Exercise

Research highlights how lifestyle can overcome genetic obesity risks

A groundbreaking study published in “Cell Metabolism” has illuminated the powerful role of lifestyle modifications in mitigating the genetic predisposition to obesity, revealing new avenues for managing this global health challenge.

Obesity has reached pandemic proportions, exacerbated by inactive lifestyles and the consumption of high-calorie diets. The condition is influenced by both heritable and polygenic factors, with numerous metabolic pathways and over a thousand genetic variants playing roles. Traditionally, it was assumed that one’s genetic risk for obesity was unalterable.

Recent gene-environment studies have hinted that certain lifestyle choices might lessen the influence of specific genes linked to obesity. These studies, however, typically focused only on limited genes and lifestyle factors, leaving a gap in understanding the broader interaction between lifestyle habits and genetic predispositions.

This latest research delved into whether lifestyle changes could indeed counteract genetic risks. The study cohort included 338,600 white British participants from the UK Biobank, refined to 337,554 after excluding those lacking essential data. Researchers calculated a polygenic score (PGS) from a genome-wide association study on body mass index (BMI) specific to individuals of European descent. They also developed a healthy lifestyle score based on five factors: alcohol consumption, sleep duration, sedentary behaviour, diet, and physical activity. The study’s primary focus was on new obesity cases, with existing obesity cases as a secondary focus.

The researchers predicted absolute risks using odds ratios (ORs) and hazard ratios (HRs) for both new and existing obesity, relative to PGS percentile and lifestyle factors. These ratios were derived from Cox proportional hazard and logistic regression models. They also calculated the probability of developing obesity by age 75 and identified new obesity-related morbidities (ORMs) from various health data sources.

Analyses showed that high genetic risk and unhealthy lifestyle habits were each linked to higher obesity risks, both independently and combined. The risk was most pronounced in those with both high genetic predisposition and poor lifestyle habits, with a HR of 3.54 compared to those with low genetic risk and healthy lifestyles.

Interestingly, the median likelihood of obesity by age 75 varied significantly with lifestyle: 2.8% in those with poor lifestyles versus 1.7% in those with healthier choices. This pattern was echoed in the analysis of existing obesity cases.

The study also found significant additive interactions between lifestyle and genetic risk in terms of obesity incidence, with consistent results from multiplicative interaction analysis. Importantly, sedentary behaviour was linked to the highest obesity risk, regardless of genetic background. Conversely, individuals with high genetic risk but who maintained healthy lifestyles had similar ORMs to those with lower genetic risk.

Overall, the study underscores the profound impact of healthy lifestyle choices in reducing the risk of obesity and its related health issues, even among those with a high genetic predisposition. These findings advocate for the promotion of active, health-conscious behaviours across all genetic backgrounds as a critical strategy in combating obesity.

This research not only challenges the fatalistic view of genetic determinism but also highlights the empowering role of personal lifestyle choices in managing one’s health.

Evening workouts best for lowering blood sugar in adults with overweight and obesity

Recent investigations have shown that exercising in the evening can significantly decrease daily blood sugar levels in inactive adults who have overweight or obesity. This finding was reported in a study published in the journal Obesity, the flagship publication of The Obesity Society (TOS).

The study reveals that while the benefits of moderate to vigorous physical activity on glucose homeostasis are well acknowledged for adults at increased risk of insulin resistance, the specific timing that maximises these benefits had not been determined until now.

Professor Jonatan R. Ruiz of the University of Granada, who specialises in physical activity and health within the Faculty of Sport Sciences-Sport and Health University Research Institute (iMUDS), underscored the significance of timing in exercise routines. “Our results highlight the importance of the field of precision exercise prescription. In clinical practice, certified sports and medical personnel should consider the optimal timing of the day to enhance the effectiveness of the exercise and physical activity programmes they prescribe,” stated Ruiz. He led the research alongside predoctoral researcher Antonio Clavero-Jimeno.

The research utilised baseline data from a multi-centre randomised controlled trial carried out in Granada and Pamplona, Spain. The study aimed to examine the impact of time-restricted eating on visceral adipose tissue, body composition, and cardiometabolic risk factors among adults with obesity and overweight.

Involving 186 participants with an average age of 46 years and a body mass index of 32.9 kg/m2, the study monitored physical activity and glucose levels simultaneously over a 14-day period. This was achieved using a triaxial accelerometer and a continuous glucose-monitoring device.

Researchers categorised the volume of physical activity into periods: morning, afternoon, and evening. Activities were assigned to a period if over 50% of exercise was done within those times, with evening defined as 6 p.m. to midnight.

The findings indicated that engaging in more than 50% of daily moderate to vigorous physical activity in the evening led to lower glucose levels throughout the day and night, and these benefits were particularly pronounced in individuals with impaired glucose regulation. This pattern was consistent across both genders.

Renee J. Rogers, PhD, a senior scientist at the University of Kansas Medical Center, highlighted the implications for tailored exercise advice. “As the field moves towards individualised exercise prescriptions for different chronic conditions, this study now provides additional insights beyond just telling patients to ‘move more,’ but instead to move as often as possible and to prioritise afternoon-to-evening movement when feasible for glucose regulation,” said Rogers, who was not involved in the study.

The study also featured contributions from Manuel Dote-Montero, Jairo H. Migueles, Alba Camacho-Cardenosa from the University of Granada; Maddi Oses, Jon Echarte Medina, Juan M.A. Alcantara, Idoia Labayen from the Public University of Navarre and the Navarra Institute for Health Research (ldiSNA), and Manuel Muñoz-Torres from ibs.GRANADA and the University Hospital San Cecilio Clinic.

Poor muscle health in Individuals with obesity increases risk of early death, study finds

A pivotal study presented at the European Congress on Obesity (ECO) in Venice, Italy, from 12-15 May, 2024, has unveiled a stark correlation between suboptimal muscle health and an increased risk of premature death among individuals with obesity.

The research, carried out by a Swedish team on a UK cohort, established that individuals with compromised muscle composition were three times more likely to die during the study period compared to those with healthier muscle conditions. Dr. Jennifer Linge of AMRA Medical in Linköping, Sweden, spearheaded the research and shared compelling insights. “By examining muscle composition, we can predict which individuals with obesity are most at risk of early death in the forthcoming years,” Dr. Linge explained, highlighting the potential of muscle analysis as a predictive tool for mortality.

In recent years, weight loss has become a central strategy in managing chronic conditions such as type 2 diabetes and cardiovascular diseases. With pharmaceutical advancements, patients are now achieving significant weight reductions, previously possible only through surgical interventions. However, this brings to light concerns about possible detrimental effects on muscle health, including severe muscle mass loss and reduced mobility.

Dr. Linge elaborated on the complexities of muscle health in individuals with obesity, “Although individuals with obesity typically have more muscle mass, their muscles tend to be comparatively weaker. They also exhibit lower muscle quality, as well as reduced mobility and function.” She emphasised the importance of thorough muscle composition assessments, which consider both muscle quantity and quality, in evaluating the safety of rapid weight loss treatments, particularly for more vulnerable patients, such as those with sarcopenic obesity or advanced age.

The study also highlighted a critical gap in research concerning muscle health among populations with obesity, despite existing evidence from MRI studies that link poor muscle health with reduced functional performance, increased illness, and higher mortality rates in individuals with non-alcoholic fatty liver disease (NAFLD) and the general populace.

To address this, Dr. Linge and her colleagues utilised the AMRA Researcher software to analyse MRI scans from 56,109 participants in the UK Biobank study. They measured muscle volume and muscle fat, establishing a personalised muscle volume z-score to benchmark each individual’s muscle volume against the norm for their sex and body size.

From the extensive dataset, 9,840 participants—half of whom were men, with an average age of 64.4 years and a mean BMI of 33.5 kg/m²—were identified as having obesity and had comprehensive data on muscle composition. Of these, 2,001 (20.3%) exhibited adverse muscle composition. Over an average follow-up of 3.9 years, 174 participants died, predominantly from ischemic and hypertensive diseases.

The study findings indicated that neither low muscle volume z-score nor high muscle fat alone significantly influenced mortality risk. However, adverse muscle composition—characterised by both low muscle volume and high muscle fat—was strongly associated with a tripled risk of death during the follow-up period. This association persisted even when adjustments were made for factors like strength (hand grip), other diseases (cancer, type 2 diabetes, and coronary heart disease), and lifestyle factors (smoking, alcohol consumption, and physical activity), revealing a 70% increased risk of early death.

Sex, age, type 2 diabetes, and smoking were also noted as factors increasing the risk of premature death.

Dr. Linge concluded, “These results underscore the paramount importance of maintaining muscle health in people with obesity. It is crucial to determine whether drugs that achieve significant or rapid weight loss are inadvertently causing excessive muscle loss or worsening muscle quality, to ensure safer treatment approaches for obesity, particularly for those at greater risk.” This call to action not only emphasises the significance of maintaining muscle health but also the necessity of careful evaluation of treatment strategies for obesity.

Study reveals heart damage risks in sedentary children

A recent study has highlighted alarming trends in heart health among children and young adults, revealing that excessive sedentary behaviour, commonly referred to as being a ‘couch potato’, could lead to an enlarged heart. This condition significantly increases the risk of heart attacks, strokes, and premature mortality.

Researchers have identified that sedentary habits account for up to 40% of the total increase in heart size from the ages of 17 to 24. The study also discovered that limited physical movement contributes to the enlargement of teenagers’ hearts independently of other contributing risk factors such as obesity or hypertension.

Andrew Agbaje, an associate professor of clinical epidemiology and child health at the University of Eastern Finland in Kuopio, referred to childhood and teenage sedentary behaviour as a “ticking time bomb.” Agbaje, in a recent press release, stressed the severity of the health threats posed by inactivity during youth. “There is growing evidence that childhood sedentariness is a serious health threat that warrants urgent attention,” he stated.

Conversely, the study noted that children who participate in regular light physical activity can mitigate the risk of heart enlargement significantly. Such activities have been found to reduce the increase in heart mass by 49%. “Engaging in three to four hours of light physical activity daily is an effective countermeasure to sedentary habits,” Agbaje explained.

Activities beneficial for cardiovascular health include playing outdoor games, walking pets, running errands on foot, cycling to local destinations, strolling in parks, gardening, and playing casual sports like basketball, soccer, and frisbee.

The study also observed that children who engage in more intense workout routines might see an approximate 5% increase in heart mass, which is attributed to strengthening of the heart muscle rather than harmful enlargement.

This research followed nearly 1,700 participants in the UK from the age of 11 to 24. To monitor their physical activity levels, participants wore motion-tracking devices around their waists for periods ranging from four to seven days at ages 11, 15, and 24. Initial data showed that children spent an average of six hours a day in sedentary activities, which alarmingly increased to nine hours by young adulthood.

The study further incorporated echocardiograms taken at ages 17 and 24 to assess heart structure and function, revealing significant insights into the impact of lifestyle on cardiac health.

Published on the 7th of May, 2024 in the European Journal of Preventive Cardiology, this study underscores the critical need for integrating more physical activity into the daily routines of young people to combat the adverse effects of a sedentary lifestyle on heart health.

Google’s vision for digital health: Leveraging AI for groundbreaking personal health insights

Google Health is setting a new benchmark in healthcare technology with its ambitious roadmap for 2024, focusing on the transformative potential of generative AI in enhancing clinical decision-making, understanding laboratory and imaging data, detecting diseases at an early stage, and offering customised health coaching based on user Fitbit data.

During the annual The Check Up event at Google’s Pier 57 office in Manhattan, key executives from the tech behemoth unveiled significant progress and updates on a range of leading-edge AI initiatives. The spotlight was on refining the Gemini model for healthcare applications, creating a bespoke health-centric large language model (LLM) for the Fitbit app to provide tailored wellness and health features, pioneering AI models for early disease detection, and exploring how generative AI can facilitate medical reasoning and support in clinical dialogues.

At last year’s Check Up event, Google introduced Med-PaLM 2, an LLM specifically tuned for healthcare. Following this, in December, Google announced MedLM, a suite of foundational models for healthcare built upon Med-PaLM 2, which has been made more widely accessible via the Google Cloud’s Vertex AI platform.

Various healthcare organisations are currently piloting Google’s LLM models to devise solutions across a spectrum of applications, such as enhancing clinical documentation and optimising nurse handovers.

Karen DeSalvo, M.D., Google’s Chief Health Officer, underscored the pivotal moment AI technology is within the healthcare sector during her address at The Check Up event.

“It’s an exhilarating time to be at Google, where our cutting-edge technology is leveraged to foster better health outcomes. Our mission is to embed AI in a manner that enriches people’s lives through improved health. We aim to achieve this by integrating health-focused solutions into everyday products and services, thereby empowering our partners and communities,” DeSalvo expressed.

DeSalvo shared her vision of a near future where AI empowers healthcare, enhancing the wellbeing of all, rather than a select few. However, she emphasised that AI is to be seen as a tool augmenting the clinician-patient interaction, rather than replacing it.

In collaboration with Google Research, Fitbit is developing a health-specific LLM to provide Fitbit and Pixel device users with a bespoke health coaching experience based on their personal data.

This initiative is set to offer personalised coaching functionalities, such as customised advice and recommendations, tailored to individual health and fitness aspirations. The launch of Fitbit Labs in the autumn marked the beginning of leveraging AI for deeper health insights.

Florence Thng, Director of Product Management at Fitbit, highlighted the collaborative efforts with Google Research and health experts to formulate personalised health LLMs that can interpret health and fitness data to offer customised advice, akin to a personal coach.

Moreover, earlier this year, Google unveiled AMIE (Articulate Medical Intelligence Explorer), an AI research system optimised for diagnostic reasoning and clinical dialogues, built on an LLM.

Greg Corrado, a distinguished scientist and the head of health AI at Google Research, during the event, emphasised the importance of empathy in medicine and how AMIE is designed to reflect this in clinical consultations.

The ambition to harness AI in healthcare is reaching new heights with Google’s ongoing research and development efforts. The Gemini model suite, particularly fine-tuned for the medical field, is demonstrating remarkable capabilities in advanced reasoning and handling complex data across multiple modalities.

The deployment of MedLM for Chest X-ray analysis signifies Google’s commitment to applying AI in practical, impactful ways in medicine, promising to assist healthcare professionals in making more informed decisions and improving patient care outcomes.

This evolving landscape of medical AI at Google points to a future where technology and healthcare intersect more seamlessly, promising a new era of innovation and enhanced care delivery.

Rising bowel cancer rates in UK youth linked to obesity and alcohol consumption

A recent study has highlighted a concerning trend in the United Kingdom: increasing instances of bowel cancer among younger individuals, driven by unhealthy lifestyle choices. This alarming development is primarily attributed to factors such as obesity, excessive alcohol consumption, and a general lack of physical activity.

Traditionally diagnosed in individuals over the age of 50, bowel cancer is now increasingly affecting younger demographics. This shift coincides with a deterioration in lifestyle habits among the youth, including heightened alcohol consumption and reduced physical exercise. The research, published in the ‘Annals of Oncology‘, raises questions about the adequacy of current screening ages and calls for a re-evaluation.

The study also presents worrying findings regarding bowel cancer mortality rates in women. Unlike many other cancers, which are showing a declining death rate, bowel cancer continues to pose a significant threat to women of all ages. The comparative analysis of anticipated death rates in 2024, using 2018 as a baseline, reveals that the UK is experiencing a notably higher increase in these rates compared to other European countries like Italy, Germany, Poland, and Spain.

Specifically, the UK is facing a projected 26% increase in bowel cancer death rates among men and an even more startling 39% rise among women. These figures starkly contrast with those from other European nations, where the increases, though present, are considerably lower.

Researchers have identified a worrying trend in bowel cancer mortality, especially among the 25 to 49 age group, where rates have been climbing since around the year 2000 in both men and women. This is despite an overall decrease in colorectal cancer mortality across all age groups in past decades.

Interestingly, while the overall cancer death rates in the UK are predicted to decline among both sexes, bowel cancer remains a significant exception, particularly for women. The researchers noted that while age-standardised rates (ASRs) for bowel cancer are showing a favourable decrease for men, the same is not true for women.

Professor Carlo La Vecchia, from the University of Milan, emphasises that key contributors to this rise in young people include obesity, overweight, and associated health issues like elevated blood sugar levels and diabetes. He also points out the link between alcohol consumption and early onset bowel cancer. Countries that have seen a reduction in alcohol consumption, such as France and Italy, have not witnessed such pronounced increases in bowel cancer death rates.

Professor La Vecchia also highlights the aggressiveness of early onset bowel cancer, noting its lower survival rates compared to cases diagnosed in older individuals. He urges national governments to adopt policies promoting healthier lifestyles, including increased physical activity and reduced obesity and alcohol consumption. Furthermore, he advocates for the lowering of the age threshold for bowel cancer screening to 45 years.

The World Cancer Research Fund has labelled these findings as “alarming”, acknowledging the increasing exposure of young people to cancer risk factors from an early age. Dr Panagiota Mitrou, the director of research at the WCRF, underscores the importance of addressing these risk factors early on.

In England, bowel cancer screening is currently offered to individuals aged 60 to 74, with plans to expand the programme to those aged 50 to 59. However, there is a call for further improvements in diagnosis, treatment, and survival rates. Former national cancer director, Professor Sir Mike Richards, suggests adjusting the sensitivity threshold for the FIT stool test to enhance early detection.

Responding to these concerns, a spokesperson for the Department of Health and Social Care emphasised the role of the independent UK National Screening Committee in determining the age cohorts for screening, balancing the benefits against potential harms such as overdiagnosis. They also highlighted the government’s commitment to promoting healthier food choices and tackling obesity, acknowledging its significant impact on the NHS and its contribution to a range of serious diseases.

Losing weight through dance could beat conventional workouts

Traditional exercise routines, often recommended for shedding weight, can pose challenges in maintaining enthusiasm and commitment. Their repetitive and solitary nature, coupled with the physical exertion required, can make them less appealing over time.

Contrastingly, dancing emerges as a potent alternative for weight loss, according to recent research findings. Its inherent enjoyment and the opportunity for social engagement it provides set it apart from conventional exercise forms.

A meta-analysis examining 10 studies focusing on dance’s impact on individuals with overweight and obesity revealed significant health benefits. Regular dancers demonstrated marked improvements in body mass index (BMI), waist circumference, body fat percentage, and total fat loss, compared to non-dancers. These findings were published in the journal PLOS ONE.

The studies encompassed a variety of dance styles, including step-aerobic, cheerleading, creative, Zumba, bhangra, traditional, dance video games, square dance, simplified dance, and aerobic fitness dance. The frequency of dance sessions varied, with most participants dancing three times a week, except for square dancers (five times a week) and bhangra dancers (twice a week). Session durations ranged from 40 to 90 minutes, and the studies lasted from four weeks to one year.

Adherence to an exercise program is crucial for its success, and dancing’s entertainment value might significantly enhance this adherence. Dr. Jagdish Khubchandani, a public health professor at New Mexico State University not involved in the study, highlighted the motivational challenges of traditional exercises, often perceived as arduous and demanding in terms of time, physical effort, and financial resources.

Stephanie Escobedo, founder of Through the Body, a dance and fitness company, and not a participant in the research, echoed this sentiment. She emphasised the importance of finding an enjoyable exercise form for consistent engagement.

Dr. Menka Gupta, a functional medicine doctor at NutraNourish, remarked on the dance’s dual physical and mental health benefits. Beyond improving BMI, dance activities can elevate mood, reduce stress, and enhance sleep quality, thanks to the dopamine release associated with pleasure.

Dr. Khubchandani also referenced studies indicating dancing’s potential to enhance executive function, offering both physical and psychological advantages.

When it comes to choosing the most beneficial dance form, Dr. Gupta advises selecting one that resonates personally, ensuring long-term commitment and consistency. For older individuals or those preferring lower intensity, she recommends ballroom dancing for its social, balance, posture, and cardiovascular benefits.

Dr. Gupta particularly praises Zumba for its mental sharpness benefits, incorporating high-intensity interval training that fosters cognitive skills like decision-making and spatial recognition.

Escobedo supports the health benefits of various dance forms, highlighting ballet for muscle strength, balance, posture, and cardio endurance, and modern/contemporary dance for agility and core strength. She notes that popular cardio dance classes can contribute significantly to weight loss and overall fitness, offering a more enjoyable alternative to routine exercises.

Finally, Dr. Gupta stresses the emotional connection aspect of dance, sharing her personal preference for Zumba and Bollywood dancing, which evoke nostalgic childhood memories and connections.

In summary, dance not only serves as an effective exercise alternative for weight management but also offers diverse physical, mental, and emotional benefits, making it a comprehensive fitness choice.

Excessive school holiday downtime linked to rising health concerns in children

The extended school holidays, a period of relaxation and rest for educators and students alike, may be inadvertently contributing to health issues in children. Recent research highlights a worrying trend of increased weight gain during these leisure times, particularly among children.

In Australia, the prevalence of children and teenagers with overweight or obesity stands at one in four, reflecting a global issue where over 124 million children and adolescents have obesity. These alarming figures have spurred governments, educational institutions, and communities to advocate for enhanced physical activity and healthier eating habits among the younger demographic.

The groundbreaking ‘Life on Holidays‘ study, spearheaded by the University of South Australia’s Alliance for Research in Exercise, Nutrition and Activity team, is the first to explore this phenomenon outside the United States. It specifically examined the impact of holiday periods on children’s fitness levels and body composition.

The study’s findings revealed a concerning pattern: children’s body fat accumulates more rapidly during school holidays than during academic terms. Notably, children in Years 4 and 5 exhibited a decrease in physical activity and an increase in sedentary behaviours during their holidays.

Key observations included children sleeping an average of 12 minutes less, engaging in 12 fewer minutes of physical activity daily, and spending an additional 70 minutes on screens each day during holiday periods. Consequently, there was a marked acceleration in body fat accumulation and a more pronounced decline in aerobic fitness compared to term time.

Professor Tim Olds, lead researcher from UniSA, suggests that promoting physical activities during school holidays could be crucial in combating these negative health trends. He notes that while children and their parents rightly deserve holiday downtime, the lifestyle shift during these periods often negatively impacts children’s health.

“On school holidays, kids are significantly less active than when they’re at school, leading to higher body fat percentages and lower levels of fitness,” Professor Olds remarked. He expressed concern over the rapid rate of weight gain and fitness loss during holidays, pointing out the potential long-term health risks such as cardiovascular disease and Type 2 diabetes.

The study, which spanned two years, focused on children aged 9-10 years and involved over 150 participants. Data were collected at the start and end of Terms 1 and 4 across Grades 4 and 5.

Co-researcher Dr Dot Dumuid highlighted that the unstructured nature of school holidays contributes significantly to these trends. She pointed out that children have unrestricted access to food and are prone to increased screen time due to the lack of structured activities.

Dr Dumuid contrasted this with the structured environment of school days, where meals are planned, and physical education lessons and playtimes are scheduled. She suggested that adopting American-style summer camps and holiday programs could be an effective way to address the issue in Australia. These programs, she noted, have been successful in providing children with physical activities in a more structured setting.

“Summer camps and holiday programs have shown positive results in America and could offer a valuable solution during Australian holidays,” Dr Dumuid said. She emphasised the need for a balance between leisure and physical activity, questioning the reliance on devices and TV for child care at the expense of children’s health.

The study underlines the importance of finding a healthy balance between relaxation and physical activity during school holidays. As societies grapple with increasing rates of childhood obesity and associated health problems, initiatives like summer camps and structured holiday programs could play a pivotal role in ensuring the health and well-being of the younger generation.

Study confirms light exercise effectively counters childhood obesity

Childhood obesity, a growing concern worldwide, might have a surprisingly straightforward solution: light exercise. Recent research led by an international team of scientists from the Universities of Exeter, Eastern Finland, Bristol, and Colorado, underscores the profound impact of light physical activity in combating the rise of obesity in children.

Drawing from the University of Bristol’s Children of the 90s study, the research tracked 6,059 children (53% female) from age 11 to 24. Amid global reports revealing a worrying trend of inactivity among adolescents — with over 80% failing to meet the World Health Organization’s guidelines for daily physical activity — the study presents an urgent narrative. The lack of exercise is anticipated to contribute to 500 million new cases of noncommunicable diseases by 2030, costing an estimated $23 million annually.

What’s striking about the study is the revelation that light physical activity, rather than moderate-to-vigorous exertion, plays a crucial role in reducing fat mass gain in youth. Dr. Andrew Agbaje of the University of Exeter, a key contributor to the study, emphasises the overlooked benefits of light physical activities like walking, household chores, and leisurely swimming. He suggests shifting public health messages from an emphasis on 60 minutes of moderate-to-vigorous activity to encouraging at least three hours of light activity daily.

Participants were observed over 13 years, with physical activity levels and health markers meticulously monitored using waist-worn accelerometers and dual-energy X-ray absorptiometry. The results were startling: each additional minute of sedentary behaviour correlated with a 1.3-gram increase in total body fat mass. In contrast, each minute of light physical activity corresponded to a 3.6-gram decrease in total body fat mass, amounting to a significant reduction of 950 grams to 1.5 kilograms over the study period.

In comparison, moderate-to-vigorous physical activity showed a minimal effect, reducing total body fat mass by only about 0.7 to 1.7 percent. This finding challenges the prevailing public health guidelines, which predominantly advocate for higher-intensity exercise.
The study, published in Nature Communications, calls for a reevaluation of health guidelines and policy statements, urging public health experts, policymakers, and parents alike to promote light physical activity as a key strategy in preventing childhood obesity. As Dr. Agbaje concludes, sustaining light physical activity can be the much-needed antidote to the detrimental effects of a sedentary lifestyle in young populations.

Exercise hormone irisin emerges as potential therapeutic agent in Alzheimer’s research

In the relentless pursuit to find effective treatments for Alzheimer’s disease, researchers have spotlighted a potential new ally: the hormone irisin, which is generated during physical exercise. This revelation brings a beacon of hope, suggesting a potential new frontier in Alzheimer’s therapy.

According to a recent study carried out by a team at the Massachusetts General Hospital in Boston, the elevation of irisin levels, encouraged through physical exercise, showcases promising results in reducing the plaque and tau tangles that are trademarks of Alzheimer’s disease. The role of irisin had been previously linked to the regulation of glucose and lipid metabolism in adipose tissue and the acceleration of the conversion of white fat tissue to brown, a process that augments energy expenditure.

Before delving deeper into irisin’s impact on Alzheimer’s, the team had pioneered the development of 3D human cell culture models of the disease. These models played a pivotal role in understanding how irisin interacts with amyloid-beta, a significant player in the Alzheimer’s landscape, present in the brain.

Previous studies on murine models had affirmed the beneficial effects of physical exercise in diminishing amyloid-beta accumulations, albeit without understanding the precise mechanism. The fresh insights gleaned from this study illuminated that irisin’s influence in this context is closely tied to the enhancement of an enzyme known as neprilysin, which is proficient in degrading amyloid-beta.

Se Hoon Choi, one of the study’s authors, illuminated that treating with irisin led to a “remarkable reduction of amyloid-beta pathology,” an effect steered by the bolstered activity of neprilysin, which is secreted in higher quantities by brain cells called astrocytes, in response to irisin.

Notably, the researchers managed to pinpoint the pathway that prompts cells to amplify neprilysin levels, opening avenues for further exploration and therapy development. The endeavour now stood grounded on a robust foundation of understanding how irisin, once introduced into the bloodstream, can navigate its way to the brain, showcasing its potential utility as a therapeutic agent.

Furthermore, senior author Rudolph Tanzi noted that irisin could be the principal orchestrator behind exercise-induced escalations in neprilysin levels that are instrumental in alleviating the amyloid-beta burden in the brain. Tanzi underscored the significant implications of these findings, propelling irisin to the centre stage as a promising target for preventive and therapeutic strategies against Alzheimer’s disease.
This groundbreaking study, published in the renowned journal Neuron on September 8 2023, brings to light irisin’s pivotal role as a mediator, leveraging the natural, exercise-induced hormone to forge a path towards revolutionary Alzheimer’s treatments. It brings us a step closer to harnessing the potential of physical exercise at a molecular level in battling the devastating impacts of Alzheimer’s, thus offering a new ray of hope in medical science’s quest to conquer this debilitating disease.