Posted on Patient Talk

Eating high-processed foods impacts muscle quality

Axial T1-weighted bilateral thigh MR images

Caption

CreditRadiological Society of North Aurora (RSNA) and Zehra Akkaya, M.D.

A diet high in ultra-processed foods is associated with higher amounts of fat stored inside thigh muscles, regardless of the amount of calories consumed or level of physical activity, . Higher intramuscular fat in the thigh could also increase the risk for knee osteoarthritis.

The incorporation of natural and minimally processed ingredients in modern diets has declined, often being replaced by ingredients that are industrially processed, artificially flavoured, coloured, or chemically altered.

Foods such as breakfast cereals, margarine, spreads, packaged snacks, hot dogs, soft drinks, energy drinks, candies, desserts, frozen pizzas, ready-to-eat meals, and mass-produced packaged bread and buns are highly processed and contain synthesized ingredients.

These ultra-processed foods usually have longer shelf lives and are highly appealing. They are convenient and contain a combination of sugar, fat, salt, and carbohydrates that affect the brain’s reward system, making it hard to stop eating.

For the study, researchers assessed the association between ultra-processed food intake and intramuscular fat in the thigh.

“The novelty of this study is that it investigates the impact of diet quality, specifically the role of ultra-processed foods concerning intramuscular fat in the thigh muscles assessed by MRI,” said author Zehra Akkaya, M.D., researcher and former Fulbright Scholar in the Department of Radiology and Biomedical Imaging at the University of California, San Francisco. “This is the first imaging study looking into the relationship between MRI-based skeletal muscle quality and diet quality.”

For the study, researchers analyzed data from 666 individuals who participated in the Osteoarthritis Initiative but were not yet affected by osteoarthritis based on imaging. The Osteoarthritis Initiative is a nationwide research study sponsored by the National Institutes of Health that helps researchers better understand how to prevent and treat knee osteoarthritis.

“Research from our group and others has previously shown that quantitative and functional decline in thigh muscles is potentially associated with onset and progression of knee osteoarthritis,” Dr. Akkaya said. “On MRI images, this decline can be seen as fatty degeneration of the muscle, where streaks of fat replace muscle fibres.”

The average age of the 666 individuals (455 men, 211 women) was 60. On average, participants were overweight, with a body mass index (BMI) of 27. Approximately 40% of the foods they ate in the past year were ultra-processed.  

The researchers found that the more ultra-processed foods people consumed, the more intramuscular fat they had in their thigh muscles, regardless of energy (caloric) intake.

“In an adult population at risk for but without knee or hip osteoarthritis, consuming ultra-processed foods is linked to increased fat within the thigh muscles,” Dr Akkaya said. “These findings held regardless of dietary energy content, BMI, sociodemographic factors or physical activity levels.”

Dr. Akkaya noted that targeting modifiable lifestyle factors—mainly preventing obesity via a healthy, balanced diet and adequate exercise—has been the mainstay of initial management for knee osteoarthritis.

“Osteoarthritis is an increasingly prevalent and costly global health issue. It is the largest contributor to non-cancer related health care costs in the U.S. and around the world,” Dr. Akkaya said. “Since this condition is highly linked to obesity and unhealthy lifestyle choices, there are potential avenues for lifestyle modification and disease management.”

Posted on Diabetes, Diet

Eating dark chocolate linked with reduced risk of type 2 diabetes

Study participants who consumed at least five servings of any chocolate per week showed a 10% lower risk of type 2 diabetes (T2D) compared to those who rarely or never ate chocolate. Dark chocolate had an even bigger impact: Participants who consumed at least five servings of this chocolate per week showed a 21% lower risk of T2D.
Participants in the study who ate at least five servings of any chocolate per week had a 10% lower risk of developing type 2 diabetes (T2D) compared to those who rarely or never consumed chocolate. Dark chocolate had an even more significant effect; participants who drank at least five servings of dark chocolate per week experienced a 21% lower risk of T2D.

“Our research indicates that not all chocolate is the same,” said Binkai Liu, the lead author and a doctoral student in the Department of Nutrition. “For chocolate lovers, this reminds them that small choices, such as dark chocolate instead of milk chocolate, can positively impact their health.”

The existing research on chocolate and T2D shows inconsistent findings, with few studies differentiating between chocolate types, specifically dark and milk chocolate.

The researchers aimed to address a gap in knowledge by utilizing data from the Nurses’ Health Studies I and II, as well as the Health Professionals Follow-up Study. Over more than 30 years, 192,000 adult participants who were free of diabetes at the beginning of the study reported their dietary habits, including chocolate consumption, alongside updates on their diabetes status and body weight. By the end of the study, nearly 19,000 participants had reported a diagnosis of type 2 diabetes (T2D). Among the almost 112,000 participants who specifically reported their intake of dark and milk chocolate, around 5,000 were diagnosed with T2D.

The study found that participants who consumed at least five ounces of any type of chocolate per week had a 10% lower risk of developing type 2 diabetes (T2D) than those who never or rarely consumed chocolate. Dark chocolate had an even more significant impact: participants who ate at least five servings of dark chocolate each week showed a 21% lower risk of T2D. Additionally, the researchers observed a 3% reduction in risk for every serving of dark chocolate consumed weekly. In contrast, consumption of milk chocolate was not linked to a reduced risk of T2D. Moreover, increased intake of milk chocolate—unlike dark chocolate—was associated with long-term weight gain, which can contribute to the development of T2D.

“We were surprised to find a clear distinction between the effects of dark and milk chocolate on diabetes risk and long-term weight management,” said Qi Sun, the corresponding author and an associate professor in the Departments of Nutrition and Epidemiology. “Although dark and milk chocolate contain similar levels of calories and saturated fat, it seems that the rich polyphenols in dark chocolate may counteract the negative effects of saturated fat and sugar on weight gain and diabetes. This intriguing difference warrants further exploration.”

Posted on Autism

Key breakthrough in autism research : pivotal role of condensates demonstrated

IRB Barcelona team

A study by IRB Barcelona unveils how the lack of a fraction of the CPEB4 protein causes a decrease in the expression of genes crucial for neuronal development. Credit IRB Barcelona

Autism is a neurodevelopmental disorder characterized by challenges in communication and social behaviour. About 20% of cases are linked to a specific genetic mutation, while the origin of the remaining 80%, referred to as idiopathic autism, remains unknown.

A team of scientists led by Drs. Raúl Méndez and Xavier Salvatella at the Institute for Research in Biomedicine (IRB Barcelona), has discovered a molecular mechanism that explains why certain alterations in the neuronal protein CPEB4 are linked to idiopathic autism.

The study builds upon previous research published in 2018, which identified CPEB4 as an essential protein in regulating neuronal proteins associated with autism. In that earlier study, researchers found that individuals with autism were missing a specific neuronal microexon, a tiny segment of genetic material vital for proper protein function in neurons. The new findings published in the journal Nature highlight the significance of this tiny fragment in neuronal activity, as it allows CPEB4 to form and disassemble protein condensates effectively.

“This study offers new insights into how minor modifications in proteins that regulate gene expression can significantly influence neuronal development. This discovery opens up new avenues for exploring future therapies,” explains Dr Méndez, an ICREA researcher and head of the Translational Control of Cell Cycle and Differentiation laboratory at IRB Barcelona.

Molecular condensates and gene regulation

The region of the CPEB4 protein that holds the segment lacks a well-defined three-dimensional structure. Proteins with disordered regions can form condensates, like tiny droplets within the cell where molecules, such as messenger RNAs (mRNAs) that code for other proteins involved in neuronal function, are stored in a silenced state. These condensates can assemble and disassemble in response to cellular signals, enabling dynamic regulation of gene expression.

“In this study, we have discovered that this neuronal microexon is essential for maintaining the stability and dynamics of the condensates formed by CPEB4 in neurons. Without the microexon, these condensates become less dynamic and can aggregate into solid forms that do not function properly,” says Dr Salvatella, an ICREA researcher and head of the Laboratory of Molecular Biophysics at IRB Barcelona.

This lack of dynamism prevents the mRNAs stored in these condensates from being released when neurons are stimulated, leading to decreased production of proteins essential for neuronal development and function. Among these mRNA molecules are many genes previously linked to autism.

Implications for neuronal development

Proper regulation of these genes is essential during brain development. If these CPEB4 condensates do not function correctly due to the absence of the neuronal micro exon, disruptions of neuronal development can occur, manifesting as symptoms of autism. The described mechanism also helps to explain the complexity and heterogeneous nature of idiopathic autism, as this spectrum includes multiple manifestations and varying degrees of severity.

“Our results suggest that even small decreases in the percentage of microexon inclusion can have significant effects. This would explain why some individuals without a gene mutation develop idiopathic autism,” explain Drs: Carla Garcia-Cabau and Anna Bartomeu, IRB Barcelona researchers and first authors of the study.

The concept proposed in this study of gene regulation in neurons through the formation of condensates may also have implications for ageing. Over time, these condensates lose their plasticity, meaning their capacity to assemble and disassemble, which could impair proper neuronal function and promote the development of neurodegenerative diseases.

Possible avenues for future therapies

One of the study’s promising findings is that micro exon 4 appears to work “in trans,” which means that it might be possible to introduce this small sequence of amino acids into cells to partially restore CPEB4 function and potentially reverse the symptoms.

“Although we’re still in exploratory stages, this discovery is promising and points to a potential therapeutic approach that could restore CPEB4 function,” says Dr. Méndez. The researchers emphasise that this finding still requires extensive experimental testing, such as studies in animal models and overcoming multiple technical barriers.

Posted on Cardiovascular disease, Exercise, Women's Health

Small daily bursts of vigorous incidental activity could almost cut cardiovascular risk in middle-aged women.

Tiny, daily bursts of vigorous incidental physical activity could almost halve cardiovascular risk in middle-aged women

Just four minutes of vigorous daily physical activity significantly lowers the risk of heart attacks and heart failure in middle-aged women.

Woman walking upstairs Credit Shutterstock

Research from the University of Sydney reveals that an average of just four minutes of incidental vigorous physical activity each day could nearly reduce the risk of major cardiovascular events, such as heart attacks, by half for middle-aged women who do not participate in structured exercise.

“A study led by Professor Emmanuel Stamatakis, Director of the Mackenzie Wearable Hub at the Charles Perkins Centre and the Faculty of Medicine and Health, found that engaging in at least 1.5 minutes to an average of 4 minutes of vigorous physical activity each day—completed in short bursts of up to 1 minute—was linked to improved cardiovascular health outcomes in middle-aged women who do not participate in structured exercise.”

High-intensity physical activity incorporated into a daily routine is “vigorous intermittent lifestyle physical activity” (VILPA). Longer sessions of VILPA are associated with a significantly lower risk of cardiovascular disease. Researchers suggest that since less than 20 per cent of middle-aged and older adults participate in regular structured exercise, engaging in VILPA could be a beneficial alternative.

“Adopting short bursts of vigorous physical activity as a regular habit could be a beneficial option for women who may not enjoy structured exercise or are unable to engage in it for various reasons. To start, this can be as simple as incorporating a few minutes of activities throughout the day such as climbing stairs, carrying groceries, walking uphill, playing tag with a child or pet, or engaging in power walking,” said Professor Stamatakis.

The study analyzed data from 22,368 participants, consisting of 13,018 women and 9,350 men aged 40 to 79, who reported not engaging in regular structured exercise. This data was collected from the UK Biobank, where participants wore physical activity trackers nearly 24 hours a day for a week, between 2013 and 2015.

Cardiovascular health was monitored through hospital and mortality records, tracking major adverse cardiovascular events (MACE), such as heart attack, stroke, and heart failure, until November 2022. 

After accounting for factors such as lifestyle, socioeconomic status, cardiovascular health, co-existing conditions, and ethnicity, the researchers found that women who engaged in more vigorous intermittent lifestyle physical activity (VILPA) had a lower risk of experiencing major cardiovascular events. Specifically, women who averaged just 3.4 minutes of VILPA daily were 45 percent less likely to encounter a major cardiovascular event. Additionally, they were 51 per cent less likely to suffer a heart attack and 67 per cent less likely to develop heart failure compared to women who did not engage in any VILPA.

Even when daily VILPA levels were lower than 3.4 minutes, they were still linked to lower cardiovascular event risk. A minimum of 1.2 to 1.6 minutes of VILPA per day was associated with a 30 per cent lower risk of total major cardiovascular events, a 33 per cent lower risk of heart attack, and a 40 per cent lower risk of heart failure. 

However, men reaped fewer benefits from tiny bursts of VILPA. Those who averaged 5.6 minutes daily were only 16 per cent less likely to experience a major cardiovascular event compared with men who did none. A minimum of 2.3 minutes per day was associated with only an 11 per cent risk reduction. 

Professor Stamatakis said more testing was needed to understand how VILPA may improve cardiovascular health.  

“To date, it hasn’t been clear whether short bursts of VILPA lower the risk of specific types of cardiovascular events, like heart attack or stroke. We aimed to identify minimum daily thresholds and feasible amounts for testing in community programs and future trials,” he said. 

“Importantly, the beneficial associations we observed were in women who committed to short bursts of VILPA almost daily. This highlights the importance of habit formation, which is not always easy. VILPA should not be seen as a quick fix—there are no magic bullets for health. But our results show that even a little bit higher intensity activity can help and might be just the thing to help people develop a regular physical activity – or even exercise – habit,” he said. 

Posted on Diabetes

High blood sugar in healthy adults linked to lower brain activity

New research shows combined use of sodium glucose co-transporter 2 inhibitors (SGLT2is) and glucagon-like peptide-1 receptor agonists (GLP1-RAs) is likely to offer additional protection against heart and kidney disease in patients with diabetes

A recent study found that high blood sugar may negatively affect brain health even in individuals who do not have diabetes. Although the relationship between blood sugar levels and brain health is well established in those with diabetes, this study is the first to investigate this link in people without the condition.

“Our findings indicate that individuals who do not have a diabetes diagnosis may still have elevated blood sugar levels that could negatively affect their brain health,” said Dr Jean Chen, the senior author of the study and a Senior Scientist at the Rotman Research Institute. . “Blood sugar levels exist on a spectrum; they cannot simply be categorized as healthy or unhealthy.”

The study, “Associations Among Glycemic Control, Heart Rate Variability, and Autonomic Brain Function in Healthy Individuals: Age—and Sex-Related Differences,” was recently published in the journal Neurobiology of Aging. It examined 146 healthy adults aged 18 and older. Researchers analyzed each individual’s blood sugar levels, brain activity through magnetic resonance imaging (MRI) scans, and heart rate variability using electrocardiogram (ECG) readings.

“The findings emphasize the importance of managing blood sugar through a healthy diet and regular exercise, as this benefits not just your body but also your brain,” said Dr. Chen, who is Canada Research Chair in Neuroimaging of Aging and a Professor of Biomedical Physics at the University of Toronto. “Additionally, it’s crucial to have regular checkups and collaborate with a healthcare provider, especially if you have been diagnosed with pre-diabetes.”

Main study findings

  • Higher blood sugar was associated with decreased connections in brain networks. These networks play a crucial role in all aspects of cognition, including memory, attention, and emotion regulation.
  • The effect was more substantial in older adults, but it was present across all ages; older adults generally had higher blood sugar than younger adults.
  • The effect was also stronger in women than in men.
  • In addition, there was a link between higher blood sugar and lower heart rate variability – the beat-to-beat change in an individual’s heart rate. Previous research indicates that higher heart rate variability is associated with better brain health.

In future work, the researchers could investigate how to improve brain function by changing heart-rate variability. Heart rate variability is an easier target for intervention than blood sugar, especially in nondiabetic individuals.