Stress slows the immune response in sick mice

April 28, 2021

Science Daily/Cell Press

The neurotransmitter noradrenaline, which plays a key role in the fight-or-flight stress response, impairs immune responses by inhibiting the movements of various white blood cells in different tissues, researchers report April 28th in the journal Immunity. The fast and transient effect occurred in mice with infections and cancer, but for now, it's unclear whether the findings generalize to humans with various health conditions.

"We found that stress can cause immune cells to stop moving and prevents immune cells from protecting against disease," says senior study author University of Melbourne's Scott Mueller (@SMuellerLab) of the Peter Doherty Institute for Infection and Immunity (Doherty Institute). "This is novel because it was not known that stress signals can stop immune cells from moving about in the body and performing their job."

One main function of the sympathetic nervous system (SNS) is to coordinate the fight-or-flight stress response -- a group of changes that prepare the body to fight or take flight in stressful or dangerous situations to protect itself from possible harm. Most tissues, including the lymph nodes and spleen, are innervated by SNS fibers. Stress-induced activation of the SNS can suppress immune responses, but the underlying mechanisms have been poorly characterized. "We hypothesized that SNS signals might modify the movement of T cells in tissues and lead to compromised immunity," Mueller says.

White blood cells, also known as leukocytes, travel constantly throughout the body and are highly motile within tissues, where they locate and eradicate pathogens and tumors. Although the movement of leukocytes is critical for immunity, it has not been clear how these cells integrate various signals to navigate within tissues. "We also speculated that neurotransmitter signals might be a rapid way to modulate leukocyte behavior in tissues, in particular during acute stress that involves increased activation of the SNS," Mueller says.

To test this idea, the researchers used advanced imaging to track the movements of T cells in mouse lymph nodes. Within minutes of being exposed to noradrenaline, T cells that had been rapidly moving stopped in their tracks and retracted their arm-like protrusions. This effect was transient, lasting between 45 and 60 minutes. Localized administration of noradrenaline in the lymph nodes of live mice also rapidly halted the cells. Similar effects were observed in mice that received noradrenaline infusions, which are used to treat patients with septic shock -- a life-threatening condition that occurs when infection leads to dangerously low blood pressure. This finding suggests that therapeutic treatment with noradrenaline might impair leukocyte functions.

"We were very surprised that stress signals had such a rapid and dramatic effect on how immune cells move," Mueller says. "Since movement is central to how immune cells can get to the right parts of the body and fight infections or tumors, this rapid movement off-switch was unexpected."

Other experiments revealed that SNS signals inhibit the migration of distinct immune cells, including B cells and dendritic cells, exerting these effects in different tissues such as skin and liver. Additional results suggest that the effects of SNS activation on cell motility may be mediated by the constriction of blood vessels, reduced blood flow, and oxygen deprivation in tissues, resulting in an increase in calcium signaling in leukocytes.

"Our results reveal that an unanticipated consequence of modulation of blood flow in response to SNS activity is the rapid sensing of changes in oxygen by leukocytes and the inhibition of motility," Mueller says. "Such rapid paralysis of leukocyte behavior identifies a physiological consequence of SNS activity that explains, at least in part, the widely observed relationship between stress and impaired immunity."

Moreover, SNS signals impaired protective immunity against pathogens and tumors in various mouse models, decreasing the proliferation and expansion of T cells in the lymph nodes and spleen. For example, treatment with SNS-stimulating molecules rapidly stopped the movements of T cells and dendritic cells in mice infected with herpes simplex virus 1 and reduced virus-specific T cell recruitment to the site of the skin infection. Similar effects were observed in mice with melanoma and in mice infected with a malarial parasite.

"Our data suggest that SNS activity in tissues could impact immune outcomes in diverse diseases," Mueller says. "Further insight into the impact of adrenergic receptor signals on cellular functions in tissues may inform the development of improved treatments for infections and cancer."

The degree to which SNS activation affects leukocyte behavior or disease outcomes in humans remains to be determined. Notably, increased SNS activity is prominent in patients with obesity and heart failure, while psychological stress can cause blood vessel constriction in patients with heart disease. An unappreciated impact of increased SNS activity, particularly in individuals with underlying health conditions, might be impaired leukocyte behavior and functions. The findings may also have important health implications for patients who use SNS-activating drugs to treat diseases such as heart failure, sepsis, asthma, and allergic reactions.

Moving forward, the researchers will further examine the mechanisms by which immune cells are affected by SNS stress signals and explore relevant strategies to boost anti-cancer responses in patients. "This knowledge will allow us to test the impact of drugs that block the sympathetic stress pathway, such as beta blockers, on the outcomes of vaccination and cancer treatments," Mueller says. "These types of drugs might be safe treatment options for patients where stress could contribute to poor immune function."

https://www.sciencedaily.com/releases/2021/04/210428113807.htm

Research shows consuming prebiotic supplements once a day has a positive impact on anxiety levels

April 27, 2021

Science Daily/University of Surrey

In a paper published in the journal Scientific Reports, researchers from Surrey investigated whether the daily consumption of a prebiotic food supplement could improve overall wellbeing in a group of 18 to 25 year-olds. The study found that those who received a daily dose of prebiotics improved mental wellbeing by reducing anxiety levels and had better gut health than the control group.

Researchers studied a group of 64 healthy female participants with no current or previous clinical diagnoses of anxiety. Participants received either a daily dose of the prebiotic galacto-oligosaccharides (GOS) or a placebo for 28 days.

All those involved in the trial completed surveys about their health experiences, including mood, anxiety and sleep quality and provided a stool sample for gut microbiome sequencing analysis.

Dr Kathrin Cohen Kadosh, Reader in Developmental Cognitive Neuroscience at the University of Surrey and Head of the Social Brain and Development Lab, said:

"This new research marks a significant step forward in that we were able to show that we can use a simple and safe food supplement such as prebiotics to improve both the abundance of beneficial gut bacteria in the gut and to improve mental health and wellbeing in young women."

Dr Nicola Johnstone, Research Fellow from the University of Surrey, said:

"This is an exciting study that brings together different dimensions in mental health research; finding prebiotic effects in a sub-clinical group shows promise for translational clinical research on multiple markers of mental health."

https://www.sciencedaily.com/releases/2021/04/210427122408.htm

Men's loneliness linked to an increased risk of cancer

April 27, 2021

Science Daily/University of Eastern Finland

A recent study by the University of Eastern Finland shows that loneliness among middle-aged men is associated with an increased risk of cancer. According to the researchers, taking account of loneliness and social relationships should thus be an important part of comprehensive health care and disease prevention. The findings were published in Psychiatry Research.

"It has been estimated, on the basis of studies carried out in recent years, that loneliness could be as significant a health risk as smoking or overweight. Our findings support the idea that attention should be paid to this issue," Project Researcher Siiri-Liisi Kraav from the University of Eastern Finland says.

The study was launched in the 1980s with 2,570 middle-aged men from eastern Finland participating. Their health and mortality have been monitored on the basis of register data up until present days. During the follow-up, 649 men, i.e. 25% of the participants, developed cancer, and 283 men (11%) died of cancer. Loneliness increased the risk of cancer by about ten per cent. This association with the risk of cancer was observed regardless of age, socio-economic status, lifestyle, sleep quality, depression symptoms, body mass index, heart disease and their risk factors. In addition, cancer mortality was higher in cancer patients who were unmarried, widowed or divorced at baseline.

"Awareness of the health effects of loneliness is constantly increasing. Therefore, it is important to examine, in more detail, the mechanisms by which loneliness causes adverse health effects. This information would enable us to better alleviate loneliness and the harm caused by it, as well as to find optimal ways to target preventive measures."

https://www.sciencedaily.com/releases/2021/04/210427094811.htm

Finding A Physical Therapist That Can Help You Heal

Guest Post: John Mullen, Training Cor, Santa Clara CA

Pain doesn't have to be a part of life, but it doesn't have to be. You can end the pain from long-term injuries and tension. If a physical therapist is what you need, you shouldn't wait for the pain to worsen.  There are many injuries related to sports, activity from exercising, or injuries from accidents. Whatever the case may be, a physical therapist will be able to help you heal your injuries. 

Price

One thing to consider is how it will affect your wallet. Finding a physical therapist that can help you heal shouldn't cause you to go broke. What they should do is clarify your liability while establishing the cost at the outset and establishing how you will be able to pay. Taking any form of payment will be standard and offer plans to ensure that you have an option you can utilize. Most therapy services are usually covered by your insurance as well.

Activities You Can Utilize

Physical therapy centers will each have unique and individualized programs, but they will also have activities in place for you to utilize to help yourself heal and gain strength. These can include things like the following.

• Rock climbing

• Soccer

• Swimming

• Bicycling

• Weight loss

Committed to helping you in every way, the activities can strengthen joints and troubled areas. For example, swimming is easier on the knees than other activities and is often recommended to help support them. 

Areas That Can Be Treated

There are many different areas on your body that can be injured. Another issue to consider is what happens post-partum. Luckily, a proper center will be able to take care of you during that time as well. Some of the different areas that the treatment center can help you with are these.

• Hips

• Knees

• Feet

• Ankles

• Neck

It might surprise you, but incontinence is an issue that centers work with as well. In many cases, muscle exercises can help strengthen you and help with this particular issue, but they will help you heal in this way. 

Choosing The Right Option

When you are looking for someone to help you heal, finding someone you can trust to give you the best treatment is vital. Make the best decision for yourself, and know that you know yourself better than anyone else. The proper therapist will put your needs first while helping you get stronger. 

One in five American adults experience chronic pain

April 20, 2021

Science Daily/Brigham and Women's Hospital

Chronic pain is among the most common chronic conditions in the United States, but estimates of its prevalence and impact vary widely. In 2019, the National Center for Health Statistics of the Centers for Disease Control and Prevention added a new set of questions relating to pain to its National Health Interview Survey (NHIS), a large household-based annual survey that offers valuable insights into the health statuses of U.S. adults nationwide. In an article published in Pain, researchers from Brigham and Women's Hospital and Mass Eye and Ear report that 50.2 million (20.5 percent) U.S. adults experience chronic pain based on analysis of the new NHIS data. They estimated the total value of lost productivity due to chronic pain to be nearly $300 billion annually.

"Chronic pain is a serious condition that affects millions of Americans," said corresponding author R. Jason Yong, MD, MBA, medical director of the Pain Management Center at the Brigham and associate chief of pain in the Department of Anesthesiology, Perioperative, and Pain Medicine. "Other studies have touched on this fact, but data from pain clinics, hospitals and other providers tends to only provide information on people seeking out medical attention. Having the NHIS data to validate previous studies is incredibly impactful."

The authors found that respondents with chronic pain reported missing significantly more workdays compared to those without chronic pain (10.3 days versus 2.8). They used these figures to quantify the total economic impact of chronic pain on Americans, which they estimated to be $79.9 billion in lost wages. Those with chronic pain also reported more limitations to their engagement in social activities and activities of daily living. Back, hip, knee and foot pain were the most common sources of pain reported, and physical therapy and massage therapy were most commonly sought as treatments.

"The impetus for our study arose from the day-to-day clinical finding that many of our chronic sinusitis patients also reported headache, migraine and other forms of chronic pain," said senior author Neil Bhattacharyya, MD, MA, FACS, professor of Otolaryngology -- Head and Neck Surgery at Mass Eye and Ear. "We decided to look at the bigger picture of chronic pain, and we were somewhat surprised at the large-scale presence of chronic pain in the US."

The 2019 NHIS included data from 31,997 adults across the nation. When the data was first published in May, investigators decided to focus their initial analysis on ascertaining national estimates of prevalence and impact, but plan to conduct further analysis of other questions included in the survey. This may reveal more specific trends related to pain and its treatment across the U.S., especially regarding opioid use.

"Given the overall scale and impact of pain on Americans, we see that a multimodal, multidisciplinary approach to treating pain is even more important than what we have been emphasizing over the past few decades," Yong said. "Pain medicine is relatively young as a field, and it encompasses specialties including emergency medicine, anesthesia, psychiatry, neurology, physiatry and radiology. We need all of the tools in our armamentarium to treat patients suffering from chronic pain."

https://www.sciencedaily.com/releases/2021/04/210420092901.htm

Disrupted sleep is linked to increased risk of early death, particularly in women

April 19, 2021

Science Daily/European Society of Cardiology

For the first time, a study has shown a clear link between the frequency and duration of unconscious wakefulness during night-time sleep and an increased risk of dying from diseases of the heart and blood vessels, and death from any cause, particularly in women.

The study of 8001 men and women, which is published today (Tuesday) in the European Heart Journal, found that women who experienced unconscious wakefulness most often and for longer periods of time had nearly double the risk of dying from cardiovascular disease during an average of between 6 and 11 years' follow-up, when compared to the risk in general female population. The association was less clear in men, and their risk of cardiovascular death increased by just over a quarter compared to the general male population.

Unconscious wakefulness, also known as cortical arousal, is a normal part of sleep. It occurs spontaneously and is part of the body's ability to respond to potentially dangerous situations, such as noise or breathing becoming obstructed. Pain, limb movements, trauma, temperature and light can also be triggers.

Dominik Linz, associate professor in the cardiology department at Maastricht University Medical Center (The Netherlands), explained: "A common trigger for nocturnal arousals is obstructive sleep apnoea when breathing stops and the arousal system ensures the activation of our body to change our sleep position and to reopen the upper airway. Another cause of arousals can be 'noise pollution' during the night by, for example, night-time aircraft noise. Depending on the strength of the arousal, a person might become consciously aware of the environment, but often that is not the case. Typically, people will feel exhausted and tired in the morning because of their sleep fragmentation but will not be aware of the individual arousals."

Previous research has shown that sleep duration, either too short or too long, is associated with increased risks of death from cardiovascular or other causes. However, until now, it was unknown whether there was also a link with the arousal burden (a combination of the number of arousals and their duration) during a night's sleep and the risk of death.

In a collaboration between a team led by associate professor Mathias Baumert from the School of Electrical and Electronic Engineering at the University of Adelaide (Australia) and Prof. Linz, researchers looked at data from sleep monitors worn overnight by men and women taking part in one of three studies: 2782 men in the Osteoporotic Fractures in Men Sleep Study (MrOS), 424 women in the Study of Osteoporotic Fractures (SOF), and 2221 men and 2574 women in the Sleep Heart Health Study (SHHS). The average ages in the studies were 77, 83 or 64 years, respectively. The participants were followed up over a period of several years, which ranged from an average of six years (SOF) to 11 years (MrOS).

After adjusting for factors that could affect the results such as total sleep duration, age, medical history, body mass index (BMI) and smoking habits, the researchers found that women had an arousal burden that was lower than men. However, those who had an arousal burden that accounted for more than 6.5% of their night's sleep had a greater risk of dying from cardiovascular disease than women with a lower arousal burden: double the risk in SOF and 1.6 times the risk in SHHS. Their risk of dying from all causes was also increased by 1.6 times in SOF and 1.2 times in SHHS.

Taking the women from both studies together, those with an arousal burden of more than 6.5% had a 12.8% risk of dying from cardiovascular disease, nearly double that of women of a similar age in the general population who had a risk of 6.7%. The risk of dying from any cause was 21% among women in the general population, which increased to 31.5% among women in the two studies with an arousal burden of more than 6.5%

Men with an arousal burden accounting for more than 8.5% of their night's sleep had 1.3 times greater risk of dying from cardiovascular disease (MrOS) or any cause (SHHS), compared to men with lower arousal burdens, but findings for increased risk of death from any cause in MrOS or cardiovascular disease in SHHS were not statistically significant.

When the researchers looked at all the men in both studies, those with an arousal burden of more than 8.5% had a risk of 13.4% and 33.7% of dying from cardiovascular disease or any cause, respectively, compared to the risk in the general population of men of similar ages of 9.6% and 28%, respectively.

Prof. Linz said: "It is unclear why there is a difference between men and women in the associations, but there are some potential explanations. The triggers causing an arousal or the body's response to arousal may differ in women compared to men. This may explain the relatively higher risk of cardiovascular death in women. Women and men may have different compensatory mechanisms for coping with the detrimental effects of arousal. Women may have a higher arousal threshold and so this may result in a higher trigger burden in women compared to men."

He said that older age, BMI and the severity of sleep apnoea increase arousal burdens. "While age cannot be changed, BMI and sleep apnoea can be modified and may represent an interesting target to reduce arousal burdens. Whether this will translate into lower risks of dying from cardiovascular disease warrants further study. For me as a physician, a high arousal burden helps to identify patients who may be at higher risk of cardiovascular disease. We need to advise our patients to take care of their sleep and practice good sleep 'hygiene'. Measures to minimise noise pollution during the night, lose weight and treat sleep apnoea could also help to reduce the arousal burden."

Prof. Baumert said: "In order to include assessment of arousal burdens into routine strategies for reducing the risk of cardiovascular disease, we need easily scalable, widely accessible and affordable techniques to estimate the duration and fragmentation of sleep and to detect arousals. Wearable devices for measuring activity and changes in breathing patterns may provide important information."

Limitations of the study include that it was conducted in older, mainly white people and so its findings cannot be extrapolated to other races or younger men and women. The researchers did not consider the possible effect of medications; monitoring of the participants' sleep was conducted on a single night and so does not take account of night-to-night variations. Finally, it can only show there is an association between greater sleep arousal burden and increased risk of death, not that sleep arousals cause the increased risk.

In an accompanying editorial Professor Borja Ibáñez, clinical research director at the Centro Nacional de Investigaciones Cardiovasculares Carlos III, Madrid (Spain), and colleagues, who were not involved in the research, write that a strength of the study is that the arousal burden was measured objectively with sleep monitors, rather than being self-reported by the participants. They point out that disruption of the body's natural circadian rhythm is known to be involved in the development of often undetected fat accumulation in arteries and this could be a possible mechanism for the increase in the risk of cardiovascular problems.

They continue: "Even though many knowledge gaps on the relationship between sleep and CVD [cardiovascular disease] remain to be studied in the coming years, this study provides solid evidence supporting the importance of sleep quality for a better CV health. Further evidence combining comprehensive sleep evaluation with biological sampling and long-term follow-ups will be desirable . . . What remains to be determined is whether an intervention aiming at improving sleep quality is able to reduce the incidence of CV events and mortality. While awaiting these trials, we wish you sweet dreams."

https://www.sciencedaily.com/releases/2021/04/210419195248.htm

Can financial stress lead to physical pain in later years?

Researchers found that early stress can have an impact decades later

April 15, 2021

Science Daily/University of Georgia

Financial stress can have an immediate impact on well-being, but can it lead to physical pain nearly 30 years later? The answer is yes, according to new research from University of Georgia scientists.

The study, published in Stress & Health, reveals that family financial stress in midlife is associated with a depleted sense of control, which is related to increased physical pain in later years.

"Physical pain is considered an illness on its own with three major components: biological, psychological and social," said Kandauda A.S. Wickrama, first author and professor in the College of Family and Consumer Sciences. "In older adults, it co-occurs with other health problems like limited physical functioning, loneliness and cardiovascular disease."

Most pain research is neurological, but it's important to also connect it to stressful family experiences, according to the researchers.

"Dr. Wickrama and I are both interested in the context surrounding families and how that context impacts the relational, physical and mental health of the individuals in the family," said lead author Catherine Walker O'Neal, associate research scientist in the College of Family and Consumer Sciences. "Finances are an important component of our work because it's such a relevant contextual stressor families face."

The authors used data from the Iowa Youth and Family Project, a longitudinal study that provides 27 years of data on rural families from a cluster of eight counties in north-central Iowa. The data was collected in real time from husbands and wives in 500 families who experienced financial problems associated with the late 1980s farm crisis. Most of the individuals are now over 65 years old, and the couples are in enduring marriages -- some as long as 45 years.

Even after the researchers controlled for concurrent physical illnesses, family income and age, they found a connection between family financial hardship in the early 1990s and physical pain nearly three decades later. Additional findings from their study show it's more likely that financial strain influences physical pain, though physical pain can in turn influence financial strain through additional health care costs.

Physical pain is a biopsychosocial phenomenon, according to Wickrama. The research suggests that stressful experiences like financial strain erode psychological resources like a sense of control. This depletion of resources activates brain regions that are sensitive to stress, launching pathological, physiological and neurological processes that lead to health conditions like physical pain, physical limitations, loneliness and cardiovascular disease.

"In their later years, many complain about memory loss, bodily pain and lack of social connections," he said. "Nearly two-thirds of adults complain of some type of bodily pain, and nearly that many complain of loneliness. That percentage is going up, and the health cost for that is going up. That is a public health concern."

https://www.sciencedaily.com/releases/2021/04/210415170721.htm

New measure to predict stress resilience

April 15, 2021

Science Daily/University of Zurich

Researchers at the University of Zurich show that increased sensitivity in a specific region of the brain contributes to the development of anxiety and depression in response to real-life stress. Their study establishes an objective neurobiological measure for stress resilience in humans.

Some people don't seem to be too bothered when it comes to handling stress. For others, however, prolonged exposure to stress can lead to symptoms of anxiety and depression. While stress resilience is a widely discussed concept, it is still very challenging to predict people's individual response to increased levels of stress. Lab experiments can only go so far in replicating the chronic stress many people experience in their day-to-day lives, as stress simulated in the lab is always limited in exposure time and intensity.

It is possible, however, to observe a group of medical students who are all about to face real-life stress for an extended period -- during their six-month internship in the emergency room. This is precisely the real-life situation on which a team of researchers involving Marcus Grueschow and Christian Ruff from the UZH Zurich Center for Neuroeconomics and Birgit Kleim from the Department of Psychology and the University Hospital of Psychiatry Zurich based their study.

Stress as a response to cognitive conflict and loss of control

Before starting their internship, the subjects were given a task that required them to process conflicting information. This conflict task activates the locus coeruleus-norepinephrine (LC-NE) system, a region of the brain associated with regulating our response to stress and resolving conflict. However, the intensity of LC-NE activation -- often referred to as the "firing rate" -- varies from one person to the next.

Subjects with a higher LC-NE responsivity showed more symptoms of anxiety and depression following their emergency room internships. "The more responsive the LC-NE system, the more likely a person will develop symptoms of anxiety and depression when they're exposed to prolonged stress," Marcus Grueschow summarizes their findings.

Objective measure predicting stress resilience

With their study, the scientists have identified an objective neurobiological measure that can predict a person's stress response. This is the first demonstration that in humans, differences in LC-NE responsivity can be used as an indicator for stress resilience. "Having an objective measure of a person's ability to cope with stress can be very helpful, for example when it comes to choosing a profession. Or it could be applied in stress resilience training with neuro-feedback," Marcus Grueschow explains.

This does not mean that aspiring doctors or future police officers will all have to have their brain scanned. "There might be an even more accessible indicator for stress resilience," Christian Ruff says. Research with animals suggests that stimulation of the LC-NE system correlates with pupil dilation. "If we could establish the same causal link between pupil dilation and the LC-NE system in humans, it would open up another avenue," he adds.

https://www.sciencedaily.com/releases/2021/04/210415090715.htm

People want to improve mental health by exercising, but stress and anxiety get in the way

April 12, 2021

Science Daily/McMaster University

New research from McMaster University suggests the pandemic has created a paradox where mental health has become both a motivator for and a barrier to physical activity.

People want to be active to improve their mental health but find it difficult to exercise due to stress and anxiety, say the researchers who surveyed more than 1,600 subjects in an effort to understand how and why mental health, physical activity and sedentary behavior have changed throughout the course of the pandemic.

The results are outlined in the journal PLOS ONE.

"Maintaining a regular exercise program is difficult at the best of times and the conditions surrounding the COVID-19 pandemic may be making it even more difficult," says Jennifer Heisz, lead author of the study and an associate professor in the Department of Kinesiology at McMaster.

"Even though exercise comes with the promise of reducing anxiety, many respondents felt too anxious to exercise. Likewise, although exercise reduces depression, respondents who were more depressed were less motivated to get active, and lack of motivation is a symptom of depression," she says.

Respondents reported higher psychological stress and moderate levels of anxiety and depression triggered by the pandemic. At the same time, aerobic activity was down about 20 minutes per week, strength training down roughly 30 minutes per week, and sedentary time was up about 30 minutes per day compared to six months prior to the pandemic.

Those who reported the greatest declines in physical activity also experienced the worst mental health outcomes, the researchers reported, while respondents who maintained their physical activity levels fared much better mentally.

Researchers also found economic disparities played a role, particularly among younger adults.

"Just like other aspects of the pandemic, some demographics are hit harder than others and here it is people with lower income who are struggling to meet their physical activity goals," says Maryam Marashi, a graduate student in the Department of Kinesiology and co-lead author of the study. "It is plausible that younger adults who typically work longer hours and earn less are lacking both time and space which is taking a toll."

After analysing the data, the researchers designed an evidence-based toolkit which includes the following advice to get active:

• Adopt a mindset: Some exercise is better than none.

• Lower exercise intensity if feeling anxious.

• Move a little every day.

• Break up sedentary time with standing or movement breaks.

• Plan your workouts like appointments by blocking off the time in your calendar.

"Our results point to the need for additional psychological supports to help people maintain their physical activity levels during stressful times in order to minimize the burden of the pandemic and prevent the development of a mental health crisis," says Heisz.

https://www.sciencedaily.com/releases/2021/04/210412121216.htm

Dietary cocoa improves health of obese mice; likely has implications for humans

April 14, 2021

Science Daily/Penn State

Supplementation of cocoa powder in the diet of high-fat-fed mice with liver disease markedly reduced the severity of their condition, according to a new study by Penn State researchers, who suggest the results have implications for people.

Cocoa powder, a popular food ingredient most commonly used in the production of chocolate, is rich in fiber, iron and phytochemicals reported to have positive health benefits, including antioxidant polyphenols and methylxanthines, noted study leader Joshua Lambert, professor of food science in the College of Agricultural Sciences.

"While it is typically considered an indulgence food because of its high sugar and fat content, epidemiological and human-intervention studies have suggested that chocolate consumption is associated with reduced risk of cardio-metabolic diseases including stroke, coronary heart disease and Type 2 diabetes," Lambert said. "So, it made sense to investigate whether cocoa consumption had an effect on non-alcohol-related fatty liver disease, which is commonly associated with human obesity."

This study has several strengths, Lambert explained. It used a commercially available cocoa product at a "physiologically achievable dose" -- meaning its equivalent could be duplicated by humans. "Doing the calculations, for people it works out to about 10 tablespoons of cocoa powder a day," he said. "Or, if you follow the directions on the Hershey's box of cocoa powder, that's about five cups of hot cocoa a day."

The high-fat-fed mouse is a well-established, diet-induced model of obesity, Lambert added. By waiting until mice were already obese before beginning cocoa treatment, researchers were able to test the protective effects of cocoa in a model that better simulates the current public health situation related to non-alcohol-related fatty liver disease.

That's important, Lambert pointed out, because a significant proportion of the world's population has preexisting obesity and non-alcohol-related fatty liver disease. "Given the high proportion of people in the United States and other parts of the world with obesity, there is a need to develop potentially effective dietary interventions rather than just preventive agents," he said.

For this study, researchers examined changes in fatty liver disease, markers of oxidative stress, antioxidant response and cell damage in high-fat-fed obese mice treated with a diet supplemented with 80 mg cocoa powder per gram of food -- roughly a pinch per quarter teaspoon -- for eight weeks.

In findings recently published in the Journal of Nutritional Biochemistry, the researchers reported that cocoa-treated mice gained weight at a 21% lower rate and had smaller spleen weights -- indicating less inflammation -- than the high-fat-fed control mice. At the end of the study, mice fed the cocoa-powder-supplemented diet had 28% less fat in their livers than the control mice. Cocoa-treated mice also had 56% lower levels of oxidative stress and 75% lower levels of DNA damage in the liver compared to high-fat-fed control mice.

The mechanisms by which cocoa imparts health benefits are not well understood, but previous studies in Lambert's lab showed that extracts from cocoa and some of the chemicals in cocoa powder can inhibit the enzymes that are responsible for digesting dietary fat and carbohydrate.

The result, he proposes, is that when mice get cocoa as part of their diet, these compounds in the cocoa powder prevent the digestion of dietary fat. When it can't be absorbed, the fat passes through their digestive systems. A similar process may occur with cocoa in humans, he hypothesizes.

In view of this new information about cocoa powder, Lambert is not recommending that obese people -- or anyone -- simply add five cups of hot cocoa to their daily routine and change nothing else in their diet. But he does advise, based on what he has learned in this study, to consider substituting cocoa for other foods, particularly high-calorie snack foods.

"This exchange is potentially beneficial, especially in combination with a healthy overall diet and increased physical activity," he said. "If you go to the gym and work out, and your reward is you go home and have a cup of cocoa, that may be something that helps get you off the couch and moving around."

Also involved in the research were Mingyao Sun, Yeyi Gu and Shannon Glisan, former graduate students in the Department of Food Science.

https://www.sciencedaily.com/releases/2021/04/210414154933.htm