A keto diet might benefit females more than males

 Could a keto diet affect males differently from females? A study from The University of Texas Health Science at San Antonio (UT Health San Antonio) suggests so, and estrogen could promote different protections against adverse effects of the diet like the accumulation of cells expressing markers of age, or senescence.

The study, published Aug. 26 in the journal Cell Reports, found that male, but not female, mice on a ketogenic diet showed the accumulation of cells in organs expressing markers of cellular senescence. A keto diet is a popular low-carbohydrate, high-fat regimen that can help some Type 2 diabetes patients control blood sugar and those with epilepsy manage seizures. Cells expressing senescence markers can contribute to age-related declines in overall bodily function.

“These results suggest sex specificity alters the effects of a ketogenic diet, with important clinical implications,” said David Gius, MD, PhD, assistant dean of research and professor with the Department of Radiation Oncology at UT Health San Antonio, associate cancer director for translational research at the institution’s Mays Cancer Center and investigator for its Barshop Institute for Longevity and Aging Studies.

He is lead author of the study, titled, “Divergent sex-specific effects on a ketogenic diet: Male, but not female, mice exhibit oxidative stress and cellular senescence.”

Ketogenic diets induce ketogenesis, the generation of ketone bodies or water-soluble molecules from fat for use as fuel in place of glucose. They have shown benefits in controlling refractory epilepsy and are being investigated as potential therapies for other health conditions.

In the past decades, keto diets also have become popular in North America and Europe for weight loss.

While the diets can improve certain health parameters, evidence from mice and clinical studies suggest the effects may be dependent on multiple variables, including adherence, metabolism and, importantly, sex, suggesting that hormone status may impact response.

Gius says the role of gender in the response to keto diets has been understudied. One reason is that male mice have been used extensively for in vivo basic and translational research because it was assumed that females would give less consistent results due to variability from the estrous cycle. Recent studies, however, suggest that largely is unfounded.

In the new study, Gius’ team observed a keto-diet-induced increase in cellular senescence only in male mice, except when they were given the female hormone estrogen. Male mice on a keto diet also exhibited an increase in markers of oxidative stress, which is known to contribute to senescence in cells.

Notably, the researchers found, estrogen or estradiol treatment prevented increases in cell senescence and oxidated stress in male mice on a keto diet, as did several established antioxidants.

They also observed that when females were administered tamoxifen, a “selective estrogen receptor inhibitor” that blocks the effects of estrogen, they then exhibited an increase in oxidative stress and cells expressing senescence markers, the same as male mice. “These results strongly suggest that estrogen is an important variable in the response to a ketogenic diet,” Gius said.

The researchers also found that a high-fat diet – comprising more carbohydrates than a keto diet – also induces cellular senescence in male, but not female, mice.

Other authors of the study also are with the Mays Cancer Center, the Barshop Institute and the Long School at UT Health San Antonio, as well as with Houston Methodist Cancer Center, Houston Methodist Research Institute and Galera Therapeutics Inc.
 

Divergent sex-specific effects on a ketogenic diet: Male, but not female, mice exhibit oxidative stress and cellular senescence

Sung-Jen Wei, Joseph Schell, Wei Qian, Martin Silguero, Agne Baseviciene, Wan Hsi Chen, Rolando Trevino Jr., E. Sandra Chocron, Meredith M. Ogle, Mahboubeh Varmazyad, Gloria M. Martinez, Diego Cruz, Brandon Lorenzana, Felix F. Dong, Haiyan Jiang, Alia Nazarullah, Robert A. Beardsley, Kumar Sharma, Jenny Chang, Erin Munkácsy, David Gius

Published Aug. 26, 2025, in Cell Reports

Link to the full study: Divergent sex-specific effects on a ketogenic diet: Male, but not female, mice exhibit oxidative stress and cellular senescence - ScienceDirect

People who skip breakfast and eat late dinners may have a higher risk of osteoporosis

 People who skip breakfast and eat late dinners may have an increased risk of developing osteoporosis, according to a new study published in the Journal of the Endocrine Society.

Lifestyle habits, such as exercise, alcohol consumption and smoking, are known to increase people’s risk of osteoporosis, however little is known about the association between osteoporotic fracture and diet.

“This study aimed to examine the association between lifestyle habits such as diet, and the risk of osteoporotic fracture,” said study author Hiroki Nakajima, M.D., Ph.D., of Nara Medical University in Nara, Japan. “We found skipping breakfast and having late dinners was associated with an increased risk of osteoporosis. Furthermore, these unhealthy eating habits were found to be linked with the accumulation of other lifestyle risk factors such as physical inactivity, smoking and insufficient sleep.”

The researchers used a large health checkup cohort of 927,130 adults (45.3% male and 54.7% female) from a Japanese claims database to find the association between lifestyle factors and the diagnosis of osteoporotic fracture (hip, forearm, vertebral and humeral fractures).

They found people who had unhealthy habits such as smoking, daily alcohol consumption, not enough exercise or sleep, skipping breakfast, and having late dinners, were more likely to be diagnosed with osteoporosis.

“These results suggest that preventing osteoporosis and fractures requires not only healthy eating habits but also a broader effort to improve overall lifestyle behaviors,” Nakajima said.

Ultra-processed foods harm men’s health

 Over the past 50 years, rates of obesity and type-2 diabetes have soared, while sperm quality has plummeted. Driving these changes could be the increasing popularity of ultra-processed foods, which have been linked to a range of poor health outcomes. However, scientists still aren’t sure whether it’s the industrial nature of the ingredients themselves, the processing of the foods, or whether it’s because they lead people to eat more than they should.

An international team of scientists has now discovered that people gain more weight on an ultra-processed diet compared to a minimally processed diet, even when they eat the same number of calories. The study in humans also revealed a diet high in ultra-processed foods introduces higher levels of pollutants that are known to affect sperm quality. The findings were published in the journal Cell Metabolism.

“Our results prove that ultra-processed foods harm our reproductive and metabolic health, even if they’re not eaten in excess. This indicates that it is the processed nature of these foods that makes them harmful,” says Jessica Preston, lead author of the study, who carried out the research during her PhD at the University of Copenhagen's NNF Center for Basic Metabolic Research (CBMR).

Same calories, different outcomes

To get the best possible data, the scientists compared the health impact of unprocessed and ultra-processed diets on the same person. They recruited 43 men aged 20 to 35, who spent three weeks on each of the two diets, with three months ‘washout’ in between. Half started on the ultra-processed and half started on the unprocessed diet. Half of the men also received a high-calorie diet with an extra 500 daily calories, while half received the normal amount of calories for their size, age and physical activity levels. They were not told which diet they were on. Both the unprocessed and ultra-processed diets had the same amount of calories, protein, carbs and fats.

Men gained around 1 kg more of fat mass while on the ultra-processed diet compared to the unprocessed diet, regardless of whether they were on the normal or excess calorie diet. Several other markers of cardiovascular health were also affected.

Ultra-processed foods polluted with endocrine disruptors

The scientists also discovered a worrying increase in the level of the hormone-disrupting phthalate cxMINP, a substance used in plastics, in men on the ultra-processed diet. Men on this diet also saw decreases in their levels of testosterone and follicle-stimulating hormone, which are crucial for sperm production.

“We were shocked by how many body functions were disrupted by ultra-processed foods, even in healthy young men. The long-term implications are alarming and highlight the need to revise nutritional guidelines to better protect against chronic disease.” says the study’s senior author Professor Romain Barrès from the University of Copenhagen’s NNF Center for Basic Metabolic Research, and the Université Côte d’Azur.

Read the paper in Cell Metabolism: Effect of ultra-processed food consumption on male reproductive and metabolic health

High protein increases the risk of cancer-associated venous thromboembolism

 Next to cancer recurrence or progression, cardiovascular diseases are the leading causes of death in cancer survivors. The Surveillance, Epidemiology, and End Results database revealed that among the more than three million who initially survived cancer between 1973 and 2012, 38% eventually succumbed to the disease while 11.3% died from cardiovascular diseases.  Specifically, cancer survivors are at a four to seven-fold higher risk of venous thromboembolism (VTE), which proves fatal in one out of seven cancer patients.

While the effects of high-fat diets have been studied in the context of cancer and cardiovascular disease, sparse information is available on the impact of a high-protein diet and cancer-associated thrombosis.

In a new study from Boston University Chobanian & Avedisian School of Medicine, researchers have found that a high protein diet, or a diet high in amino acid tryptophan (Trp). Trp is abundant in various protein-rich foods increases the risk of cancer-associated VTE in experimental models.

“Although our new findings are based on experimental models, we believe that knowledge gained from this study could prompt interest in further testing relevance to the human condition,” says co-corresponding author Katya Ravid, the Barbara E. Corkey professor at the school.  

The researchers found that experimental models with colon cancer who were fed a high protein diet or a diet rich with Trp experienced more severe development of vascular thrombosis compared to the groups that had been fed a regular balanced diet. They also found that inhibiting the key enzyme responsible for the metabolism of tryptophan reduced the severity of vascular injury. Finally, they found that Kynurenine, a known metabolite of tryptophan, has an effect on blood coagulation factors that are known to promote thrombosis.

According to the researchers, this work has potential implications at the individual patient and population levels. “Nutrition management is an integral component of cancer patient care. Patients with cancer are often advised to increase their dietary protein intake to compensate for cancer-cachexia (involuntary weight loss, muscle wasting, and loss of appetite, leading to significant weakness and fatigue) and chemotherapy side-effects. At times, these patients receive parenteral nutrition (feeding directly into the bloodstream), including approximately five to eight times more Trp than dietary recommendation,” explains co-corresponding author Vipul Chitalia, MD, PhD, professor of medicine. 

These findings appear online in the journal Blood Advances.

Overweight older adults face lower risk of death after major surgery

 Older adults who are overweight may face a lower risk of death in the first 30 days following major elective surgery compared with those who have a normal body mass index (BMI), new research suggests.

The study, to be published August 26 in the peer-reviewed JAMA Network Open, examined outcomes in older surgical patients and found that being overweight (BMI 25–29.9) was associated with the lowest short-term mortality rates. In contrast, normal and underweight patients had significantly higher risk of death.

“Traditional surgical guidelines often emphasize having a normal BMI before surgery, but our findings suggest that these recommendations may need to be reconsidered for older adults,” said lead author Dr. Cecilia Canales, assistant professor in the Department of Anesthesiology & Perioperative Medicine at the David Geffen School of Medicine at UCLA. “Older adults have different physiological considerations, and moderate excess weight may actually be protective in the short term after surgery.”

The researchers analyzed data from 414 adults aged 65 and older undergoing major elective surgery at a large academic center in Southern California between February 2019 and January 2022. Patients were categorized by BMI and compared for 30-day and one-year mortality, postoperative delirium, discharge disposition, and complications.

Patients in the overweight category had a 0.8% 30-day all-cause mortality rate, compared to 18.8% for those with a normal BMI, a difference that remained significant after adjusting for factors such as age, frailty, and comorbidities - including whether a patient had cancer. Underweight patients had a 15.0% 30-day mortality rate.

“This study adds to a growing body of evidence on the so-called ‘obesity paradox,’ where a higher BMI appears to be linked with better survival in certain older adult populations,” said co-author Dr. Catherine Sarkisian, professor of medicine in the division of general internal medicine and health services research at the Geffen School. “It’s important to tailor preoperative evaluation to the physiology of older patients.”

The authors note that these findings may have implications for preoperative counseling and BMI-based surgical risk calculators, which are often derived from younger or mixed-age populations. They recommend further research to explore the biological and clinical mechanisms behind this association and to inform surgical guidelines for older adults.

Mediterranean diet may offset genetic risk of Alzheimer's

 Researchers found dietary changes may help improve cognitive health and stave off dementia

A new study led by investigators from Mass General Brigham, Harvard T.H. Chan School of Public Health, and the Broad Institute of MIT and Harvard suggests that a Mediterranean-style diet may help reduce dementia risk. The study, published in Nature Medicine, found that people at the highest genetic risk for Alzheimer's disease benefited more from following a Mediterranean-style diet, showing a greater reduction in dementia risk compared to those at lower genetic risk.

"One reason we wanted to study the Mediterranean diet is because it is the only dietary pattern that has been causally linked to cognitive benefits in a randomized trial," said study first author Yuxi Liu, PhD, a research fellow in the Department of Medicine at Brigham and Women's Hospital, a founding member of the Mass General Brigham healthcare system, and a postdoctoral fellow at the Harvard Chan School and Broad. "We wanted to see whether this benefit might be different in people with varying genetic backgrounds, and to examine the role of blood metabolites, the small molecules that reflect how the body processes food and carries out normal functions."

Over the last few decades, researchers have learned more about the genetic and metabolic basis of Alzheimer's disease and related dementias. These are among the most common causes of cognitive decline in older adults. Alzheimer's disease is known to have a strong genetic component, with heritability estimated at up to 80%.

One gene in particular, apolipoprotein E (APOE), has emerged as the strongest genetic risk factor for sporadic Alzheimer's disease — the more common type develops later in life and is not directly inherited in a predictable pattern. People who carry one copy of the APOE4 variant have a 3-to-4-fold higher risk of developing Alzheimer's. People with two copies of the APOE4 variant (called APOE4 homozygous) have a 12-fold higher risk of Alzheimer's than those without.

To explore how the Mediterranean diet may reduce dementia risk and influence blood metabolites linked to cognitive health, the team analyzed data from 4,215 women in the Nurses' Health Study, following participants from 1989 to 2023 (average age 57 at baseline). To validate their findings, the researchers analyzed similar data from 1,490 men in the Health Professionals Follow-Up Study, followed from 1993 to 2023.

Researchers evaluated long-term dietary patterns using food frequency questionnaires and examined participants' blood samples for a broad range of metabolites. Genetic data were used to assess each participant’s inherited risk for Alzheimer’s disease. Participants were then followed over time for new cases of dementia. A subset of 1,037 women underwent regular telephone-based cognitive testing.

They found that the people following a more Mediterranean-style diet had a lower risk of developing dementia and showed slower cognitive decline. The protective effect of the diet was strongest in the high-risk group with two copies of the APOE4 gene variant, suggesting that diet may help offset genetic risk.

"These findings suggest that dietary strategies, specifically the Mediterranean diet, could help reduce the risk of cognitive decline and stave off dementia by broadly influencing key metabolic pathways," Liu said. "This recommendation applies broadly, but it may be even more important for individuals at a higher genetic risk, such as those carrying two copies of the APOE4 genetic variant."

A study limitation was that the cohort consisted of well-educated individuals of European ancestry. More research is needed in diverse populations.

In addition, although the study reveals important associations, genetics and metabolomics are not yet part of most clinical risk prediction models for Alzheimer's disease. People often don't know their APOE genetics. More work is needed to translate these findings into routine medical practice.

"In future research, we hope to explore whether targeting specific metabolites through diet or other interventions could provide a more personalized approach to reducing dementia risk," Liu said.

Mediterranean diet combined with calorie reduction and exercise may reduce risk of type 2 diabetes by nearly one-third

Key points:

• Those who adhered to a Mediterranean diet, reduced their caloric intakes, engaged in moderate exercise, and received professional weight loss support had a 31% lower risk of developing type 2 diabetes compared to those who adhered to a Mediterranean diet alone.
• The findings come from PREDIMED-Plus, the largest nutrition and lifestyle clinical trial ever conducted in Europe.

Boston, MA—A Mediterranean-style diet, in combination with reduced caloric intake, moderate physical activity, and professional support for weight loss, may cut the risk of type 2 diabetes (T2D) by 31%, according to a new study co-authored by researchers at Harvard T.H. Chan School of Public Health.

The study will be published August 25, 2025, in the Annals of Internal Medicine.

“We’re facing a global epidemic of diabetes,” said co-author Frank Hu, Fredrick J. Stare Professor of Nutrition and Epidemiology and chair of the Department of Nutrition. “With the highest-level evidence, our study shows that modest, sustained changes in diet and lifestyle could prevent millions of cases of this disease worldwide.”

Prior research has linked the Mediterranean diet—which emphasizes high intake of fruits, vegetables, whole grains, and healthy fats, moderate intake of dairy and lean proteins, and little to no intake of red meat—to better health outcomes, including lowered risk of T2D through improved insulin sensitivity and reduced inflammation. 

A team of collaborators from the PREDIMED-Plus clinical trial, the largest nutrition and lifestyle randomized trial in Europe, sought to understand how the diet’s benefits may be enhanced with additional healthy lifestyle changes.

The researchers, from 23 universities in Spain and Harvard Chan School, split 4,746 PREDIMED-Plus participants into an intervention group and a control group and followed their health outcomes for six years. The intervention group adhered to a Mediterranean diet; reduced their caloric intake by about 600 calories per day; engaged in moderate physical activity, such as brisk walking and strength and balance exercises; and received professional support for weight loss control. The control group adhered to a Mediterranean diet without calorie restriction, exercise guidance, or professional support. Participants ranged from age 55 to 75, were overweight or obese, and had metabolic syndrome, but were free of T2D at baseline.

The study found that those in the intervention group had a 31% lower risk of developing T2D compared to those in the control group. Additionally, the intervention group lost an average of 3.3 kilograms and reduced their waist circumference by 3.6 centimeters, compared to 0.6 kilograms and 0.3 centimeters in the control group.

“In practical terms, adding calorie control and physical activity to the Mediterranean diet prevented around three out of every 100 people from developing diabetes—a clear, measurable benefit for public health,” said co-author Miguel Martínez-González, professor at the University of Navarra and adjunct professor of nutrition at Harvard Chan School.

Animal protein not linked to higher mortality risk

Eating animal-sourced protein foods is not linked to a higher risk of death and may even offer protective benefits against cancer-related mortality, new research finds.  

 

The study, published in Applied Physiology, Nutrition, and Metabolism, analyzed data from nearly 16,000 adults aged 19 and older using the National Health and Nutrition Examination Survey (NHAMES III).

 

Researchers examined how much animal and plant protein people typically consume and whether those patterns were associated with their risk of dying from heart disease, cancer or any cause. 

 

They found no increased risk of death associated with higher intake of animal protein. In fact, the data showed a modest but significant reduction in cancer-related mortality among those who ate more animal protein. 

 

“There’s a lot of confusion around protein – how much to eat, what kind and what it means for long-term health. This study adds clarity, which is important for anyone trying to make informed, evidence-based decisions about what they eat,” explains Stuart Phillips, Professor and Chair of the Department of Kinesiology at McMaster University, who supervised the research. 

 

To ensure reliable results, the team employed advanced statistical methods, including the National Cancer Institute (NCI) method and multivariate Markov Chain Monte Carlo (MCMC) modelling, to estimate long-term dietary intake and minimize measurement error. 

 

“It was imperative that our analysis used the most rigorous, gold standard methods to assess usual intake and mortality risk. These methods allowed us to account for fluctuations in daily protein intake and provide a more accurate picture of long-term eating habits,” says Phillips. 

 

The researchers found no associations between total protein, animal protein or plant protein and risk of death from any cause, cardiovascular disease, or cancer. When both plant and animal protein were included in the analysis, the results remained consistent, suggesting that plant protein has a minimal impact on cancer mortality, while animal protein may offer a small protective effect.

 

Observational studies like this one cannot prove cause and effect; however, they are valuable for identifying patterns and associations in large populations. Combined with decades of clinical trial evidence, the findings support the inclusion of animal proteins as part of a healthy dietary pattern. 

 

“When both observational data like this and clinical research are considered, it’s clear both animal and plant protein foods promote health and longevity,” says lead researcher Yanni Papanikolaou, MPH, president, Nutritional Strategies.

 

Plant-based diets can reduce the risk of multimorbidity

 In a large-scale multinational study involving over 400,000 women and men aged 37 to 70 years from six European countries, researchers from the University of Vienna, in collaboration with the International Agency for Research on Cancer (IARC) (France) and the Kyung Hee University (Republic of Korea), investigated dietary habits and disease trajectories.  The comprehensive data analysis shows that a plant-based diet is associated with reduced risk of multimorbidity of cancer and cardiometabolic diseases. The study has been published in the journal The Lancet Healthy Longevity. 

The study used data from two large European cohort studies, the European Prospective Investigation into Cancer and Nutrition (EPIC) study and UK Biobank. Based on data from six European countries (Italy, Spain, the United Kingdom, Germany, the Netherlands, and Denmark), the researchers provide further evidence that plant-based dietary habits can influence the development of multimorbidity. Results from the UK Biobank, for example, showed that adults with a higher adherence to a plant-based diet had a 32% lower risk of multimorbidity compared to those with a lower adherence. “You don’t have to cut out animal products entirely, “said study lead and nutritional epidemiologist Reynalda Córdova. “Shifting towards a more plant-based diet can already have a positive impact.” The study also examined differences in the risk of multimorbidity between middle-aged and older adults. Higher adherence to a plant-based diet was associated with a lower risk of cancer and cardiometabolic multimorbidity in both adults younger than 60 years and in those aged 60 years or older. Multimorbidity describes the occurrence of two or more chronic diseases in one person and is a growing health problem worldwide, particularly among adults 60 years and older.

Lower risk of cancer, diabetes, and cardiovascular disease

The results: A stronger adherence to a healthy plant-based diet was associated with a lower risk of cancer, cardiometabolic disease (diabetes and cardiovascular diseases), and multimorbidity, both in adults under 60 and those over 60. “Our study highlights that a healthy, plant-based diet not only influences individual chronic diseases but can also reduce the risk of developing multiple chronic diseases at the same time, in both middle-aged and older people,” Córdova summarized. 

“The results show how important a predominantly plant-based diet is for our health and thus reinforce the new Austrian dietary recommendations, which emphasize plant-based food with a low proportion of animal-based foods. A co-benefit of a plant-based diet are lower greenhouse gas emissions and land use,” adds Karl-Heinz Wagner form the University of Vienna, co-author of the study and president of the Austrian Society for Nutrition. 

Fruit, vegetables, whole grains, and legumes have a positive effect

A healthy plant-based dietary pattern included for example, a higher intake of fruits, vegetables, whole grains, legumes and vegan sausages or burgers and a lower intake of meat and meat products. The findings suggest that a diet consisting mainly of healthy plant foods and small amounts of animal-based foods can contribute to maintaining health into older age. 

The authors conclude that dietary guidelines, public health measures, and interventions should consider that a diet primarily composed of plant-based foods with small amounts of animal-based products may help prevent multimorbidity related to cancer and cardiometabolic diseases. 

Omega-3’s could protect women against Alzheimer’s

 Omega fatty acids could protect against Alzheimer’s disease in women, new research has found.

Analysis of lipids – fat molecules that perform many essential functions in the body – in the blood found there was a noticeable loss of unsaturated fats, such as those that contain omega fatty acids, in the blood of women with Alzheimer’s disease compared to healthy women.

Scientists found no significant difference in the same lipid molecule composition in men with Alzheimer’s disease compared to healthy men, which suggests that those lipids have a different role in the disease according to sex. Fats perform important roles in maintaining a healthy brain, so this study could indicate why more women are diagnosed with the disease.

The study, published today in Alzheimer's & Dementia: The Journal of the Alzheimer's Association by scientists from King’s College London and Queen Mary University London, is the first to reveal the important role lipids could have in the risk for Alzheimer’s between the sexes.

Senior author Dr Cristina Legido-Quigley, from King’s College London, said: “Women are disproportionately impacted by Alzheimer’s Disease and are more often diagnosed with the disease than men after the age of 80. One of the most surprising things we saw when looking at the different sexes was that there was no difference in these lipids in healthy and cognitively impaired men, but for women this picture was completely different. The study reveals that Alzheimer's lipid biology is different between the sexes, opening new avenues for research.”

The scientists took plasma samples from 841 participants who had Alzheimer’s Disease, mild cognitive impairment and cognitively health controls and and were measured for brain inflammation and damage.

They used mass spectrometry to analyse the 700 individual lipids in the blood. Lipids are a group of many molecules. Saturated lipids are generally considered as ‘unhealthy’ or ‘bad’ lipids, while unsaturated lipid, which sometime contains omega fatty acids, are generally considered ‘healthy’.

Scientists saw a steep increase in lipids with saturation – the ‘unhealthy lipids’ – in women with Alzheimer’s compared to the healthy group. The lipids with attached omega fatty acids were the most decreased in the Alzheimer’s group.

Now, the scientists say there is a statistical indication that there is a causal link between Alzheimer’s Disease and fatty acids. But a clinical trial is necessary to confirm the link.

Dr Legido-Quigley added: “Our study suggests that women should make sure they are getting omega fatty acids in their diet – through fatty fish or via supplements. However, we need clinical trials to determine if shifting the lipid composition can influence the biological trajectory of Alzheimer’s Disease.”

 

Dr Asger Wretlind, first author of the study from King’s College London, said: “Scientists have known for some time that more women than men are diagnosed with Alzheimer’s disease. Although this still warrants further research, we were able to detect biological differences in lipids between the sexes in a large cohort, and show the importance of lipids containing omegas in the blood, which has not been done before. The results are very striking and now we are looking at how early in life this change occurs in women.”

Dr Julia Dudley, Head of Research at Alzheimer’s Research UK says: “In the UK, two in three people living with dementia are women. This could be linked to living longer, or other risk factors like social isolation, education, or hormonal changes from the menopause being at play.

“While this study shows that women with Alzheimer’s had lower levels of some unsaturated fats compared with men, further work is needed. This includes understanding the mechanisms behind this difference and finding out if lifestyle changes, including diet could have a role. Future research should also be carried out in a more ethnically diverse population to see if the same effect is seen.

“Understanding how the disease works differently in women could help doctors tailor future treatments and health advice. Alzheimer’s Research UK is proud to be funding this work that will bring us a step closer to a cure.”

Menopause misinformation is harming care, warn experts

 Many direct to consumer menopause services are unnecessary and do not improve care, warn experts in The BMJ today.

They argue that the sharp rise in commercial services for women seeking relief for menopausal symptoms raises concerns about the reliability and potential commercial bias of the information, and that symptoms are best assessed by a thorough clinical history with treatment decisions guided by clinical response and patient preferences.

One of the most troubling trends arising from this surge is the promotion of routine hormone panel testing for the evaluation of menopausal symptoms, they write. These tests can cost hundreds of dollars and are marketed to patients and clinicians as necessary for “individualising” hormone therapy.

Yet in reality, these tests are of limited clinical use because there is no clearly defined therapeutic window for menopausal hormone therapy, and some testing techniques do not offer accurate or precise assessment of hormone levels.

For perimenopause and menopause, hormone testing offers no reliable way to determine who will benefit from treatment, when the final menstrual period will occur, or whether it is safe to discontinue contraception, they explain.

Clinical guidelines from the British Menopause Society, National Institute for Health and Care Excellence, American College of Obstetricians and Gynecologists and others agree: in women over age 45 presenting with validated symptoms of menopause, including menstrual irregularity, menopause is a clinical diagnosis, and hormone testing is unnecessary.

Despite this, many women now present with detailed hormone panels from wellness providers or online services that are often used to justify taking custom-made hormone preparations or supplements based on marginal deviations from hormone thresholds that are not grounded in evidence, write the authors.

Such custom-made hormone preparations (known as compounded hormone regimens) are not regulated in the same way as standard menopausal hormone therapy and have not been tested for effectiveness and safety.

There is also concern that inconsistencies in the quantities of oestrogen or progestogen in compounded hormone regimens can result in abnormal cell growth or cancer in the womb (uterus) lining, they add.

Until we can establish individualised target hormone levels, there is no role for commercial hormonal panel testing to guide therapy, they argue. In the meantime, such testing offers only a false sense of precision.

They acknowledge that innovation is needed but suggest that the normalisation of hormone panel testing could be a symptom of a larger problem: the commercialisation of women’s health and a movement away from evidence based practice. 

For midlife women, effective treatment begins not with numbers, but with listening, they conclude.

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Journal

The BMJ

DOI

10.1136/bmj.r1695 

Companies may be misleading parents with “outrageous claims” about banking baby teeth

Parents are spending thousands of pounds to bank stem cells from their children’s milk teeth – but the recipient companies’ claims about their future medical value are unproven and potentially misleading, reveals an investigation by The BMJ, published today.

The companies’ claims include that stem cells banked from teeth are already being used in treatments for autism and diabetes. They also highlight current research using stem cells in multiple sclerosis, Parkinson’s disease, and heart attacks.

Tooth stem cell banking involves parents sending their children’s lost milk teeth to a laboratory where the dental pulp stem cells are harvested and stored. The service costs around £1900 (€2189; $2573) with an additional annual storage fee of £95, explains freelance journalist Emma Wilkinson. 

The three companies in the UK offering tooth stem cell banking – Future Health Biobank, BioEden and Stem Protect – all operate through one laboratory. 

Future Health Biobank says on its website that it has released 26 tooth stem cell samples for treatment, including for autism, type 1 diabetes, and knee cartilage regeneration, all to private clinics in North America.

BioEden states it has "already witnessed the remarkable evidence of these ongoing developments” among its own customers, while Stem Protect cites cleft palate repair, sickle cell disease, HIV/AIDS, severe combined immunodeficiency, and knee cartilage repair under a section of its website headed, ‘What treatments are tooth stem cells used for?’

But several experts are concerned about the claims being made, which they say risk exploiting parents, with the autism treatment promise deemed particularly “outrageous.”

Jill Shepherd, senior lecturer in stem cell biology at the University of Kent, says companies are selling the “potential” for something that is not yet borne out by the science. “There is a lack of evidence and a paucity of research using dental pulp stem cells to treat patients.”

Sufyan Hussain, an investigator on the UK arm of a global clinical trial evaluating stem cell therapy for type 1 diabetes, also has concerns about what is being promised. “At present, there isn't a definitive answer regarding the optimal source of stem cells for future diabetes therapies,” he says.

Tim Nicholls, assistant director of policy, research and strategy at the National Autistic Society in the UK, adds: “It’s outrageous that tooth stem cell procedures are being advertised to parents with the false claim of ‘treating’ autism.

“Autism is not a disease or illness, it cannot be treated and there is no cure. It is dangerous and morally bankrupt to target potentially vulnerable people with expensive procedures that could, in fact, cause harm.”

Experts are also concerned about the lack of independent information on tooth stem cell banking to help consumers make a fully informed choice, and say more oversight is needed of the information being used to promote the practice. 

Jill Shepherd also believes parents should be given more information on what type of tests are done to validate that stem cells are present in the stored samples, that the samples have been collected properly, and the evidence on how long such samples can be viably stored.

The BMJ has raised several concerns about how the service is promoted on all three company websites with the Advertising Standards Agency, which it says it will review.

In response, Future Health Biobank says it is reviewing how information on its site is presented to ensure “readers can clearly distinguish between client experiences and formally published clinical outcomes.” 

The company also says it has a “robust, ongoing, storage stability validation programme” with quality control testing “to ensure that there is no deterioration in the integrity, viability or future potential of biological samples.”

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Journal

The BMJ

DOI

10.1136/bmj.r1491  

Diet rich in omega-3 fatty acids may help ward off short sightedness in children

 

On the other hand, high intake of saturated fats may boost risk of eye condition

A diet rich in omega-3 fatty acids, found predominantly in fish oils, may help ward off the development of short sightedness (myopia) in children, while a high intake of saturated fats, found in foods such as butter, palm oil, and red meat, may boost the risk of the condition, finds research published online in the British Journal of Ophthalmology.

The global prevalence of myopia is rising, especially in East Asia, and it’s predicted that around half of the world’s population will be affected by 2050, note the researchers.

Risk factors are thought to include excessive screen time and too little time spent outdoors, as well as inherited susceptibility, they explain. 

Omega-3 polyunsaturated fatty acids (ω-3 PUFAs), which can only be obtained from the diet, are thought to improve/prevent several chronic eye conditions, including dry eye disease and age-related macular degeneration. But whether they can help ward off myopia isn’t clear as studies to date have been experimental and haven’t included people.

To explore this further, the researchers drew on 1005 Chinese 6-8 year olds, randomly recruited from the population based Hong Kong Children Eye Study, which is tracking the development of eye conditions and potential risk factors.

The children’s eyesight was assessed and their regular diet measured by a food frequency questionnaire, completed with the help of their parents. This included 280 food items categorised into 10 groups: bread/cereals/pasta/rice/noodles; vegetables and legumes; fruit; meat; fish; eggs; milk and dairy products; drinks; dim sum/snacks/fats/oils; and soups.

Intakes of energy, carbohydrate, proteins, total fat, saturated fats, monounsaturated fats, PUFAs, cholesterol, iron, calcium, vitamins A and C, fibre, starch, sugar and nutrients were then calculated, based on the questionnaire responses.

The amount of time the children spent outdoors in leisure and during sports activities, reading and writing, and on screens during weekdays and at the weekend was calculated from validated questionnaire responses. 

In all, around a quarter of the children (276; 27.5%) had myopia. Higher dietary intake of omega-3 fatty acids was associated with a lower risk of the condition.

Axial length—measurement of the eye from the cornea at the front to the retina at the back, and an indicator of myopia progression—was longest in the 25% of children with the lowest dietary intake of omega-3 fatty acids, after accounting for influential factors, including age, sex, weight (BMI), the amount of time spent in close work and outdoors, and parental myopia. 

It was shortest in the 25% of children with the highest dietary intake of omega-3 fatty acids.

Similarly, cycloplegic spherical equivalent (SE), which measures refractive error, such as the degree of shortsightedness, was highest in those with the lowest omega-3 fatty acid intake and lowest in those with the highest intake.

But these findings were reversed for the 25% of children with the highest saturated fat intake, compared with the 25% of those with the lowest. None of the other nutrients was associated with either measure or myopia.

This is an observational study, and as such, can’t establish causal and temporal factors. And the researchers acknowledge that food frequency questionnaires rely on recall and only provide a snapshot in time of diet. Nor was there objective evidence of nutritional intake from blood samples.

The prevalence of myopia in Hong Kong is also among the highest in the world. And whether the findings might apply to other ethnic groups with different lifestyles and less myopia remains to be verified, they add.

But omega-3 fatty acids may suppress myopia by increasing blood flow through the choroid, a vascular layer in the eye, responsible for delivering nutrients and oxygen, and so staving off scleral hypoxia—oxygen deficiency in the white of the eye and a key factor in the development of shortsightedness, they suggest. 

And they conclude: “This study provides the human evidence that higher dietary ω-3 PUFA intake is associated with shorter axial length and less myopic refraction, highlighting ω-3 PUFAs as a potential protective dietary factor against myopia development.”

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Journal

British Journal of Ophthalmology

DOI

10.1136/bjo-2024-326872 

Your morning coffee really does make you happier

 People who regularly consume caffeine are usually in a better mood after a cup of coffee or another caffeinated drink—an effect that is much more pronounced in the morning than later in the day. This finding comes from a new study by researchers at Bielefeld University and the University of Warwick, published in the journal Scientific Reports. Participants reported feeling significantly happier and more enthusiastic on those mornings compared with other days at the same hour when they had not yet had coffee.

Links to negative moods such as sadness and feeling upset were also observed, though these effects were less pronounced: after drinking coffee, participants felt slightly less sad or upset than on comparable days without coffee. Unlike the boost in positive emotions, this effect was not dependent on the time of day.

In total, 236 young adults in Germany were studied over a period of up to four weeks. Participants completed short questionnaires on their smartphones seven times a day, indicating their current mood and whether they had consumed a caffeinated drink in the preceding 90 minutes. Accordingly, the study focused on caffeine consumption in everyday life, not just in artificial laboratory settings.

Perceived effect regardless of consumption habits

The researchers also investigated whether coffee has different effects on different individuals. Justin Hachenberger from the Bielefeld University in Germany says, ‘We were somewhat surprised to find no differences between individuals with varying levels of caffeine consumption or differing degrees of depressive symptoms, anxiety, or sleep problems. The links between caffeine intake and positive or negative emotions were fairly consistent across all groups.’

The researchers expected that people with higher levels of anxiety would experience negative mood changes, such as increased nervousness, after consuming caffeine. However, Hachenberger emphasises that people who react to caffeine in a bad way may avoid it and that the study did not include people who completely abstain from caffeine.

Role of caffeine withdrawal symptoms remains unclear

The researchers explain the mood-boosting effect of caffeine on morning mood with its ability to block adenosine receptors, which promotes wakefulness and makes people feel more energetic. ‘Caffeine works by blocking adenosine receptors, which can increase dopamine activity in key brain regions—an effect that studies have linked to improved mood and greater alertness’, says Professor Anu Realo from the University of Warwick.

Yet, it remains unclear whether these effects are related to a reduction in withdrawal symptoms after a night’s sleep. ‘Even people with moderate caffeine consumption can experience mild withdrawal symptoms that disappear with the first cup of coffee or tea in the morning’, says Anu Realo.

Caffeine consumption: a universal habit

‘Around 80 per cent of adults worldwide consume caffeinated beverages, and the use of such stimulating substances dates far back in human history’, says Professor Sakari Lemola from Bielefeld University, the study’s senior author. ‘Even wild animals consume caffeine; bees and bumblebees prefer nectar from plants that contain caffeine.’

Still, the study authors caution that caffeine can lead to dependence. Excessive intake is linked to various health risks, and consuming it later in the day can lead to sleep problems.

Published in a highly cited journal

The journal Scientific Reports, in which the study was published, is the third most cited scientific journal in the world, according to its own information. Data provider Clarivate reports an impact factor of 3.9 (2024).

New high blood pressure guideline emphasizes prevention, early treatment to reduce CVD risk

 Guideline Highlights:

• Nearly half of all adults in the U.S. have high blood pressure (≥130/80 mm Hg), which is the #1 preventable risk factor for cardiovascular disease, including heart attack, stroke and heart failure, as well as kidney disease, cognitive decline and dementia.
• A new joint guideline from the American Heart Association and the American College of Cardiology advises earlier treatment that includes lifestyle modification and medications as appropriate, recommends close blood pressure management before, during and after pregnancy, and highlights using the new PREVENT™ risk calculator to estimate a person’s cardiovascular disease risk to tailor treatment.
• The new guideline also reinforces the importance of healthy lifestyle behaviors, such as eating a nutritious diet, being physically active, and maintaining or achieving a healthy weight.
• More recent research confirms that blood pressure affects brain health, including cognitive function and dementia, so early treatment is recommended for people diagnosed with high blood pressure to maintain brain health and cognition.
• High blood pressure before, during and after pregnancy is important to monitor and treat quickly to reduce the risk of short- and long-term serious complications including preeclampsia.
• The guideline, led by the American Heart Association and American College of Cardiology Joint Committee on Clinical Practice Guidelines, was developed in collaboration with and endorsed by 11 other health care organizations: the American Academy of Physician Associates; the American Association of Nurse Practitioners; the American College of Clinical Pharmacy; the American College of Preventive Medicine; the American Geriatrics Society; the American Medical Association; the American Society of Preventive Cardiology; the Association of Black Cardiologists; the National Medical Association; the Preventive Cardiovascular Nurses Association; and the Society of General Internal Medicine.

Preventing and managing high blood pressure with healthy lifestyle behaviors, such as following a heart-healthy diet including reducing salt intake, staying physically active, maintaining a healthy weight and managing stress—combined with early treatment with medication to lower blood pressure if necessary—are recommended to reduce the risk of heart attack, stroke, heart failure, kidney disease, cognitive decline and dementia, according to a new clinical guideline published today in the American Heart Association’s peer-reviewed journals Circulation and Hypertension, and in JACC, the flagship journal of the American College of Cardiology.

The “2025 AHA / ACC / AANP / AAPA / ABC / ACCP / ACPM / AGS / AMA / ASPC / NMA / PCNA / SGIM Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults” replaces the 2017 guideline and includes new or updated recommendations for blood pressure management based on the latest scientific evidence to achieve the best health outcomes for patients.

The new guideline reflects several major changes since 2017, including use of the American Heart Association’s PREVENTTM (Predicting Risk of cardiovascular disease EVENTs) risk calculator to estimate cardiovascular disease risk. It also provides updated guidance on medication options, including the early treatment for high blood pressure to reduce the risk of cognitive decline and dementia; use of specific medications including the possible addition of newer therapies such as GLP-1 medications for some patients with high blood pressure and overweight or obesity, and recommendations for managing high blood pressure before, during and after pregnancy.

High blood pressure (including stage 1 or stage 2 hypertension) affects nearly half (46.7%) of all adults in the U.S., is the leading cause of death in the U.S. and around the world. The blood pressure criteria remain the same as the 2017 guideline:

• normal blood pressure is less than 120/80 mm Hg;
• elevated blood pressure is 120-129/80 mm Hg;
• stage 1 hypertension is 130-139 mm Hg or 80-89 mm Hg; and
• stage 2 hypertension is ≥140 mm Hg or ≥90 mm Hg. 

“High blood pressure is the most common and most modifiable risk factor for heart disease,” said Chair of the guideline writing committee Daniel W. Jones, M.D., FAHA, dean and professor emeritus of the University of Mississippi School of Medicine in Jackson, Mississippi, and was a member of the writing committee for the 2017 high blood pressure guideline. “By addressing individual risks earlier and offering more tailored strategies across the lifespan, the 2025 guideline aims to aid clinicians in helping more people manage their blood pressure and reduce the toll of heart disease, kidney disease, Type 2 diabetes and dementia.”

“This updated guideline is designed to support health care professionals—from primary care teams to specialists, and to all clinicians across health systems—with the diagnosis and care of people with high blood pressure. It also empowers patients with practical tools that can support their individual health needs as they manage their blood pressure, whether through lifestyle changes, medications or both,” Jones said.

Importance of healthy lifestyle

The new guideline reaffirms the critical role healthy lifestyle behaviors play in preventing and managing high blood pressure, and it encourages health care professionals to work with patients to set realistic, achievable goals. Healthy behaviors such as those in Life’s Essential 8, the American Heart Association’s metrics for heart health, remain the first line of care for all adults.

Specific blood pressure-related guidance includes:

• limiting sodium intake to less than 2,300 mg per day, moving toward an ideal limit of 1,500 mg per day by checking food labels (most adults in the U.S. get their sodium from eating packaged and restaurant foods, not the salt shaker);
• ideally, consuming no alcohol or for those who choose to drink, consuming no more than two drinks per day for men and no more than one drink per day for women;
• managing stress with exercise, as well as incorporating stress-reduction techniques like meditation, breathing control or yoga;
• maintaining or achieving a healthy weight, with a goal of at least a 5% reduction in body weight in adults who have overweight or obesity;
• following a heart healthy eating pattern, for example the DASH eating plan, which emphasizes reduced sodium intake and a diet high in vegetables, fruits, whole grains, legumes, nuts and seeds, and low-fat or nonfat dairy, and includes lean meats and poultry, fish and non-tropical oils;
• increasing physical activity to at least 75-150 minutes each week including aerobic exercise (such as cardio) and/or resistance training (such as weight training); and
• home blood pressure monitoring is recommended for patients to help confirm office diagnosis of high blood pressure and to monitor, track progress and tailor care as part of an integrated care plan.  

Addressing each of these lifestyle factors is especially important for people with high blood pressure and other major risk factors for cardiovascular disease because it may prevent, delay or treat elevated or high blood pressure.

New risk calculator and earlier intervention

The new guideline recommends that health care professionals use the PREVENTTM risk calculator to estimate a person’s risk of a heart attack, stroke or heart failure. Developed by the American Heart Association in 2023, PREVENTTM is a tool to estimate 10- and 30-year risk of cardiovascular disease in people ages 30-79 years. It includes variables such as age, sex, blood pressure, cholesterol levels and other health indicators, including zip code as a proxy for social drivers of health. It is the first risk calculator that combines measures of cardiovascular, kidney and metabolic health to estimate risk for cardiovascular disease. More precise risk estimates can help guide treatment decisions personalized for each individual.

In addition to the use of the PREVENTTM risk assessment tool, the new guideline recommends two important changes to laboratory testing for initial evaluation.

• The ratio of urine albumin and creatinine (a test that assesses kidney health) is now recommended for all patients with high blood pressure. It was recommended as an optional test in the 2017 guideline.
• The guideline also expands the indication for use of the plasma aldosterone-to-renin ratio test as a screening tool for primary aldosteronism in more patients including those with obstructive sleep apnea. (Primary aldosteronism is a condition that occurs when the adrenal glands make too much aldosterone, leading to high blood pressure and low potassium levels.)
• Screening for primary aldosteronism may also be considered in adults with stage 2 hypertension to increase rates of detection, diagnosis and targeted treatment.

Association of high blood pressure with cognitive decline and dementia

While high blood pressure is a leading cause of heart attack and stroke, the new guideline highlights other serious risks. More recent research confirms that blood pressure affects brain health, including cognitive function and dementia. High blood pressure can damage small blood vessels in the brain, which is linked to memory problems and long-term cognitive decline. The guideline recommends early treatment for people diagnosed with high blood pressure with a goal of systolic blood pressure (top number) goal of <130 mm Hg for adults with high blood pressure to prevent cognitive impairment and dementia.

Tailored approaches to medication for high blood pressure

For many people with high blood pressure, especially those who have Type 2 diabetes, obesity or kidney disease, more than one medication may be needed to lower blood pressure to meet the <130/80 mm Hg criteria. The guideline highlights several types of blood pressure medications to initiate treatment, including angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor blockers (ARBs), long-acting dihydropyridine calcium channel blockers and thiazide-type diuretics. If blood pressure remains high after one medication, clinicians may individualize treatment to either increase the dose or add a second medication from a different medication class.

The guideline maintains the recommendation to begin treatment with two medications at once – preferably in a single combination pill - for people with blood pressure levels 140/90 mm Hg or higher (stage 2 hypertension). The guideline also suggests possible addition of newer therapies such as GLP-1 medications for some patients with high blood pressure and overweight or obesity.

High blood pressure and pregnancy

High blood pressure during pregnancy can have lasting effects on the mother’s health, including an increased risk of future high blood pressure and cardiovascular conditions. Without treatment, high blood pressure during pregnancy can lead to serious complications, such as preeclampsia, eclampsia, stroke, kidney problems and/or premature delivery. Women with high blood pressure who are planning a pregnancy or are pregnant should be counseled about the potential benefits of low-dose aspirin (81 mg/day) to reduce the risk of preeclampsia.

For pregnant women with chronic hypertension (high blood pressure before pregnancy or diagnosed before 20 weeks of pregnancy), the new guideline recommends treatment with certain medications when systolic blood pressure reaches 140 mm Hg or higher and/or diastolic blood pressure reaches 90 mm Hg or higher. This change reflects growing evidence that tighter blood pressure control for some individuals during pregnancy may help to reduce the risk of serious complications.

In addition, postpartum care is especially important because high blood pressure can begin or persist after delivery. The guideline urges continued blood pressure monitoring and timely treatment during the postpartum period to help prevent complications. Patients with a history of pregnancy-associated high blood pressure are encouraged to have their blood pressure measured at least annually.

“It is important for people to be aware of the recommended blood pressure goals and understand how healthy lifestyle behaviors and appropriate medication use can help them achieve and maintain optimal blood pressure. Prevention, early detection and management of high blood pressure are critical to long-term heart and brain health, which means longer, healthier lives,” said Jones.