Pet dog microbiota may protect young children from respiratory tract infections

 Children who have been in contact with dogs in early childhood are on average healthier and require fewer antibiotic courses than children without such contact. The protective association is explained, at least in part, by the spread of dog-associated microbes in the home.

In the recent study, the presence of specific dog-associated microbes in the home were linked to fewer respiratory tract infections, fewer antibiotic courses and more healthy weeks during the child’s first year of life. The richness and diversity are higher in homes with a dog than in homes without a dog, but these general characteristics of the microbiota were not associated with the incidence of respiratory tract infections or morbidity in the child.

The study shows that certain dog-associated microbes or their combinations can explain up to one quarter of the protective effect of dog ownership on children’s respiratory tract infections, antibiotic use and the number of healthy weeks during the first year of life.

The protective effect of a dog ownership remained also after accounting for other factors known to influence childhood infection risk, including family size, living environment and exposure to tobacco smoke. In addition to the dog’s microbiota, a more outdoor-oriented lifestyle in dog-owning families, shared responsibilities related to caring for the dog and partly similar dietary habits shared among dog owners may influence the microbiota in the home and among its inhabitants, and thereby the development of the child’s resistance to pathogens. These factors were not examined in this study.

“The results strengthen our understanding that the microbial environment during early childhood plays an important role in the development of child’s immune system. It has been suggested that in the future it may be possible to modify the home microbiota in ways that promote health. Our study shows that dog ownership already does this today,” says paediatrician Jenni Mäki.

“Respiratory tract infections in early childhood are a significant risk factor for asthma. When some of children’s respiratory tract infections can be prevented with dog-associated microbes, this may also reduce the child’s risk of developing asthma later in life,” says chief researcher Anne Karvonen.

High intensity exercise key to maintaining healthy bones

 When it comes to maintaining healthy bones, how intensely we exercise may matter more than how much we exercise, according to researchers at Semmelweis University. Their study, published in Sports Medicine – Open, found that bone formation was stimulated most effectively by activities involving explosive movements, rapid changes of direction, and turning. The findings could help improve exercise programs designed to maintain bone health and prevent osteoporosis. 

Researchers at Semmelweis University analyzed the results of 24 clinical studies involving a total of 1,238 healthy adult participants. Rather than tracking changes in bone mineral density, the studies measured substances in the blood that indicate whether the body is actively building new bone tissue. These so-called biomarkers can reflect the effects of exercise within just a few weeks, providing feedback much earlier than bone density measurements.  

“What makes our study unique is that we examined not only the type of exercise – whether endurance, resistance, or combined training – but also exercise intensity, frequency, and duration. Our goal was to determine which forms of exercise stimulate bone metabolism most effectively and which appear to be less beneficial from this perspective,” said dr. Péter Ferdinandy, Vice-Rector for Science and Innovations at Semmelweis University and senior author of the study. 

The most effective activities were high-intensity sports involving frequent explosive movements, rapid changes of direction, and turning. Recreational football and handball, for example, were associated with increases of up to 45–46 percent in the levels of substances linked to bone formation. In contrast, walking, step aerobics, and traditional gym-based resistance exercises were generally less effective.  

What should you keep in mind?
It is important not to start a high-intensity exercise program suddenly or without proper preparation. This is particularly true for people with cardiovascular, musculoskeletal, or metabolic diseases, as well as those living with osteoporosis. Before beginning a new type of exercise or a more demanding training program, they should consult their treating physician, general practitioner, or a sports medicine specialist to ensure that the activity and its intensity are appropriate for their individual health status.

“The most surprising finding was that resistance training did not produce a significant effect on markers of bone metabolism, even though several professional guidelines recommend this type of exercise for maintaining bone health. Likewise, low- or moderate-intensity endurance exercise, such as walking or jogging, showed no meaningful long-term effect,” explained Viktória Barna, PhD student at Semmelweis University and first author of the study.

This, of course, does not mean that walking or lower-intensity physical activity is without health benefits. However, if the goal is to keep bones strong and healthy for as long as possible, they appear to require a greater mechanical stimulus. 

“According to the World Health Organization, regular physical activity offers numerous health benefits. However, our findings suggest that low-intensity exercise alone is not sufficient to stimulate bone metabolism. High-intensity exercise may trigger early beneficial changes in bone formation, potentially helping to slow bone loss and support healthy ageing,” summarized dr. Nóra Sydó, clinical specialist and co-author of the study. 

The health stakes of feeling connected

 Calling a friend after a long day. Showing up to a neighbor's dinner when you'd rather stay home. Lingering a little longer in a conversation that didn't need to last. Such ordinary, even trivial, moments. But to psychologist Susan Charles, Associate Dean of Graduate Programs in the School of Social Ecology, they may be among the most consequential health decisions a person makes.

Charles has been awarded a $2,550,958 grant from the National Institute on Aging to investigate how the daily rhythms of feeling socially connected, or disconnected, shape the way our bodies and minds hold up over time.

Her project, “Linking Daily Dynamics of Social Connection to Physical and Cognitive Functioning,” could fundamentally change how doctors, therapists and public health officials approach loneliness and social isolation.

The health stakes of feeling connected

Most people intuitively understand that having close relationships is good for them. Decades of research confirmed it. But, Charles argues that science has been limited by looking at social connection in only one way — as a fixed trait, a general level of sociability that a person either has or doesn't have.

“Our understanding of social connection and its strong association with health is based largely on studies assessing social experiences using static, trait-like measures of general levels of thoughts and activities,” Charles notes. “Yet, feeling socially connected varies from day to day, fluctuating as much as other commonly recognized daily emotional experiences.”

In other words, the same person who feels warmly surrounded by community on Tuesday might feel profoundly alone by Thursday.

Charles believes such fluctuations may hold the key to understanding how social life gets under our skin, quite literally.

She draws a vivid picture of what this might look like in an ordinary life.

“Daily decisions to call a friend, or to go to a social function even though you are tired from a long day at work may not seem like health decisions,” Charles says, “but these times of social connection influence well-being.”

The effects, she explains, are both immediate and cumulative. A shared laugh can ease distress and trigger feelings of safety and contentment. Showing up for a regular dinner with a neighbor means you leave your house, stay physically active and engage in the kind of conversation that demands mental effort — tracking information, forming arguments, retrieving memories. Over time, those moments compound.

“Consistent positive social connection enhance health, affecting myriad health outcomes from physical symptoms to gene expression,” Charles adds.

Small daily changes, she points out, have the potential to create a “ripple effect” that contributes to longer-term outcomes — for better or for worse.

To test these ideas, Charles is turning to one of the most extraordinary longitudinal datasets in social science: the Midlife in the United States study, known as MIDUS.
The project draws on two longitudinal daily diary datasets spanning nearly 20 years. In one dataset, participants completed nightly phone interviews every day for a week, across three separate waves in 2002, 2014, and 2023. A second dataset captures two waves of daily diary data spanning about a decade, with waves beginning in 2012 and 2023.

Altogether, the study follows more than 2,900 adults ranging in age from 24 to 97.

In addition to the daily diary interviews, participants completed extensive surveys, underwent cognitive assessments and some even flew to a medical facility where they provided blood and urine samples, completed physical fitness tasks and submitted to a battery of biomarker testing.

“Any single facet of this study is interesting to study,” Charles says, “but together we have an unprecedented view into how their daily lives unfold and are related to multiple measures of cognitive, physical and mental health.”

Charles will delve deep in her search for evidence of social connection’s effects.

The professor and her research team plan to examine cortisol, often called the “stress hormone,” with chronically high levels linked to cognitive decline and poor physical health.

Charles also will analyze inflammatory markers, gene expression profiles, and even biomarkers of biological age acceleration — measures of how fast a person’s cells are aging relative to their chronological age.

The biological story she hopes to tell connects the social world to a phenomenon scientists call “inflammaging,” the age-related increase in chronic low-grade inflammation now understood to play a central role in multiple health conditions, including cardiovascular disease, diabetes, certain forms of dementia and arthritis.

“We will examine biomarkers that have been related to poorer health — chronically high inflammation, high levels of cortisol, and gene expression related to inflammation and viral load — and see how these biomarkers are related to the levels and consistency of daily social connection,” Charles explains.

If daily patterns of feeling connected, or disconnected, can be shown to move those biological needles, the implications for preventive medicine could be substantial.

Why age changes everything

The study’s age range: from young adults in their mid-20s to nonagenarians. Charles is particularly interested in how the relationship between social connection and health shifts as the body grows more vulnerable.

“We know from nearly 100 years of research that social connections are vitally important for people of all ages,” she says. “In this study, we are particularly interested in how patterns of social connection change over time in later life, and how social connections may vary in their relationship with health among people with less robust physical systems.”

As chronic illness and functional disability become more prevalent with age, she argues, the stakes of social isolation grow higher — and so does the potential benefit of meaningful daily connection.

The United States Surgeon General has called loneliness and social isolation a public health epidemic, and the COVID-19 pandemic accelerated trends toward isolation that were already underway.

Against that backdrop, Charles sees her study as doing something more than documenting a problem. She wants to change the conversation around it.

“Our research reframes a message from warning people about the risks of social isolation to acknowledging the power of positive social connections,” she says. “We will be examining different contexts to reveal when and under what circumstances social connections increase our health.”

Her goal is simple but potentially transformative: to make social connection a recognized daily health behavior, as concrete and actionable as exercise or diet.

“Social connection should be listed as a daily health behavior for everyone,” Charles says. “Every finding that links social connection to better physical and cognitive functioning will reinforce and strengthen this message, as well as identify those most at risk for both social isolation and for the health risk of lack of social connection.”

Eating a diverse range of plants everyday=better results in microbiome than a probiotic

Eating a wide variety of plants everyday could be more beneficial to the microbiome than taking a standard probiotic.

New research led by scientists from King’s College London and ZOE has discovered that consuming a daily blend with over 30 different plants resulted in increased populations of ‘favourable’ gut bacteria compared to a probiotic control.

In a randomised controlled trial, participants who consumed a supplement containing a diverse range of vegetables, fruits, nuts, seeds, herbs, spices, and mushrooms, showed increased populations of 57 species of ‘good’ bacteria of bacteria. Those in the probiotic and control groups saw changes in only 4 and 14 species, respectively.

Those consuming the blend of plants also reported increased energy and reduced hunger, digestive symptoms, constipation, heartburn, and flatulence.

In the trial, 349 adults from the UK were given a 30g daily plant supplement, known as Daily30, and compared against two comparators: a control of 28g of bread croutons, matched for energy (kcal), and a single-strain probiotic capsule containing Lactobacillus rhamnosus, a well-studied probiotic strain.

Other key findings included:

• There were significant differences in those eating the plant blend vs those in the control group, with 55% of participants in the former reporting reductions in indigestion, 35% in the severity of constipation, 18% in heartburn, and 37% in flatulence 
• 51% of participants taking the plant blend reported increased energy levels, 45% reported an increase in happiness, and 35% reported a reduction in severity of constipation, compared with the control group 
• In the plant blend group, the gut bacteria species that increased were on average those linked to favorable health markers, in comparison and the toand the  species that decreased were were linked to unfavourable health markers. This effect was not seen in either the control or probiotic groups.

A sub-group of 34 participants were given a carbohydrate-rich meal either with or without the plant blend added. Adding the plant blend resulted in participants reporting greater energy (43%), fullness (41%), meal satisfaction (22%) and reduced desire to eat (71%) and hunger (17%).

Lead author Professor Sarah Berry, Department of Nutritional Sciences at King's College London and Chief Scientist at ZOE, said: “The fact that Daily30 altered 57 distinct bacterial species in just six weeks reshapes informs informs how we should approach gut health. Rather than introducing isolated strains through a pill, these results prove we can achieve a far greater impact on the gut microbiome composition on the gut microbiome composition by nourishing our existing microbes with a diverse array of plants.

“This research suggests we should focus on plant diversity, and the role that varied fibres play in shaping the microbiome, rather than searching for a single silver bullet.”

Tim Spector, Scientific Co-Founder of ZOE and Professor of Epidemiology at King’s College London, said: "The global supplement industry is worth billions, yet much of it is built on marketing hype rather than robust science. For too long, consumers have been sold synthetic pills and ultra-processed powders as a quick fix. At ZOE, we are leading the way by backing our whole food nutrition with the world-class, rigorous research this industry desperately lacks.”

Reducing protein intake could promote healthy aging

 

Protein-fortified foods are popping up everywhere, from cereal and coffee to even protein water. But a new review covering over 350 papers on protein restriction and aging—publishing July 31 in the Cell Press journal Cell Press Blue—suggests that consuming less protein could have greater health benefits and could, in some cases, extend lifespan. The authors describe how protein restriction slows aging by improving metabolism, changing how cells respond to nutrients, reducing cellular damage, and preserving healthy cell function. 

“It's absolutely crystal clear that there are benefits of protein to muscle growth and exercise response of active individuals,” says Dudley Lamming, the paper’s corresponding author, of the University of Wisconsin-Madison. “But because most people are relatively sedentary, many people are likely consuming more protein than they actually need, which probably has negative health consequences." 

For decades, scientists have known that eating less calories can extend lifespan in many organisms and reduce the risk of age-related diseases like cancer. But maintaining a calorie-restricted diet is difficult for most people. 

Previous studies have found that eating less protein can extend the lifespan of flies and rodents without reducing their calorie consumption. Several recent clinical trials in humans have also shown that reducing protein intake can reduce weight and fat mass and improve fasting blood sugar in humans, even though protein-restricted individuals tend to eat more calories.  

But at the same time, some studies have found that eating more protein could promote weight loss and reduce age-related muscle loss in older adults when paired with exercise. Those findings prompted US authorities to update its dietary guidelines this year, recommending an increase in daily protein intake to 1.2–1.6 grams per kilogram of body weight (0.5–0.7 grams per pound), nearly doubling the previous recommendations.   

With Americans consuming more protein than ever and older adults encouraged to boost their intake, Lamming and his colleague set off to review decades of research on protein restriction and aging. Drawing on more than 350 papers, the team outlined potential mechanisms that consistently emerge across studies and may explain how protein-restricted diets could improve health and promote longevity. These mechanisms suggest that protein restriction slows aging by improving metabolism, changing how cells respond to nutrients, reducing cellular damage, and preserving healthy cell function. 

One of the key players is a hormone called fibroblast growth factor 21 (FGF21), which rises when protein intake is low. FGF21 can increase the body’s energy expenditure, improve blood sugar control, and reduce inflammation. Studies in mice have shown that animals with higher FGF21 levels lived longer than normal mice, and the benefit was more pronounced in male mice than female mice. Eating less protein raises FGF21 levels in humans as well. 

The review also highlights several amino acids, the building blocks of protein, that appear to drive many of these effects, including methionine, isoleucine, and valine. Studies show that consuming too much of these amino acids could trigger biological processes that promote growth, increasing the risk of obesity, inflammation, and other age-related diseases.  

“These studies show that the amount of protein sedentary people are eating today may have negative health consequences, at least at the population level," Lamming says. 

He adds that while some people, like pregnant women and some older adults, have higher protein needs, for most sedentary adults, protein-fortified food may not provide the health benefits people expect.  

Lamming notes that athletes often consume large amounts of protein without developing metabolic diseases. He suspects that regular exercise, perhaps by using protein to build strong healthy muscles, helps protect them from the negative health effects associated with a protein-rich diet. 

"Recent recommendations have encouraged people to eat more protein, but they've also encouraged people to exercise more," Lamming says. "We probably need to personalize protein recommendations based not just on age, but also on how physically active people are."  

Nearly 1 in 3 U.S. adults with high blood pressure may need medication

Nearly 23 million Americans with blood pressure 130/80 mm Hg or higher may be eligible for blood-pressure-lowering medications based on the 2025 American Heart Association/American College of Cardiology guideline, according to new, independent research published today in the Journal of the American Heart Association, an open access, peer-reviewed scientific journal of the American Heart Association.

The 2025 American Heart Association/American College of Cardiology High Blood Pressure guideline advises lifestyle changes — eating a healthy diet, managing weight, getting regular physical activity and reducing salt and alcohol — as a key part of treatment for high blood pressure, with medication prescribed if appropriate. The guideline also suggests healthcare professionals use the American Heart Association’s PREVENTTM (Predicting Risk of cardiovascular disease EVENTs) risk equations to calculate 10-year cardiovascular disease risk among adults (ages 30-79 without known cardiovascular disease) with high blood pressure who do not have established cardiovascular disease.

This study is one of the first detailed assessments of the 2025 guideline on high blood pressure and updated cardiovascular disease risk estimates using the PREVENT risk equations.

“Through this study, our goal was to understand how many people may qualify for treatment according to the updated recommendations in the guideline and estimate how many deaths from any cause and from cardiovascular disease may be prevented in the long term if the guideline recommendations were applied and untreated patients received care that included medication,” said study lead author Mustafa Al-Jarshawi, M.B.Ch.B., M.Sc., MRCPUK, PgCert, an academic clinical fellow in cardiology, member of the Cardiovascular Research Group at the Centre for Prognosis Research at Keele University in the United Kingdom and honorary research fellow at the Centre for Health Informatics, University of Manchester.

Researchers examined links between blood pressure treatments and rates of deaths from all causes and from cardiovascular conditions. Their analysis predicted how many lives may be saved if treatment plans outlined in the 2025 guideline were prescribed.

The data analysis found:

• 81 million U.S. adults had a diagnosis of high blood pressure. Of these, 22.8 million (28%) were guideline-eligible for therapy based on a blood pressure reading of 130/80 mm Hg or higher. 13.1 million (57%) adults were already receiving treatment for high blood pressure, while 9.7 million (43%) remained untreated. Please note: The blood pressure readings were measured during one office visit for the National Health and Nutrition Examination Survey (NHANES) collected between 2009 and 2018. The current guideline advises taking multiple readings during multiple office visits. This is an important study limitation.
• The analysis estimates that, among eligible adults, receiving blood pressure-lowering medications was associated with a 23% lower risk of dying from any cause and a 50% lower risk of dying from heart-related issues. This was compared to eligible adults who do not receive treatment.
• If treatment with medications was extended to all untreated but eligible adults, the analysis estimates approximately 200,000 all-cause deaths and 162,000 cardiovascular deaths may be prevented during the next decade.
• People eligible for high blood pressure treatment with medication who would benefit most were older, with an average age of 66, and had more health conditions, including diabetes, chronic kidney disease and other cardiovascular disease risk factors.

“What stood out most was the size of the treatment gap — more than 40% of people who were clearly eligible under the new guideline were not receiving treatment, as well as the scale of the potential benefit,” Al-Jarshawi said.

“Lifestyle modification remains the foundation of high blood pressure management. Maintaining a healthy weight, consuming a heart-healthy diet, reducing sodium intake, increasing physical activity, getting enough sleep, managing stress and limiting alcohol can meaningfully lower blood pressure and overall cardiovascular risk,” said study senior author Mamas A. Mamas, M.D, DPhil., Professor of Cardiology at Keele University and Honorary Professor of Population Health at the University of Manchester. “For many people, especially those with blood pressure under 140/90 mm Hg and no history of heart disease, stroke, chronic kidney disease or diabetes, lifestyle changes can be enough at first. If your 10-year risk of heart disease is low, with a PREVENT score under 7.5%, maintaining a healthy lifestyle can help you delay or avoid needing medication. Even if you do need medication to lower blood pressure, making lifestyle changes is important for effective treatment and overall health.”

“The 2025 guideline emphasizes a personalized approach to managing high blood pressure by considering blood pressure levels plus 10-year and 30-year overall cardiovascular disease risk. The American Heart Association’s PREVENT risk equations help to identify individuals who could benefit from treatment before a major cardiac event,” said Chair of the American Heart Association’s 2025 guideline writing committee Daniel W. Jones, M.D., FAHA.

“Controlling blood pressure is crucial for long-term health. While lifestyle changes are the foundation for better overall health, people with high blood pressure and higher risk for cardiovascular disease may also need medication to reduce the risk of serious complications from untreated high blood pressure. Healthcare professionals should assess overall cardiovascular risk and work together with their patients to combine lifestyle strategies and medication for optimal blood pressure control.” Jones, who was not involved in this study, is a past volunteer president of the American Heart Association (2007-2008) and is dean and professor emeritus of the University of Mississippi School of Medicine in Jackson, Mississippi.

Study details, background, design and limitations:

• The study had 53% male and 47% female participants, 9.4% had chronic kidney disease, 17 % had diabetes, 47% had dyslipidemia and 15% were current smokers.
• The participants self-identified as 70% white adults, 12% Black adults, 7.2% Mexican American adults, 5.8% multiracial adults and 4.2% other Hispanic adults.
• Study limitations include that researchers did not randomly assign the treatment, which means other unmeasured factors may have influenced treatment and the results. Since blood pressure was measured during a single NHANES visit and researchers examined treatment at only one point in time, the study could not capture how patients’ medication use or treatment routines may have changed over time as they worked with their healthcare teams.

 

Common antihistamines provide little meaningful benefit for eczema

 

It’s typical for someone looking for relief from dry, itchy, red and irritated skin – also known as eczema or atopic dermatitis – to turn to common allergy medications called antihistamines. New research from McMaster University, however, has found that these commonly used medications don’t make a meaningful difference in improving symptoms, and for some of the most commonly used antihistamines, they can cause harm.

Oral antihistamines are a common staple in households around the globe, with many available without a prescription. The belief is these medications will help temper down itching and disruptions to sleep caused by eczema, but clinical practice and guidelines vary in recommending for or against the potential benefits due to lack of clear evidence.

As detailed in the BMJ on July 29, 2026, researchers found that oral antihistamines do not importantly improve the outcomes that matter most in controlling eczema, and can increase the risk of cognitive impairment. To come to this conclusion, a systematic review of 47 randomized trials consisting of 6,230 children and adults with mild to severe eczema was conducted – the most comprehensive analysis to date on the topic.

“Eczema care increasingly focuses on controlling skin and immune inflammation with moisturizers, topical anti-inflammatory treatments, and whole-body treatments like phototherapy, biologics, and oral JAK inhibitors. That makes it important to know whether antihistamines add important benefit or mostly add treatment burden and harm,” says senior author Derek Chu, associate professor with McMaster’s Department of Medicine, Canadian Institutes of Health Research Chair in Allergy, and Lead of Canada’s Allergy Clinical Trials Network.

The review looked at two categories of medications: modern, second-generation antihistamines and older, first-generation antihistamines. The study found that second-generation medications – commonly known under brand names such as Reactine, Claritin, Aerius, Allegra, Rupall, and Blexten – produced small changes in eczema severity and itch, but that relief fell short of what patients and their clinicians would consider as an important improvement.

First-generation antihistamines – commonly found under brand names such as Benadryl, Chlor-Tripolon and Polaramine – produced no noticeable improvement. These older medications, however, likely increase cognitive impairment, such as drowsiness, confusion, slowed thinking, or impaired school or work performance. Such impairments are increasingly recognized to last into the days after use. Among newer second-generation antihistamines, cognitive effects were much lower and differed by drug (bilastine, desloratadine, and fexofenadine being least sedating).

“The findings support moving away from routine antihistamine use in atopic dermatitis care and toward treatments that are more effective, less likely to cause harm, and are more certain to control eczema inflammation. This may also help keep eczema control as simple and straightforward as possible, with patients focusing on high-value treatments,” says Chu, who holds a joint appointment with McMaster’s Department of Health Research Methods, Evidence and Impact.

Researchers stress that oral antihistamines have a place in treating allergic conditions such as hay fever, seasonal allergies and hives.

The work was commissioned by the American Academy of Allergy, Asthma & Immunology and the American College of Allergy, Asthma and Immunology through the Joint Task Force on Practice Parameters for the living atopic dermatitis guidelines.

The study used the McMaster-developed grading of recommendations assessment, development and evaluation (GRADE), a leading global system for rating the certainty of evidence and translating evidence into clinical recommendations.

Aspects of the study were conducted with The Research Institute of St. Joe's Hamilton.

This McMaster-led research involved partners from Harvard T.H. Chan School of Public Health, Children's Hospital of Philadelphia/University of Pennsylvania, Boston Children's Hospital, National Jewish Health/University of Colorado, UMass Chan Medical School, Arizona State University, George Washington University, Northwestern University, University of Saskatchewan, Icahn School of Medicine at Mount Sinai, University of Rochester, University of Florida, Children's Hospital Los Angeles/USC, Lakehead University, and Tufts University.

People with lived experience and advocacy partners including the Asthma and Allergy Foundation of America, Global Parents for Eczema Research, National Eczema Association, and Allergy & Asthma Network were also involved.