cluster of neurons in the brain that regulates energy expenditure

August 31, 2023

Science Daily/Institute for Basic Science

This is a significant development that brings hope to the one billion individuals with obesity worldwide. Researchers led by Director C. Justin LEE from the Center for Cognition and Sociality (CCS) within the Institute for Basic Science (IBS) have discovered new insights into the regulation of fat metabolism. The focus of their study lies within the star-shaped non-neuronal cells in the brain, known as 'astrocytes'. Furthermore, the group announced successful animal experiments using the newly developed drug 'KDS2010', which allowed the mice to successfully achieve weight loss without resorting to dietary restrictions.

The complex balance between food intake and energy expenditure is overseen by the hypothalamus in the brain. While it has been known that the neurons in the lateral hypothalamus are connected to fat tissue and are involved in fat metabolism, their exact role in fat metabolism regulation has remained a mystery. The researchers discovered a cluster of neurons in the hypothalamus that specifically express the receptor for the inhibitory neurotransmitter 'GABA (Gamma-Aminobutyric Acid)'. This cluster has been found to be associated with the α5 subunit of the GABAA receptor and was hence named the GABRA5 cluster.

In a diet-induced obese mouse model, the researchers observed significant slowing in the pacemaker firing of the GABRA5 neurons. Researchers continued with the study by attempting to inhibit the activity of these GABRA5 neurons using chemogenetic methods. This in turn caused a reduction in heat production (energy consumption) in the brown fat tissue, leading to fat accumulation and weight gain. On the other hand, when the GABRA5 neurons in the hypothalamus were activated, the mice were able to achieve a successful weight reduction. This suggests that the GABRA5 neurons may act as a switch for weight regulation.

In a new surprising and unexpected turn of events, the research team discovered that the astrocytes in the lateral hypothalamus regulate the activity of the GABRA5 neurons. The numbers and sizes of the reactive astrocytes are increased, and they begin to overexpress the MAO-B enzyme (Monoamine Oxidase B). This enzyme plays a crucial role in the metabolism of neurotransmitters in the nervous system and is more predominantly expressed in reactive astrocytes. This ends up in the production of a large amount of tonic GABA (Gamma-Aminobutyric Acid), which inhibits the surrounding GABRA5 neurons.

It was also discovered that suppressing the expression of the MAO-B gene in reactive astrocytes can decrease GABA secretion, thereby reversing the undesirable inhibition of the GABRA5 neurons. Using this approach the researchers were able to increase the heat production in the fat tissue of the obese mice, which allowed them to achieve weight loss even while consuming a high-calorie diet. This experimentally proves that the MAO-B enzyme in reactive astrocytes can be an effective target for obesity treatment without compromising appetite.

Furthermore, a selective and reversible MAO-B inhibitor, 'KDS2010', which was transferred to a biotech company Neurobiogen in 2019 and is currently undergoing Phase 1 clinical trials, was tested on an obese mouse model. The new drugs yielded remarkable results, demonstrating a substantial reduction in fat accumulation and weight without any impacts on the amount of food intake.

Postdoctoral researcher SA Moonsun said, "Previous obesity treatments targeting the hypothalamus mainly focused on neuronal mechanisms related to appetite regulation." She added, "To overcome this, we focused on the non-neuronal 'astrocytes' and identified that reactive astrocytes are the cause of obesity."

Center Director C. Justin LEE also said, "Given that obesity has been designated by the World Health Organization (WHO) as the '21st-century emerging infectious disease,' we look to KDS2010 as a potential next-generation obesity treatment that can effectively combat obesity without suppressing appetite."

https://www.sciencedaily.com/releases/2023/08/230831121624.htm

Kindergarten conduct problems could cost society later

August 30, 2023

Science Daily/Penn State

A new economic analysis has linked, for the first time, conduct problems among kindergarten students with significant costs to society in terms of crime and associated medical expenses and lost productivity when they are adults.

"Providing effective, evidence-based programming designed to address behavioral problems early on has the potential to improve students' wellbeing in the long term," said project collaborator Damon Jones, associate research professor in the Edna Bennett Pierce Prevention Research Center (PRC). "This study implies that there could be an additional benefit of reduced need for government services and lower costs related to crime, where conduct problems are reduced."

Researchers reviewed teacher- and parent-reported data on conduct problems among more than 1,300 kindergarten students from two multi-site, longitudinal studies conducted in U.S. schools in the late 1980s and early 1990s. They used government and administrative data to determine the costs associated with crimes committed by the students through age 28. The team reported their results in the Journal of Child Psychology and Psychiatry.

The researchers found that increased behavioral problems -- such as oppositional or antisocial behavior -- in kindergarten students were linked to more than $144,000 in costs, on average, per student related to crime and associated medical expenses and lost productivity as these children reached adolescence and adulthood.

"This study is the first to establish a connection between kindergarten students' behavior and crime-related costs when the children became adults," said Yoon Hur, assistant research professor at Penn State's Evidence-to-Impact Collaborative. Hur collaborated with Natalie Goulter, lecturer at Newcastle University, on statistical analyses for the study.

Approximately 42% of the students with increased behavioral problems had costs related to crimes involving violence, substance use, public order or property. Further, 45% had costs related to government services use, 41% had costs related to medical services use and 58% had costs related to any of these categories.

"Data from studies such as these can be used by local, state and national governments to inform budget planning that could support prevention where early risk for conduct problems can be determined," Jones said. "Many studies have demonstrated that investing in young children through effective intervention can lead to economic benefits for people and public services over time."

Other collaborators on this study included Jennifer Godwin, research scientist, Duke University; Bob McMahon, investigator, BC Children's Hospital; Kenneth Dodge, the William McDougall Distinguished Professor of Public Policy Studies, Duke University; Jennifer Lansford, the S. Malcom Gills Distinguished Research Professor of Public Policy, Duke University; John Lochman, the Saxon Professor Emeritus, University of Alabama; John Bates, professor, psychological and brain sciences, Indiana University; Gregory S. Pettit, human sciences professor emeritus, Auburn University; and Max Crowley, professor of human development and family studies and public policy and director of the Evidence-to-Impact Collaborative and the PRC, Penn State.

The National Institute of Mental Health, National Institute on Drug Abuse, National Institute of Child Health and Human Development, U.S. Department of Education, BC Children's Hospital Research Institute Investigator Grant and Canada Foundation for Innovation Award funded this research.

https://www.sciencedaily.com/releases/2023/08/230830195937.htm

First-time fathers seem to experience a steeper decline in relationship satisfaction in the first two years post-partum than second-time fathers

By 14 months postpartum, second-time fathers' reported relationship satisfaction had increased back to baseline

August 30, 2023

Science Daily/PLOS

First-time fathers seem to experience a steeper decline in relationship satisfaction in the first two years post-partum than second-time fathers, who appear to recover lost relationship satisfaction by the time their second child is 14 months old, according to a study published August 30, 2023 in the open-access journal PLOS ONE by Judith T. Mack and Lena Brunke from Technische Universität Dresden, Germany, and colleagues.

Having a strong primary relationship can help couples more successfully weather potentially-challenging transitions like the birth of a child. Most research on postpartum relationship satisfaction has focused on mothers after the birth of their first child; in this study the authors studied fathers' experiences of relationship satisfaction before and after the birth of a first or second child. They also assessed how variables like age, education, income, relationship duration, marital status, child's biological sex, or child's temperament might predict relationship satisfaction for fathers over this period.

The authors analyzed survey data from 500 first-time fathers and 106 fathers expecting their second child, collected over 2017-2020 as part of the ongoing, prospective, longitudinal Dresden Study of Parenting, Work, and Mental Health. The survey asked about relationship satisfaction two months before the birth of the child, eight weeks postpartum, 14 months postpartum, and two years postpartum; the eight weeks postpartum check-in also asked about the child's temperament and biological sex.

The first survey check-in collected the demographic information studied. Having a child was associated with a decline in relationship satisfaction for both first- or second-time fathers. However, first-time fathers showed a higher level of relationship satisfaction before birth, and a steeper decline in satisfaction after birth. At eight weeks postpartum, first-time fathers still tended to report higher relationship satisfaction than second-time fathers, but satisfaction continued to decline for first-time fathers up until 14 months postpartum. In contrast, second-time fathers tended to report an increase in relationship satisfaction by 14 months that continued through the two year check-in. During both these points, second-time fathers had higher relationship satisfaction scores than first-time fathers -- scores which had returned to their original baseline levels. This study is the first to show this type of satisfaction increase, which has not been reported in studies of second-time mothers. This study found no significant association between reported relationship satisfaction and the other variables studied besides relationship duration: couples in longer relationships tended to report lower relationship satisfaction initially.

The authors suggest that fathers becoming parents for the first time should be prepared for expected changes in their relationship -- and know that, should they choose to have another child, the changes a newborn brings will likely be easier to weather.

The authors add: "The transition to parenthood can negatively affect the relationship satisfaction of fathers, more so for first than for second-time fathers, however, this can recover over time. Preparation and anticipation may be key."

https://www.sciencedaily.com/releases/2023/08/230830151756.htm

Researchers identify the link between memory and appetite in the human brain to explain obesity

August 30, 2023

Science Daily/University of Pennsylvania School of Medicine

Disrupted connections between memory and appetite regulating brain circuits are directly proportional to body mass index (BMI), notably in patients who suffer from disordered or overeating that can lead to obesity, such as binge eating disorder (BED), according to new research from the Perelman School of Medicine at the University of Pennsylvania. Published today in Nature, the research notes that individuals who are obese have impaired connections between the dorsolateral hippocampus (dlHPC) and the lateral hypothalamus (LH), which may impact their ability to control or regulate emotional responses when anticipating rewarding meals or treats.

"These findings underscore that some individual's brains can be fundamentally different in regions that increase the risk for obesity," senior author, Casey Halpern, MD, an associate professor of Neurosurgery and Chief of Stereotactic and Functional Neurosurgery at Penn Medicine and the Corporal Michael J. Crescenz Veterans Affairs Medical Center. "Conditions like disordered eating and obesity are a lot more complicated than simply managing self-control and eating healthier. What these individuals need is not more willpower, but the therapeutic equivalent of an electrician that can make right these connections inside their brain."

The dlHPC is located in the region of the brain that processes memory, and the LH is in the region of the brain that is responsible for keeping the body in a stable state, called homeostasis. Previous research has found an association with loss of function in the human hippocampus in individuals with obesity and related disordered eating, like BED. However, outside of imaging techniques such as magnetic resonance imaging (MRI), the role of the hippocampus has been difficult to study in humans with obesity and related eating disorders.

In this study, researchers were able to evaluate patients whose brains were already being monitored electrically in the Epilepsy Monitoring Unit. Researchers monitored brain activity as patients anticipated and then received a sweet treat (a chocolate milkshake). They found that both the dlHPC and the LH activated simultaneously when participants anticipated receiving the rewarding meal. These researchers confirmed using stimulation techniques pioneered by coauthors, Kai Miller, MD, PhD, and Dora Hermes Miller, PhD, from Mayo Clinic, that this specific zone of the hippocampus, the dlHPC, and LH exhibited extremely strong connectivity, as well.

In individuals with obesity, researchers found that the impairment of this hypothalamus-hippocampus circuit was directly proportional to their BMI. That is, in participants with a high BMI, the connection was even more disturbed.

To further validate the connection, Halpern's team used a technique called "brain clearing," to analyze brain tissue. The technique revealed melanin-concentrating hormone, a hormone known to regulate feeding behavior that is produced in the LH. They found the presence of MCH in the dlHPC, and nowhere else, confirming a link between the two regions.

"The hippocampus has never been targeted to treat obesity, or the disordered eating that can sometimes cause obesity," said Halpern. "We hope to be able to use this research to both identify which individuals who are likely to develop obesity later in life, and to develop novel therapies -- both invasive and not -- to help improve function of this critical circuit that seems to go awry in patients who are obese."

https://www.sciencedaily.com/releases/2023/08/230830131943.htm

Lengthy screen time associated with childhood development delays

August 30, 2023

Science Daily/Tohoku University

How much is adequate screen time for a child? It is the question at the forefront of many parents' minds. Now, a recent cohort study has found that the amount of screen time spent by one-year-olds is associated with developmental delays.

The amount of screen time spent by one-year-olds is associated with developmental delays. This finding, by researchers at Tohoku University, with collaborators at Hamamatsu University School of Medicine, was published in the journal JAMA Pediatrics.

The research examined 7,097 mother-child pairs participating in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study. Each child's screen time exposure was assessed using parental questionnaires, covering viewing of televisions, video game displays, tablets, mobile phones and other electronic devices with visual displays.

The children in the study were almost evenly split between boys (51.8%) and girls (48.2%). Their screen time exposure was assigned to the categories of less than one hour (48.5% of subjects), from one to less than two hours (29.5%), from two to less than four hours (17.9%), and four or more hours (4.1%).

The children's development was assessed at two and four years of age in the five domains of communication, gross motor, fine motor, problem solving, and personal and social skills. Previous studies in the field have generally not broken development down into different domains, therefore offering a less refined view.

The association between screen time at age one and later developmental delay was assessed using an established statistical technique, revealing a dose-response association; meaning that the level of developmental delay (the response) was correlated to the amount (dose) of screen time.

For the children aged two, increased screen time when aged one was associated with developmental delays in all domains apart from gross motor skills. By the age of four however, increased screen time was associated with developmental delays in only the communication and problem-solving domains.

"The differing levels of developmental delays in the domains, and the absence of any detected delay in some of them at each stage of life examined, suggests that the domains should be considered separately in future discussions of the association between screen time and child development," says Tohoku University epidemiologist Taku Obara, corresponding author of the research article.

One reason for undertaking this study was recent evidence published by the World Health Organization and the American Academy of Pediatrics suggesting that only a minority of children are meeting guidelines for limiting screen time exposure. The guidelines were designed to ensure that children engage in sufficient physical activity and social interaction.

"The rapid proliferation of digital devices, alongside the impact of the COVID pandemic, has markedly increased screen time for children and adolescents, but this study does not simply suggest a recommendation for restricting screen time. This study suggests an association, not causation between screen time and developmental delay" says Obara. "We use the term 'delay' in accordance with previous research, but it is debatable whether this difference in development is really a 'delay' or not. We would like to gain deeper insight in future studies by examining the effects of different types of screen exposure."

https://www.sciencedaily.com/releases/2023/08/230830131903.htm

Stress and insomnia linked to irregular heart rhythms after menopause

August 30, 2023

Science Daily/American Heart Association

A study of more than 83,000 questionnaires by women ages 50-79, found more than 25% developed irregular heart rhythms, known as atrial fibrillation, which may increase their risk for stroke and heart failure

After menopause an estimated 1 in 4 women may develop irregular heart rhythms -- known as atrial fibrillation -- in their lifetime, with stressful life events and insomnia being major contributing factors, according to new research published today in the Journal of the American Heart Association, an open access, peer-reviewed journal of the American Heart Association.

Atrial fibrillation may lead to blood clots, stroke, heart failure or other cardiovascular complications. It primarily affects older adults, and more than 12 million people in the U.S. are expected to develop atrial fibrillation by 2030, according to the American Heart Association.

"In my general cardiology practice, I see many postmenopausal women with picture perfect physical health who struggle with poor sleep and negative psychological emotional feelings or experience, which we now know may put them at risk for developing atrial fibrillation," said lead study author Susan X. Zhao, M.D., a cardiologist at Santa Clara Valley Medical Center in San Jose, California. "I strongly believe that in addition to age, genetic and other heart-health related risk factors, psychosocial factors are the missing piece to the puzzle of the genesis of atrial fibrillation."

Researchers reviewed data from more than 83,000 questionnaires by women ages 50-79 from the Women's Health Initiative, a major U.S. study. Participants were asked a series of questions in key categories: stressful life events, their sense of optimism, social support and insomnia. Questions about stressful life events addressed topics such as loss of a loved one; illness; divorce; financial pressure; and domestic, verbal, physical or sexual abuse. Questions about sleeping habits focused on if participants had trouble falling asleep, wake up several times during the night and overall sleep quality, for example. Questions about participants' outlook on life and social supports addressed having friends to talk with during and about difficult or stressful situations; a sense of optimism such as believing good things are on the horizon; and having help with daily chores.

During approximately a decade of follow-up, the study found:

• About 25% or 23,954 women developed atrial fibrillation.

• A two-cluster system (the stress cluster and the strain cluster).

• For each additional point on the insomnia scale, there is a 4% higher likelihood of developing atrial fibrillation. Similarly, for each additional point on the stressful life event scale, there is a 2% higher likelihood of having atrial fibrillation.

"The heart and brain connection has been long established in many conditions," Zhao said. "Atrial fibrillation is a disease of the electrical conduction system and is prone to hormonal changes stemming from stress and poor sleep. These common pathways likely underpin the association between stress and insomnia with atrial fibrillation."

Researchers noted that stressful life events, poor sleep and feelings, such as depression, anxiety or feeling overwhelmed by one's circumstances, are often interrelated. It's difficult to know whether these factors accumulate gradually over the years to increase the risk of atrial fibrillation as women age.

Chronic stress has not been consistently associated with atrial fibrillation, and the researchers note that a limitation of their study is that it relied on patient questionnaires utilized at the start of the study. Stressful life events, however, though significant and traumatic, may not be long lasting, Zhao notes. Further research is needed to confirm these associations and evaluate whether customized stress-relieving interventions may modify atrial fibrillation risk.

Study details and background:

• Participants were recruited between 1994 and 1998.

• The average age of the 83,736 women included in the study was about 64 years old. Approximately 88% of the group were women who self-identified as white; 7.2% identified as Black women; and 2.9% self-identified as Hispanic women.

• As women live longer, they may face higher risk and poorer outcomes associated with atrial fibrillation. While high blood pressure, obesity, Type 2 diabetes and heart failure are recognized risk factors, more research is needed about how the exposure to psychosocial stress and overall emotional well-being over time may affect the potential development of atrial fibrillation.

https://www.sciencedaily.com/releases/2023/08/230830131847.htm