These three common sleep habits tied to signs of brain aging

 How we sleep may have lasting impacts for our brain health as we age. A new University of Arizona study has found that several common sleep behaviors may be linked to signs of brain aging. 

The study, published in the journal Alzheimer's & Dementia, used existing brain scans and questionnaire responses from more than 23,000 middle-aged and older adults from a large biomedical database. The work is part of a broader collaborative project between the U of A Department of Psychology, the Zuckerman College of Public Health and the University of Southern California. 

The researchers identified three sleep behaviors distinctly associated with a marker of brain aging in healthy people: sleeping outside the recommended seven-to-nine-hour range, frequent daytime napping and sleeplessness. All three were linked to greater volume of white matter lesions, areas of damage in the brain that can accumulate with age and are tied to a higher risk of dementia, including Alzheimer's disease. 

Madeline Ally, the study's lead author and a graduate researcher at the Department of Psychology, said that sleep is often studied as one overall measure rather than a collection of distinct patterns and habits, which can obscure how sleep relates to brain aging. 

"Sleep is a universal but complex behavior, and there is still much to learn about how different aspects of sleep relate to brain health," Ally said. 

For the study, participants completed a baseline questionnaire from 2006 to 2010 on five sleep behaviors: sleep duration, daytime napping, sleeplessness, unintentional daytime dozing and snoring. About nine years later, the same participants underwent brain MRI scans, which the researchers used to measure white matter lesion volumes. The study was conducted in collaboration with David Raichlen, the lead collaborator at the University of Southern California, and a professor of human and evolutionary biology. 

All five behaviors were initially associated with greater lesion volume. But after the researchers accounted for related blood vessel health and lifestyle factors that can also affect the brain, such as high blood pressure, smoking and physical inactivity, three behaviors continued to stand out: sleeping outside the recommended range, frequent daytime napping and greater sleeplessness. Snoring and unintentional daytime dozing did not.

The findings on daytime napping were particularly interesting, since research shows short naps may also be helpful for alertness and cognition. Gene Alexander, the study's senior author and a professor in the Department of Psychology, said that the questionnaire did not capture details on the length or timing of individual naps. Future work will need to test whether shorter, occasional naps have different effects on the brain over time compared to longer, more frequent ones.

In a follow-up analysis, the researchers took a closer look at sleep duration and found that participants sleeping fewer than seven hours per night had increased lesion volume compared to those sleeping within the recommended range.

"Our findings suggest that having too little sleep may lead to greater white matter lesion volumes in the brain as we age," said Alexander. "We didn't see greater white matter impacts in people who reported longer sleep durations, but this needs to be followed up in cohorts with more long sleepers."

Nevertheless, Alexander said the three behaviors share a feature that makes them particularly important to study: each can be changed. 

"Sleep is one of those potentially modifiable risk factors. If we can improve the quality of our sleep, it may help reduce the impacts of brain aging and maybe even lower the risk for dementias like Alzheimer's disease," Alexander said. 

Remote work has increased isolation, with impacts on mental health

Summary author: Meagan Phelan

Peer-Reviewed Publication

American Association for the Advancement of Science (AAAS)

FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmail

The rise in remote work caused by the COVID-19 pandemic has substantially increased time spent alone and worsened workers’ mental health, according to a new study based on survey data from more than 500,000 Americans. In evaluating remote employees’ mental health, the analysis moves beyond the main consequence of remote work more typically evaluated in studies to date: worker productivity. The study’s results suggest that “the shift in work location to the home carries measurable costs at the population level,” Emma Zhang and Rourke O’Brien write in a related Perspective. After the pandemic led to many people working from home, the results of studies evaluating the mental health impacts on employees were mixed. To understand remote work’s effect on human well-being better, Natalia Emanuel and colleagues analyzed data from five nationally representative US-based surveys that together spanned more than a decade and included 568,000 respondents. They compared workers’ experiences before the pandemic (2011 to 2019) with experiences from the post-peak period (2022 to 2024), excluding the acute pandemic years of 2020 to 2021. The authors found that workers in jobs amenable to remote work experienced substantially larger post-pandemic increases in time spent alone, worsened mental well-being across multiple measures, and increases in the use of mental health services and prescriptions. These effects were particularly pronounced among individuals living alone. Noting a limitation of their study, the authors said, “Given that our data end in 2024, we cannot fully capture long- term adaptations among remotable workers.” If workers made changes, such as cultivating social networks outside of work, they may not yet have reaped the full benefits by the time of the study, they added. “Across a range of remote work arrangements, both individuals and organizations may want to prioritize making remote work less isolating by, for example, coordinating in-office days for hybrid workers or encouraging informal interaction, even online,” Emanuel et al. conclude.

 

Data is available for the creation of data visualization images. For more information, please contact Natalia Emanuel at natalia@nataliaemanuel.com

---

Journal

Science

DOI

10.1126/science.aec7671  

A different view of ultraprocessed foods

 Though several randomized controlled trials have investigated the effects of ultraprocessed foods (UPF) on obesity, leading to news coverage that suggests ultraprocessing is inherently harmful, the reality is different, according to the authors of this Perspective. 

Based on the design of clinical trials conducted to date, it is very difficult to attribute negative effects observed in trial participants to ultraprocessing. Instead, these effects are likely due to differences in traditional nutritional properties that UPFs frequently exhibit – including soft textures (which can lead people to eat more and faster), high calorie density, high amounts of saturated fat and salt, and low fiber and protein content. These properties affect health regardless of the extent of food processing, Faidon Magkos and colleagues say. 

The authors describe the five clinical trials conducted so far on UPFs in the USA, UK, Denmark, and Japan, outlining the trials’ methods, variable findings, and limitations. “Collectively, available randomized controlled trials provide weak support for an ultraprocessing-specific effect of UPFs on body weight regulation and cardiometabolic function that is independent of established nutritional determinants,” Magkos et al. write. 

They note that the UPF concept encompasses many foods that are unhealthy, but also foods that are not necessarily harmful and even some that are beneficial. 

Based on evidence from the trials, they recommend that policy guidance around UPFs should focus on distinguishing nutritionally poor, calorie-dense, and rapidly consumed foods – regardless of their degree of processing.

Hope for ketogenic therapy in treatment of anorexia nervosa

 

A pilot study published today in Communications Medicine demonstrates the potential of a new approach to treating anorexia nervosa — a disorder for which effective treatments have been significantly limited. The research from UC San Diego School of Medicine reports that a ketogenic nutritional intervention — a high-fat, low-carbohydrate, moderate-protein diet — was feasible and safe for patients with weight-normalized and mildly underweight anorexia nervosa. The ketogenic intervention was well-tolerated by participants, with high adherence rates and no significant weight loss observed throughout the program. Furthermore, significant improvements were observed in eating disorder symptoms, with nearly 3 in 4 of study completers in the recovered range at study end, no longer meeting criteria for an anorexia nervosa diagnosis, and all completers experiencing an improvement in depression scores. 

 

Anorexia nervosa is a devastating psychiatric disorder with among the highest mortality rate of any mental illness; in the United States, a death occurs every 52 minutes as a result of this disorder or its complications. Even after successful weight restoration, patients often struggle with persistent psychological symptoms — including body dissatisfaction, an intense fear of eating, and a preoccupation with shape — that drive an alarmingly high risk of relapse.

 

Study lead Guido Frank, MD, Professor of Psychiatry at UC San Diego School of Medicine, who has been studying and treating anorexia patients for over 25 years, launched this study to broaden treatment options for this high-risk population. “We urgently need new approaches to anorexia nervosa. Our work with ketogenic therapy looks beyond standard therapies and potentially at the underlying physiology of the disorder”, states Dr. Frank. “Growing evidence links anorexia nervosa to neurometabolic dysfunction, and we are hopeful that direct metabolic intervention can regulate neural function and address the psychological symptoms patients experience.” 

 

The outpatient, nationwide, single-arm clinical study delivered a supervised 14-week ketogenic intervention, with 18 of the 22 enrolled participants (82%) completing the study. No significant change in weight was observed throughout the program (as measured by BMI). By the end of the study, 72% of study completers reached the recovered range of eating disorder symptoms as measured by eating disorder scales (Eating Disorder Examination Questionnaire, EDE-Q, and Eating Disorder Inventory-3, EDI-3) and all showed improvements in depression scores (as measured by the Beck Depression Inventory, BDI), with 72% within normal range. 

 

For co-author Barbara Scolnick, MD, an internal medicine physician in Waban, Massachusetts, this study is the culmination of a decade-long personal journey. “The scientific inquiry that led to this research began in search of answers for my niece, Caroline Beckwith,” Dr. Scolnick shared. “Ketogenic therapy, a standard in epilepsy care, was the major catalyst, when combined with other interventions, that allowed Caroline to achieve remission after a 15-year struggle with anorexia nervosa. I am encouraged by these preliminary findings, which indicate that this treatment may provide a path forward for others like Caroline.” 

 

While the authors acknowledge the clinical sensitivities of dietary interventions in this patient population, this study builds on prior preliminary evidence to provide proof of concept. The findings indicate that, when delivered with specialized medical supervision and trained support, ketogenic therapy holds potential for those who have failed to respond to traditional treatments.

 

“This study highlights the promise of dietary interventions that target normalizing underlying neurometabolic function for even the most intractable psychiatric conditions like anorexia nervosa,” said Jan Ellison Baszucki, co-founder and president of Baszucki Group, who funded the study. “We hope this work drives awareness and support for researching and delivering ketogenic therapy for eating disorders, providing new hope for patients and their families.”

 

A current extension of this study, for patients with both anorexia nervosa and bulimia nervosa diagnoses, is underway and recruiting participants nationally. Those interested in learning more or joining the study can find more information at the study site. 

---

Journal

Communications Medicine

DOI

10.1038/s43856-026-01644-0 

It may not just be what’s in ultra-processed foods, but how they’re made

New observational study suggests processing itself could partly explain links to diabetes, heart disease, and early death

FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

"Addressing structural and policy-related barriers to accessing fresh and minimally processed foods remains critical for promoting dietary changes that improve the health and life span for all Americans,” said Dariush Mozaffarian, cardiologist and director of the Food is Medicine Institute at the Friedman School of Nutrition Science and Policy at Tufts University.

view more 

Credit: Imani Khayaam for Tufts University

Concerns about the health effects of ultra-processed foods are growing, as studies increasingly link them to conditions such as heart disease, diabetes, and even early death. But scientists are still debating what’s driving those risks: the nutritional quality of these foods—which are often high in saturated fat, sodium, and added sugars—or the industrial processing and additives used to make them. 

A new study from researchers at the Food is Medicine Institute at the Gerald J. and Dorothy R. Friedman School of Nutrition Science and Policy at Tufts University, published in American Journal of Public Health, suggests the processing itself may play an independent role. The researchers found that people who ate more ultra-processed foods had worse health outcomes, even after accounting for the overall nutritional quality of the foods. 

“The findings suggest ultra-processed-food factors beyond nutrients—such as changes to foods’ cellular structure, loss of beneficial chemical compounds, additives, and chemicals from packaging—may create health risks not addressed by traditional nutrition metrics or policies,” said the study’s senior author, Dariush Mozaffarian, cardiologist and director of the Food is Medicine Institute. 

For the observational study, the researchers analyzed data from 10 consecutive cycles of the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018, linked to National Death Index through 2018. Study participants had completed one or two 24-hour dietary recalls. 

Using a standard classification system, the team grouped foods based on how they were made—from minimally processed food-based ingredients like fruits and vegetables to ultra-processed products made with industrial ingredients and additives not typically used in cooking. The researchers also rated the nutritional quality of foods using a system that scores foods based on their overall healthfulness. Each participant received an overall diet-quality score based on the foods they reported eating. The team then examined how ultra-processed food consumption was linked to current health measures—such as weight, blood sugar, and cholesterol—as well as long-term risk of death.  

For every 10% increase in calories from ultra-processed foods, the researchers found worse health markers. People who ate more of these foods tended to have higher body weight, worse blood sugar control, higher blood pressure, and less favorable cholesterol levels. They were also more likely to have conditions such as diabetes, metabolic syndrome, and cancer and had a slightly higher risk of dying during the study period. 

These links remained even after researchers accounted for reported foods’ nutrient quality and the amounts of saturated fat, added sugar, or sodium present in the ultra-processed foods. The patterns were largely the same across different subgroups of people. 

“Ultra-processed foods make up a substantial portion of the American diet, accounting for more than 50% of adults’ and about 60% of children’s caloric intake,” said Juna Hatta-Langedyk, first author and an undergraduate biology student at Tufts. “Understanding how these foods affect health is a critical public health priority, given the large proportion of the population affected.” 

“Addressing structural and policy-related barriers to accessing fresh and minimally processed foods remains critical for promoting dietary changes that improve the health and life span for all Americans,” said Mozaffarian. “Our findings can help inform many current policy efforts, such as a national definition of ultra-processed foods, and multiple states’ endeavors to propose and pass laws addressing ultra-processed foods, including warning labels, bans on certain additives, and limits in school meals.”  

Lu Wang, Bingbing Fan, and Peilin Shi from the Friedman School of Nutrition Science and Policy are also co-authors on this study. Research reported in this article was supported by the National Institutes of Health’s National Heart, Lung, and Blood Institute under award number R01HL115189, as well as by an American Diabetes Association’s Pathway to Stop Diabetes award and the Laidlaw Foundation’s Laidlaw Scholars Leadership & Research Programme. Complete information on methodology, limitations, and conflicts of interest is available in the published paper. 

The content is solely the responsibility of the authors and does not necessarily represent the official views of the funders. 

---

Journal

American Journal of Public Health

DOI

10.2105/AJPH.2026.308499 

GLP Research Reports

 Check out my new blog:

GLP Research Reports

90-120 weekly minutes of strength training may be optimal for lowering death risk

 

Clocking up 90 to 120 weekly minutes of strength (resistance) training may be the sweet spot for lowering the risk of death, suggests a 30 year study, published online in the British Journal of Sports Medicine.

 

The effects were amplified by the addition of aerobic exercise, but no further benefit was apparent above 120 minutes a week of strength training—an amount that was specifically associated with, respectively, 19% and 27% lower risks of dying from cardiovascular and neurological diseases.

 

The benefits of aerobic physical activity on lowering the risk of death are well known, but less clear is the role of muscle strengthening exercise in reducing the risks of death from all and specific causes, solely or jointly with aerobic exercise, say the researchers.

 

To explore this further, they drew on 30 years of monitoring data from 3 large groups of study participants: the Health Professionals Follow-up Study, 1992–2022; the Nurses’ Health Study, 2002–21; and  the Nurses’ Health Study II, 2003–21, comprising a total of 147,374 participants (31,540 men and 115,834 women).

 

Participants were quizzed every 2 years on the amount of time they spent on strength training and aerobic exercise every week for up to 30 years. Aerobic exercise included brisk walking, running, jogging, swimming, cycling, tennis, squash, strenuous outdoor work and stair climbing, while strength training included exercises using weights or body weight, such as press ups, squats, and lunges.

 

The average age of participants at study entry was 54. Those who clocked up more strength training tended to be younger, weigh less, have a healthier lifestyle, and do more aerobic exercise than those who did no strength training.

 

Three quarters (74%) of participants did more than the recommended 150 minutes/week of moderate intensity aerobic exercise, measured as 7.5 MET hours over the long term. METs express the amount of calories expended per minute of physical activity, relative to calories expended at rest. And nearly half (46%) of participants did some strength training.

 

During the 30 year monitoring period, 35,798 study participants died. A higher weekly long term level of strength training was associated with a lower risk of death.

 

After adjusting for potentially influential factors, 90–119 minutes/week of strength training was associated with a 13% lower risk of death from any cause, with no further benefit observed above 120 minutes/week.

 

And 90-119 weekly minutes of strength training was specifically associated with a 19% lower risk of dying from cardiovascular disease, and a 27% lower risk of dying from neurological disease.

 

A reduced risk of cancer was seen only at lower levels: 1–29 mins/week (21% lower) and 30–59 mins/week (18% lower).

 

Compared with those participants with fewer than 7.5 MET hours/week of aerobic exercise and no strength training, those doing 1–59 and 60–119 mins/week of strength training alone had a 7–11% lower risk of death.

 

Aerobic activity alone at any level above 7.5 MET hours/week was associated with a 26–43% lower risk of death.

 

And the lowest risk was observed among those with both high aerobic activity and strength training levels every week: 45% lower risk for 30-44 MET hours/week of aerobic exercise plus 60–119 mins/week of strength training, and 53%-58% lower risks among those with 45+ MET hours/week of aerobic activity, irrespective of strength training level.

 

This is an observational study, and as such, no firm conclusions can be drawn about cause and effect. And the researchers acknowledge various limitations to their study.

 

These include the self reported nature of the data; the exclusion of strength training activities, such as calisthenics and Pilates; no information on the duration of each exercise session or the intensity of strength training, any or all of which might have influenced the findings.

 

Nevertheless they conclude: “Our findings on different dose-response relationships between long-term resistance training with all-cause and cause-specific mortality suggest that different amounts of resistance training may be needed to optimise benefits across outcomes.

 

“The observed pattern that adding resistance training further reduced mortality risk across all levels of aerobic activity up to 45 MET hours/week supports current recommendations encouraging both types of activity to maximise mortality benefits.”

---

Journal

British Journal of Sports Medicine

DOI

10.1136/bjsports-2025-110503