Category: Ageing

Are Meat Eaters Really More Likely to Live to 100 than Non‑meat Eaters, as a Recent Study Suggests?

Photo by Jose Ignacio Pompe on Unsplash

Chloe Casey, Bournemouth University

People who don’t eat meat may be less likely than meat eaters to reach the age of 100, according to a recent study. But before you reconsider your plant-based diet, there’s more to these findings than meets the eye.

The research tracked over 5,000 Chinese adults aged 80 and older who participated in the Chinese Longitudinal Healthy Longevity Survey, a nationally representative study that began in 1998. By 2018, those following diets that don’t contain meat were less likely to become centenarians compared with meat eaters.

On the surface, this appears to contradict decades of research showing that plant-based diets are good for your health. Vegetarian diets, for example, have been consistently linked to lower risks of heart disease and stroke, type 2 diabetes and obesity. These benefits come partly from higher fibre intake and lower saturated fat consumption.

So what’s going on? Before drawing any firm conclusions, there are several important factors to consider.

Your body’s needs change as you age

This study focused on adults aged 80 and older, whose nutritional needs differ markedly from those of younger people. As we age, physiological changes alter both how much we eat and what nutrients we need. Energy expenditure drops, while muscle mass, bone density and appetite often decline. These shifts increase the risk of malnutrition and frailty.

Most evidence for the health benefits of diets that exclude meat comes from studies of younger adults rather than frail older populations. Some research suggests older non-meat eaters face a higher risk of fractures due to lower calcium and protein intake.

In later life, nutritional priorities shift. Rather than focusing on preventing long-term diseases, the goal becomes maintaining muscle mass, preventing weight loss and ensuring every mouthful delivers plenty of nutrients.

The study’s findings may, therefore, reflect the nutritional challenges of advanced age, rather than any inherent problems with plant-based diets. Crucially, this doesn’t diminish the well-established health benefits of these diets for younger and healthier adults.

Maintaining muscle mass in older age is important, and that requires protein. Photo by Barbara Olsen on Pexels

Here’s a crucial detail: the lower likelihood of reaching 100 among non-meat eaters was only observed in underweight participants. No such association was found in older adults of healthy weight.

Being underweight in older age is already strongly linked with increased risks of frailty and death. Body weight therefore appears to be a key factor in explaining these findings.

It’s also worth remembering that this was an observational study, meaning it shows associations rather than cause and effect. Just because two things occur together doesn’t mean one causes the other.

The findings also align with the so-called “obesity paradox” in ageing, where a slightly higher body weight is often linked to better survival in later life.

Notably, the reduced likelihood of reaching 100 observed among non-meat eaters was not evident in those who included fish, dairy or eggs in their diets. These foods provide nutrients that are essential for maintaining muscle and bone health, including high-quality protein, vitamin B12, calcium and vitamin D.

Older adults following these diets were just as likely to live to 100 as meat eaters. The researchers suggested that including modest amounts of animal-source foods may help prevent undernutrition and loss of lean muscle mass in very old age, compared with strictly plant-based diets.

What this means for healthy ageing

Rather than focusing on whether one diet is universally better than another, the key message is that nutrition should be tailored to your stage of life. Energy needs decline with age (due to decreased resting energy expenditure), but some nutrient requirements increase.

Older adults still require adequate protein, vitamin B12, calcium and vitamin D – especially to preserve muscle mass and prevent frailty. In older adulthood, preventing malnutrition and weight loss often becomes more important than long-term chronic disease prevention.

Plant-based diets can still be healthy choices, but they may require careful planning and, in some cases, supplementation to ensure nutritional adequacy, particularly in later life.

The bottom line is that our nutritional needs at 90 may look very different from those at 50, and dietary advice should reflect these changes across the lifespan. What works for you now might need adjusting as you age – and that’s perfectly normal.

Chloe Casey, Lecturer in Nutrition and Behaviour, Bournemouth University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Popular GLP-1 Drug May Slow Down Biological Aging

By calming inflammation and reducing excess fat, semaglutide may postpone several molecular signs of aging, pointing to the potential of GLP‑1 receptor agonists to help prevent age‑related diseases.

Photo by Haberdoedas on Unsplash

Semaglutide slowed biological aging across multiple epigenetic clocks in a randomised, double-blind, placebo-controlled clinical trial. The strongest signals were seen in epigenetic measures linked to inflammation, brain, heart, blood, kidney, liver and metabolic health, suggesting that the drug may influence aging-related biology across multiple body systems. The findings offer early clinical evidence that GLP-1 receptor agonists may influence aging biology.

Glucagon-like peptide-1 (GLP-1) receptor agonist medications have gained widespread attention for effectively treating obesity, lowering blood sugar and decreasing the risk of cardiovascular disease. Some researchers have proposed that these drugs may also influence the biology of aging, but direct evidence in humans has remained limited. Now, a new study provides the first randomised, placebo-controlled clinical evidence that semaglutide, a widely used GLP-1 drug, slows down the accumulation of biological aging markers in the DNA of adults with HIV. The study is published in Nature Communications.

Researchers at the University of California San Diego and several partner institutions analysed data from a previously published clinical trial of 108 adults with HIV‑associated lipohypertrophy, a condition in which excess fat builds up around the abdomen. About half of the participants received weekly injections of semaglutide, with the rest receiving placebo injections.

The team used a set of biological “epigenetic clocks” to track cellular aging over the 32-week treatment period. These clocks detect DNA methylation, chemical marks on DNA that help regulate how genes are turned on or off without changing the genetic sequence itself. By measuring changes in these marks, the team could assess whether the treatment was associated with a slower or faster biological aging pattern.

People with HIV often experience accelerated aging, even if it is well-controlled with antiretroviral therapy, according to first author Michael Corley, PhD, associate professor at UC San Diego School of Medicine and the Stein Institute for Research on Aging. However, the study found compared to the placebo group:

  • Participants treated with semaglutide exhibited a broad pattern of slower biological aging across epigenetic clocks linked to inflammation and blood, brain, heart, kidney, liver and metabolic health.
  • The drug slowed the pace of biological aging by 9 %, as measured by the DunedinPACE epigenetic clock.
  • The drug significantly slowed biological processes associated with the risk of all‑cause mortality and age-related disease, as measured by the PCGrimAge epigenetic clock.

Research suggests there are several mechanisms by which semaglutide may influence biological aging. By reducing inflammation and metabolic stress, GLP-1 drugs decreased chronic immune activation, a primary driver of accelerated aging in people with HIV. They also reduce visceral and ectopic fat that accumulates around the abdomen and organs, which may help curb the inflammatory and metabolic signals that promote aging.

“Emerging data also suggest that GLP-1 drugs may reprogram certain cells in different organs, which could help explain why we see effects across multiple aging clocks,” said Corley.

While the study focused on people with HIV‑associated lipohypertrophy, Corley says it may also offer lessons for the wider population.

“Many of the biological processes we study in HIV are also central to aging in the general population,” he said. “Because these processes can emerge earlier or be more pronounced in people with HIV, this community can help us identify interventions that may improve healthspan more broadly.”

In a related pilot study published in npj Aging, Corley and another team of researchers found that taking semaglutide for 24 weeks:

  • Reduced the rate of biological aging for 42% of participants with HIV and metabolic dysfunction-associated steatotic liver disease (MASLD) as measured by the DunedinPACE epigenetic clock. Those participants also had a greater reduction in liver fat compared with participants whose pace of aging sped up.
  • Slowed aging associated with the risk of all‑cause mortality in 34% of participants as measured by the PCGrimAge epigenetic clock.
  • Increased the length of telomeres in nearly 49 % of participants as measured by the PCDNAmTL epigenetic clock. Those participants also tended to walk faster after treatment, suggesting better physical function.

Together, these studies add to growing evidence that GLP-1 drugs may influence pathways involved in biological aging.

“We are not saying that semaglutide reverses aging or makes people younger. What we are seeing is a signal that it may slow some of the biological processes associated with aging.”

— Michael Corley, PhD

“We are not saying that semaglutide reverses aging or makes people younger,” said Corley. “What we are seeing is a signal that it may slow some of the biological processes associated with aging. With newer GLP-1–based therapies now emerging, the field has an opportunity to test whether different drugs in this class have distinct effects on aging biology and to identify which patients may benefit most.”

Larger clinical trials are needed to confirm the findings, determine how long treatment effects last, and establish optimal dosing and treatment duration for both people with HIV and the broader population. Future studies will also be needed to test whether the effects of GLP-1 effects on aging biology are enhanced when combined with lifestyle interventions such as diet, exercise and sleep optimization.

The Stein Institute for Research on Aging plans to translate these results into individualized “aging dashboards” to track biological aging with epigenetic clocks, enabling clinicians to design personalised therapies that target the underlying mechanisms of aging and help prevent age‑related diseases.

By Susanne Clara Bard

Source: University of California San Diego

Research Finds Best Exercise Type to Preserve Muscle in Seniors

By Julie Schomberg

Photo by Barbara Olsen on Pexels

High intensity interval training (HIIT) may be the optimal exercise for reducing body fat while maintaining muscle mass in older adults, according to new research led by Australian academics.

“We found that high, medium and low intensity exercises all led to modest fat loss but only HIIT retained lean muscle,” said lead author and exercise physiologist Dr Grace Rose of the University of the Sunshine Coast.

The study examined how the intensity of different exercises could influence body composition in healthy older adults.

“While moderate training reduced fat mass, it also caused a small decline in lean muscle,” she said. “Both high and moderate intensities improved the composition of weight carried around the middle. Further analysis is needed of the low intensity results.” Dr Rose said the findings were particularly useful because body composition was implicated in the progression of many chronic diseases as people aged.

More than 120 healthy older adults from the Greater Brisbane region participated in the study, completing three exercise sessions a week in the gym for six months. 

Their average age was 72 years old and average body mass index was 26kg/m2, categorised as normal for people aged over 65.

UniSC Associate Professor of Physiology and co-author Mia Schaumberg welcomed the the paper published in the journal Maturitas, with collaborators including UniSC’s Healthy Ageing Research Cluster and The University of Queensland.

“High intensity training in this study involved repeated short bursts, or intervals, of very hard exercise – where breathing is heavy and conversation is difficult – alternated with easier recovery periods. More than 120 healthy older adults from the Greater Brisbane region participated in the study, completing three exercise sessions a week in the gym for six months. 

Their average age was 72 years old and average body mass index was 26kg/m2, categorised as normal for people aged over 65.

UniSC Associate Professor of Physiology and co-author Mia Schaumberg welcomed the timing of the paper published in the journal Maturitas, with collaborators including UniSC’s Healthy Ageing Research Cluster and The University of Queensland.

“High intensity training in this study involved repeated short bursts, or intervals, of very hard exercise – where breathing is heavy and conversation is difficult – alternated with easier recovery periods,” she said.

“HIIT likely works better because it puts more stress on the muscles, giving the body a stronger signal to keep muscle tissue rather than lose it.”

Source: University of the Sunshine Coast

‘Wait and See’: Three Words Costing Postmenopausal Women Their Hair

More than half of postmenopausal women have clinically measurable hair loss. The most common response is to tell them to do nothing

Photo by Kateryna Hliznitsova on Unsplash

52% of postmenopausal women experience female-pattern hair loss, according to peer-reviewed research published in Menopause, the journal of the North American Menopause Society. Hot flushes – one of the symptoms that owns many public conversations about menopause – affect a larger proportion of women, but the disparity is not in the data. It is in how medicine responds to them. At more than one in two women, female-pattern hair loss is routinely absent from clinical consultations, rarely investigated at first presentation, and almost universally met with the same advice: give it time.

Why timing matters

During and after menopause, declining oestrogen levels and shifts in androgen balance cause susceptible hair follicles to gradually shrink. Each hair grows finer and shorter, with a briefer growth period per cycle. Left long enough without intervention, some follicles reach a point of no return, and the damage becomes irreversible.

“When we say irreversible, we mean that the follicle has become so damaged or inactive that it can no longer reliably regenerate a healthy terminal hair on its own,” says Dr Kashmal Kalan, Medical Director at Alvi Armani South Africa. “Medical therapies may help stabilise surrounding hair at that stage, but they may not recover what has already been lost,” says Dr Kalan.

For many women, that window closes not because they made an informed decision, but because nobody told them they had options. The advice they received – that gradual thinning is normal, that stress is a likely factor, that it may settle with time – sounded measured.

The cost of being dismissed

When the condition is classified as cosmetic, clinical urgency disappears. The patient is reassured rather than assessed, even though menopausal thinning is frequently a visible signal of systemic change. Hormonal shifts, nutritional deficiencies, thyroid dysfunction, and inflammatory or metabolic factors are all documented contributors, and none of them are cosmetic.

The consequences reach well beyond the scalp. Research published in the British Journal of Dermatology found that over 60% of women with hair loss actively avoided social interactions because of it. A separate study in the Journal of Cosmetic Dermatology found that affected women reported significantly higher social anxiety, lower self-esteem, and reduced life satisfaction compared to men experiencing the same condition. What begins on the scalp moves into how a woman presents professionally, how she engages socially, and how she sees herself.

A clinical framework built for men, applied to women

The protocols widely used to assess and treat this condition were largely developed around male patients. Defined hairline recession, concentrated donor areas, and linear progression are all considered male presentations. As a result, women have largely been assessed within a framework built for someone else.

“Applying male-based protocols to women can absolutely compromise outcomes. Female hair restoration requires an understanding of female-specific patterns of loss, progression risk, and the long-term hormonal picture. Preservation of softness, natural density gradients, and age-appropriate framing are considerations with no real equivalent in the male framework. In experienced hands, those distinctions are built into every stage of assessment and planning – not treated as secondary.”

What rigorous care looks like

At Alvi Armani, the first step is not a treatment recommendation – it is a diagnosis. A comprehensive workup, including blood investigations, is conducted before any intervention is discussed, because in menopausal women the drivers are rarely singular and what is visible on the scalp is seldom the whole picture.

“Not every patient is an immediate candidate for surgical restoration and recognising this is itself part of responsible practice. Medical stabilisation, non-surgical therapies, and hormonal management in collaboration with relevant specialists all form part of the treatment landscape – guided by individual diagnosis, not assumption,” Dr Kalan concludes.

“If any of this sounds familiar – the gradual changes, the concerns dismissed, the years of quietly adapting – it is worth knowing that the window is not necessarily closed. But it is also not standing still. Hair loss during menopause is extremely common – but common does not mean insignificant, and it does not mean inevitable.”

Genetic Trade-off Between Youth and Longevity Uncovered by Researchers

A 3-month-old African turquoise killifish, left, and a 5-month-old killifish, right, show aging much like that in humans.

Researchers have identified a gene that directly links early-life growth and reproductive success with accelerated ageing and increased cancer risk later in life, offering new insight into a longstanding theory in evolutionary biology.

Now, an international team of researchers provides experimental evidence for the theory of antagonistic pleiotropy, the idea that certain genes can provide advantages early in life while contributing to disease and decline in old age.

What’s fascinating – and slightly terrifying – is that the cancer we see in these fish isn’t a random accident. It’s the direct shadow of their youthful vitality

Prof Itamar Harel

While widely accepted in theory, scientists have struggled to identify specific genes responsible for such trade-offs in vertebrates. Using the African turquoise killifish, a short-lived species recently pioneered by Harel and colleagues for genetic ageing research, the team focused on the gene vgll3, which has been previously linked to the timing of human puberty and maturation in other species, particularly Atlantic salmon.

By modifying this gene using CRISPR technology, the researchers observed clear effects. Fish with altered vgll3 grew faster and reached sexual maturity earlier, traits that could offer a reproductive advantage in natural environments.

However, these benefits came with significant long-term costs. The same fish showed reduced lifespans and a higher incidence of age-related tumours, including melanoma-like cancers.

“We have effectively caught evolution in the act of making a trade-off. For years, we’ve asked why our bodies can’t just maintain themselves indefinitely. This gene gives us a direct answer: nature doesn’t prioritise longevity; it prioritises continuity. We are built to sprint, not to marathon,” said Prof Itamar Harel at Hebrew University.

Further analysis showed that the gene influences key biological processes, including cell division, stem cell activity, and DNA repair. Increased cellular activity may help explain both the rapid development observed in younger fish and the accumulation of damage that leads to disease in older individuals.

The researchers also developed a new immunodeficient killifish model, enabling them to transplant and study tumour cells in ways not previously possible in this system.

“What’s fascinating – and slightly terrifying – is that the cancer we see in these fish isn’t a random accident. It’s the direct shadow of their youthful vitality. The same machinery that drives a cell to build a young body is hijacking the system to build a tumour in the old one. If we can understand this mechanism, we might finally learn how to decouple healthy growth from the disease of ageing,” Dr Harel added.

Because vgll3 is conserved in humans, the findings may have broader implications for understanding human development, ageing, and age-related diseases. While previous association studies have linked the gene to puberty timing and hormone levels, functional data were missing until now.

The discovery could contribute to future efforts in cancer prevention and research aimed at extending healthy lifespan. Researchers say the next step will be to explore whether it is possible to separate the gene’s beneficial early-life effects from its harmful consequences later in life.

Source: EurekAlert!

Calcium and Vitamin D Supplements Offer Little to No Meaningful Benefit on Fracture and Fall Prevention

Recommendations for calcium and vitamin D supplementation should be re-evaluated, suggest researchers

Photo by Kampus Production

Calcium, vitamin D, or combined supplements offer little to no clinically meaningful benefit on fracture and fall prevention in most older people, finds an in-depth review of the latest evidence published by The BMJ.

Almost a third of people aged 65 and older fall each year, often resulting in fractures, which are linked to pain, reduced quality of life, and the need for residential care. Preventing falls and fractures is therefore a global public health priority.

Several previous evidence reviews have found no reduction in fractures with either calcium or vitamin D supplements and results are inconsistent for combined use. The benefit of vitamin D on falls also remains unclear.

Yet despite this, many clinicians, guidelines, and regulatory agencies recommend vitamin D supplements (with or without calcium) for bone health, and prescriptions have increased substantially in recent years.

To address this uncertainty, researchers in Canada reviewed the results of 69 randomised controlled trials involving 153,902 adults that assessed the effect of calcium or vitamin D supplements – or a combination of both – on reducing the number of fractures and falls compared with placebo or no treatment.

The trials were of varying quality, but the researchers were able to assess their risk of bias and certainty of evidence using established tools.

After agreeing on clinically meaningful thresholds, the researchers found little to no effect for experiencing any fracture from use of calcium supplements (moderate certainty evidence from 11 trials; 9,067 participants), vitamin D supplements (high certainty evidence from 36 trials; 92 045 participants), or combined supplementation (high certainty evidence from 15 trials; 51 126 participants).

Calcium, vitamin D, or combined supplementation also appeared to have little to no effect on specific fractures, such as hip fractures, or falls, based largely on moderate to high certainty of evidence.

The researchers acknowledge that some analyses included a small number of trials and participants, so these findings should be interpreted with caution, and results may not apply to individuals with specific bone disorders or to those receiving drug treatment for osteoporosis.

However, the findings were consistent after further analyses to account for differences such as participant age, sex, history of fractures and falls, and average dietary calcium intake, supporting the strength of their conclusions.

As such, they say these findings “do not support routine supplementation with calcium or vitamin D, or combined supplementation to prevent fractures and falls” and they suggest clinicians, guideline panels, and regulatory agencies “should re-evaluate their general recommendations for calcium and vitamin D supplementation in light of current evidence.”

Evidence from rigorous and well-powered trials is needed to inform recommendations for supplementation in higher-risk groups, say researchers in a linked editorial.

In the meantime, they suggest that focus and funding should be redirected towards interventions that have been shown to offer meaningful prevention of falls and falls related injuries, such as balance and resistance exercise, and interventions that combine elements like exercise, hazard assessment or education, tailored to individual risk.

Source: The BMJ Group

Choosing Safer Diabetes Medications for Older Adults

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Older adults with type 2 diabetes face a difficult trade-off: they are among the most vulnerable to medication-related harms yet are often underrepresented in the clinical trials that guide treatment decisions. A new study led by Yuan Lu, ScD, helps address this gap by providing large-scale, real-world evidence about the safety of commonly used diabetes medications.

Published in Nature Communications, the study analysed data from more than 1.8 million people aged 65 and older across the United States and Europe. The researchers compared four major classes of second-line antihyperglycaemic medications – typically prescribed when first-line therapy such as metformin is not sufficient – across 18 safety outcomes.

“Evidence from clinical trials often does not fully capture older adults,” says Lu, assistant professor of medicine (cardiovascular medicine) at Yale School of Medicine. “They are more likely to experience side effects due to frailty, multiple chronic conditions, and the use of several medications at the same time.”

Newer diabetes drugs show overall safety advantages

The study found a consistent pattern: newer classes of medications, including GLP-1 receptor agonists and SGLT2 inhibitors, were generally associated with lower risks of several important adverse outcomes compared to older drugs such as sulfonylureas and DPP-4 inhibitors.

Newer agents were linked to lower risks of hypoglycaemia, hyperkalaemia, and peripheral oedema – complications that can be especially dangerous in older adults. However, the findings also highlight important trade-offs. For example, SGLT2 inhibitors were associated with a higher risk of diabetic ketoacidosis, while GLP-1 receptor agonists were more likely to cause gastrointestinal side effects such as nausea and vomiting.

Rather than identifying a single “best” medication, Lu emphasises that the results support more informed, individualised decision-making. “Some patients may have a higher risk of hypoglycaemia, while others may be more susceptible to diabetic ketoacidosis,” she says. “These risks need to be considered together as part of an individual patient profile.”

Real-world data at a global scale

A key strength of the study is its scale and approach. The analysis drew on nine large databases and was conducted through the Observational Health Data Sciences and Informatics (OHDSI), an international research network that enables standardized analyses across diverse health care systems.

By using harmonised real-world data and consistent analytic methods, the researchers were able to evaluate a broad range of safety outcomes in routine clinical practice – offering insights that complement and extend findings from randomised trials.

Supporting safer prescribing for an aging population

As the population ages and the use of newer diabetes medications continues to grow, understanding their safety profiles in older adults is increasingly important. The findings reinforce current guideline recommendations that often favour newer agents, while also underscoring the need to tailor treatment decisions to each patient’s risks and preferences.

Like all observational studies, the analysis cannot fully rule out unmeasured differences between patients. Still, the large, multinational design gives a more complete picture of medication safety in a population often underrepresented in clinical research.

Looking ahead, Lu and her colleagues hope to expand this work to examine the comparative safety of individual medications and to evaluate the safety of newer GLP-1 receptor agonists across a wider range of outcomes, including among people with obesity. “By providing more evidence in populations that clinicians see every day, our goal is to support safer, more informed care,” she says.

Source: Yale School of Medicine

HEPA Air Purifiers May Boost Brain Power in Adults Over 40 – New Research

Photo by Mari Lezhava on Unsplash

Nicholas Pellegrino, University of Connecticut; Doug Brugge, University of Connecticut, and Misha Eliasziw, Tufts University

Using an in-home HEPA purifier for one month spurs a small but significant improvement in brain function in adults age 40 and older. That’s the result of a new study we co-authored in the journal Scientific Reports.

HEPA purifiers – HEPA stands for high efficiency particulate air – remove particulate matter from the air. Exposure to particulate matter has been connected to respiratory and cardiovascular illnesses as well as neurological diseases such as Alzheimer’s and Parkinson’s. Environmental health researchers increasingly recommend that people use HEPA air purifiers in their homes to lower their exposure to particulate matter, but few studies have examined whether using them boosts mental function.

We analysed data from a study of 119 people ages 30 to 74 living in Somerville, Massachusetts. Somerville sits along Interstate 93 and Route 28, two major highways, resulting in relatively high levels of traffic-related air pollution. This makes it an especially good location for testing the health effects of air purifiers.

We randomly assigned participants to one of two groups. One used a HEPA air purifier for one month and then a sham air purifier – which looked and acted like the real thing but did not contain the air-cleaning filter – for one month, with a monthlong break in between. The second group used the real and sham purifiers in reverse order.

After each month, participants took a test that measured different aspects of their mental capacity. The test probed people’s visual memory and motor speed skills by measuring how quickly they could draw lines between sequential numbers, and it tested executive function and mental flexibility by asking them to draw lines between alternating sequential numbers and letters.

We found that participants 40 years and older – about 42% of our sample – on average completed the section testing for mental flexibility and executive function 12% faster after using the HEPA purifier than after using the sham purifier. That was true even when we accounted for factors like differences in the amount of time participants spent indoors, with either filter, as well as how stressful they found the test.

This improvement may seem small, but it is similar to the cognitive benefits that people experience from increasing their daily exercise. While you may not experience a sudden increase in clarity from a 12% boost, preventing cognitive decline is vital for long-term well-being. Even small decreases in cognitive functioning may be associated with a higher risk of death.

Studies increasingly show that air pollution can be detrimental to brain health.

Why it matters

Air pollution can negatively affect mental function after just a few hours of exposure. Studies show that air purifiers are effective at reducing particulates, but it’s unclear whether these reductions can prevent cognitive harm from ongoing pollution sources like traffic. Research has been especially lacking in people living near major sources of air pollution, such as highways.

People living near highways or major roadways are exposed to more air pollution and also experience higher rates of air pollution-related diseases. These risks aren’t encountered by all Americans equally: People of color and low-income people are more likely to live near highways or areas with heavy traffic.

Our study shows that HEPA air purifiers may offer meaningful health benefits under these circumstances.

What still isn’t known

Research shows that air pollution begins to affect cognitive function especially strongly around age 40. These effects may become increasingly prominent as people age.

HEPA air purifiers may therefore be especially beneficial for older adults. Our study did not explore this possibility, as fewer than 10 of our 119 participants were over the age of 60.

Also, our participants only used a HEPA air purifier for one month. It’s possible that longer durations of air purification may sustain or even increase the improvement in cognitive function we observed in our study.

Finally, it is unclear exactly how air purifiers improve cognition. Some studies suggest that exposure to particulate matter reduces the amount of the brain’s white matter, which helps brain cells conduct electrical signals and maintains connections between brain regions. The brain regions most harmed by air pollution are the ones that control mental flexibility and executive function, the same domains in which we saw improvements in our study.

We plan to study whether reducing particulate matter by using air purifiers is indeed protecting the brain’s white matter, and whether it could reverse some cognitive decline. We will explore that possibility by studying how levels of molecules called metabolites, which cells produce as they do their jobs, change in response to breathing polluted air and air cleaned by a HEPA filter.

The Research Brief is a short take on interesting academic work.

Nicholas Pellegrino, Research Associate in Public Health Sciences, University of Connecticut; Doug Brugge, Professor of Public Health Science and Community Medicine, University of Connecticut, and Misha Eliasziw, Associate Professor of Biostatistics, Public Health and Community Medicine, Tufts University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Alzheimer’s Risk Gene APOE4 Silently Undermines Bone Quality in Women

Buck Institute researchers discover a surprising connection between a major risk factor for Alzheimer’s

Photo by Karolina Grabowska on Pexels

Scientists at the Buck Institute for Research on Aging, along with collaborators at UC San Francisco, have discovered that APOE4, the most common genetic risk factor for Alzheimer’s disease, causes bone quality deficits specifically in female mice, through a mechanism that is invisible to standard imaging and can emerge as early as midlife.

The findings, published in Advanced Science, reveal an unexpected biological link between Alzheimer’s risk and skeletal health, and identify a new molecular pathway that could one day inform earlier diagnosis of cognitive decline or guide treatment for bone quality loss in women who carry the APOE4 gene.

“What makes this finding so striking is that bone quality is being compromised at a molecular level that a standard bone scan simply will not catch,” says Buck professor Birgit Schilling, PhD, a senior author of the study. “APOE4 is quietly disrupting the very cells responsible for keeping bone strong, and it is doing this specifically in females, which mirrors what we see with Alzheimer’s disease risk.”

Physicians have long observed that people with Alzheimer’s disease suffer bone fractures at higher rates, and that a diagnosis of osteoporosis in women is actually the earliest known predictor for Alzheimer’s. But the underlying mechanism connecting brain and bone health has remained elusive.

To investigate this connection, researchers, led by research scientist and co-first author of the paper Charles Schurman, PhD, first performed a proteomic analysis of aged mouse bone, a comprehensive survey of all the proteins present in the tissue. “The team discovered that bone, and particularly osteocytes, the long-lived cells embedded within it, is unusually rich in proteins associated with neurological disease, including apolipoprotein E [APOE] and amyloid precursor protein,” says Schurman. “Notably, APOE expression in osteocytes was twice as high in aged female mice as in young or male mice.”

The team then turned to a humanised mouse model carrying either APOE2 (associated with reduced Alzheimer’s risk), APOE3 (considered neutral), or APOE4 (the risk variant), and analysed bone and hippocampal tissue from the same animals. APOE4 produced strong, sex-specific effects on both the bone transcriptome and proteome; researchers found the protein-level disruption in bone was actually more pronounced than the corresponding changes in the hippocampus.

Despite the protein level disruption, cortical bone structure appeared normal under imaging. Researchers found that bone quality deficits arose not from changes in bone shape or density, but from APOE4’s suppression of perilacunar/canalicular remodelling, the process by which osteocytes actively maintain the microscopic channels that keep bone mechanically resilient. When this maintenance breaks down, bone quality deteriorates even when it looks intact.

“These results suggest that osteocytes could serve as early biological sentinels for age-related cognitive decline in women carrying APOE4,” says professor Lisa Ellerby, PhD, also a senior author of the paper. The Ellerby lab studies genetic risk factors for Alzheimer’s.  “We think that targeting osteocyte function may open a new front in preserving bone quality in this population.”

Researchers say there is a larger takeaway from this research that links brain and bone science.  “While we think this work is relevant for human patients with Alzheimer’s disease or with osteoporosis, this study also highlights the need for researchers to consider the human body as an entire system without isolating organs and diseases from each other,” says Ellerby.

Source: Buck Institute for Research on Aging

Physical Activity and Appropriate Sleep Linked to Subsequent Lower Dementia Risk

Meta-analysis including millions of middle-aged to older adults supports recommended activity and sleep duration to reduce dementia risk

Photo by Barbara Olsen on Pexels

Regular physical activity and getting the recommended amount of sleep may reduce dementia risk later in life, according to a new study by Akinkunle Oye-Somefun and colleagues of York University, Canada, published April 8, 2026 in the open-access journal PLOS One.

An estimated 55 million people live with dementia worldwide, and both its prevalence and cost are expected to increase, with global costs projected to reach $2 trillion dollars by 2030. Current treatments for preventing or treating dementia have limited efficacy; therefore, public health efforts have also aimed at healthy lifestyle factors to reduce the risk of dementia before symptoms occur. Healthy behaviours such as regular physical activity and good sleep hygiene are known to support cognitive health; however, there remains a need to better understand their relationship to dementia.

In this systematic review and meta-analysis, researchers analysed data from 69 prospective cohort studies representing millions of community-dwelling adults aged 35+, to see if there was a link between the development of dementia and three lifestyle behaviours: physical activity, sedentary behaviour, and sleep duration. Each of the observational studies recorded behaviours of cognitively healthy participants, then followed up at a later timepoint to report subsequent rates of dementia.

Overall, the meta-analysis found that regular physical activity, less sedentary time, and appropriate nightly sleep (7–8 h) were associated with a lower subsequent risk of dementia. Regular physical activity was associated with an average 25% lower risk of dementia among the 49 studies analysed; however, the researchers note that there was considerable heterogeneity between the studies.

Too little sleep (< 7 h) or too much sleep (> 8 h) was associated with an 18% and 28% higher subsequent risk of dementia, respectively, compared to optimal nightly sleep of 7–8 hours, though there was again considerable heterogeneity among the 17 studies analysed. Prolonged sitting (> 8 hours per day) was associated with a 27% higher risk of dementia among the three relevant studies analysed.

The study is consistent with and expands on previous research, using a large, diverse population with long follow-up times. While the study design cannot show any causative link between physical activity, sleep and dementia, the findings suggest an association between adherence to recommended physical activity and sleep levels in middle- and older-age adults and lowered dementia risk later in life.

The authors add: “Dementia develops over decades, and our findings suggest that everyday behaviours such as physical activity, time spent sitting, and sleep duration may be linked to dementia risk. Understanding how each of these behaviours relates to risk over time may help researchers identify opportunities to support brain health across the life course.”

“Separately, one aspect I personally found most interesting while conducting the study was the relatively limited evidence base on sedentary behaviour. Despite growing recognition that prolonged sitting is distinct from physical inactivity, we found only a small number of cohort studies examining its relationship with dementia risk. This highlights an important gap for future research.”

Provided by PLOS