Sigma Nutrition Radio

Contemporary society is witnessing a growing interest in, and embracing of, plant-based diets. Numerous athletes are now gravitating towards such dietary choices, motivated by concerns for health, performance or ethics. Consequently, coaches, nutritionists, and other fitness experts find themselves increasingly tasked with guiding athletes who adhere to plant-based diets. For coaches and trainers, understanding the possible impacts of these dietary preferences on athletes' objectives is paramount, as is devising dietary plans that optimize their performance. This episode discusses the scientific and practical aspects of supporting athletes who have adopted a vegetarian lifestyle and diet. Links: Subscribe to Sigma Nutrition Premium Go to episode page - See related episodes Subscribe to Sigma's email newsletter

The Food Frequency Questionnaire (FFQ) stands as a cornerstone in nutritional research, offering valuable insights into dietary patterns and habits over a specified period. Despite its widespread use and established utility, the FFQ has not been immune to criticism, much of which arises from a misunderstanding of its purpose and inherent limitations. At its core, the FFQ is designed to assess the frequency and quantity of food consumption, aiming to capture long-term dietary behaviors rather than precise intake levels. Researchers employ it to investigate relationships between diet and various health outcomes, such as chronic diseases or nutritional deficiencies. However, critics argue that its reliance on self-reported data introduces biases and inaccuracies, leading to potential misestimation of nutrient intake. Additionally, some detractors question the FFQ's ability to capture sporadic or infrequent dietary choices accurately. Yet, it's crucial to recognize that the FFQ serves a specific purpose within the realm of nutrition research. While there are no doubt limitations, its strength lies in its ability to capture habitual dietary behaviors over an extended period. Moreover, researchers employ various strategies, such as validation studies and data adjustment techniques, to enhance the FFQ's reliability and validity. In this episode, world-leading nutrition epidemiologist Dr. Deirdre Tobias discusses the development of the FFQ, the key concepts that are crucial to understand, common criticisms of the FFQ, and how we should evaluate the utility of this tool. Links: Go to episode page (guest biography, links, etc.) Subscribe to Sigma Nutrition Premium Interested in improving your ability to read nutrition research? Take a look at our course Applied Nutrition Literacy Join the Sigma Nutrition newsletter

Links: Subscribe to Premium (15% off this week!) Download detailed study notes and episode transcript Go to episode page About This Episode: "Personalized nutrition" has been promoted as an approach that will improve people's health by prescribing them specific dietary recommendations based on their own genetic and phenotypic data. The premise is that given we each respond differently to foods, having general dietary recommendations may be doing many people a disservice. And by using an array of personal data, it is now possible to give unique diets that improve health. The early and interesting findings of research in this area was met with much fanfare, and indeed, many companies are now offering commercial direct-to-consumer services based on genetic and physiological testing, followed by "personalized" dietary prescription. Such testing may include genetic tests, microbiome testing, glucose monitoring data, and more. This data is then fed into machine learning algorithms to prescribe dietary recommendations. However, do the marketing claims match the current evidence? Does the "proof" it works that is often cited, actually back up the claims? Do personalized nutrition diets actually lead to improved health outcomes over generic, conventional dietary recommendations? Do personalized nutrition diets lead to better outcomes than standard dietetic/nutrition practice? To answer these questions, we go through the main studies cited in favor of personalized nutrition being superior to typical dietary advice, and see if they indeed support the claims. So is personalized nutrition superior to standard dietary advice? Let's find out… Note: This was originally a Premium-exclusive episode. If you'd like to get more episodes like this, subscribe to Sigma Nutrition Premium.

The relationship between coffee and health is complex, encompassing areas like blood lipids, cardiovascular disease, neurodegenerative diseases, anxiety, and depression. Coffee has an interesting nutrient profile and contains diverse bioactive compounds that influence metabolism. Coffee has a potential impact on cardiovascular disease risk, with mechanisms that highlight potential benefits and some concerns. There may be an impact on blood pressure and blood lipid, but there are important nuances to this. Some research suggests that moderate intake may protect against neurodegenerative diseases like Alzheimer's and Parkinson's, with some mechanisms proposed for the observation. Coffee's effects on anxiety, depression, and sleep are common talking points and worthy of addressing. The context of the consumption and the individual in question will dictate the likely effects. Ultimately, coffee's effects on health are influenced by various factors, warranting personalized approaches to consumption. In this episode, Simon Hill puts some questions to Danny Lennon about the impact of coffee on our health. Links: Go to episode page Subscribe to Sigma Nutrition Premium See Sigma's recommended resources Join the Sigma email list Simon's website: The Proof

Links: Go to episode page Subscribe to Premium Join the Sigma email list Go to our recommended resources About This Episode: Have you ever wondered how exercise affects our appetite and energy intake? While we know that single bouts of exercise can create a short-term energy deficit, do they also influence our hunger levels? And what about long-term exercise training? Could it modify our appetite in ways that help us better control our weight? Recent research suggests that exercise may indeed play a role in appetite regulation. Could exercise modify the subjective and homeostatic mediators of appetite in ways that enhance our feelings of fullness after a meal? One of the most fascinating aspects of this research is the variability in responses between individuals. Why do some people experience changes in appetite and energy intake after exercise, while others don't? Could factors like adiposity, sex, or habitual physical activity levels play a role? In this episode, Dr. James Dorling of the University of Glasgow helps us delve into the evidence surrounding how factors like adiposity, sex, and habitual physical activity modulate our responses to exercise in terms of appetite, energy intake, and appetite-related hormone responses. About The Guest: Dr. James Dorling is a lecturer in Human Nutrition at the University of Glasgow. Dr. Dorling's research is broadly focused on three areas: (1) the impact of nutrition and physical activity interventions on obesity-related endpoints and biomarkers of aging; (2) the regulators of appetite and eating behaviours; and (3) the changes in appetite and eating behaviours in response to health interventions. During his PhD, he studied the effects of acute exercise and obesity-related single nucleotide polymorphisms on appetite and appetite-related hormones. Following this, Dr. Dorling joined Pennington Biomedical Research Center where he worked as a postdoctoral researcher. His postdoctoral research principally focussed on the influence of calorie restriction and physical activity on weight, markers of aging, and eating behaviours.

In a world flooded with claims, advice, and recommendations on how to extend our lifespan, the buzz around various diet approaches, supplement regimens, and lifestyle hacks is deafening. But amidst the noise, one must pause to ponder: Are these claims rooted in science? And perhaps more crucially, are we even asking the right questions or pursuing the correct goals in our quest for longevity? Join us in our upcoming podcast episode as Danny delves into these intriguing questions. Rather than getting lost in the sea of trends and fads, Danny offers his insights on the essential inquiries we should be making. Discover how to shift our focus towards the core factors that genuinely enhance our chances of leading longer, healthier lives. Don't miss out on this thought-provoking exploration into the science and philosophy behind longevity. Links: Subscribe to Premium Go to SigmaNutrition.com

Acronyms & Terminology: NHS - National Health Service (UK) CAMHS eating disorder unit - Child & Adolescent Mental Health Service Tier 4 Services - CAMHS services are organized through a tiered system. Tier 4 is the highest on the hierarchy and relates to highly specialized or inpatient services. NG Feed - nasogastric (NG) tubes MDT decision - multidisciplinary team (MDT) decision-making CBT-E - Enhanced Cognitive Behaviour Therapy - a "transdiagnostic" treatment for all forms of eating disorder including anorexia nervosa, bulimia nervosa, binge eating disorder and other similar states​. ARFID - Avoidant/restrictive food intake disorder (ARFID) is a feeding or eating disorder in which people avoid eating certain foods, or restrict their diets to the point it ultimately results in nutritional deficiencies. SSCM - Specialist Supportive Clinical Management (SSCM) is a psychotherapy comprising a clinical management focus addressing anorexia nervosa (AN) symptoms and a supportive therapy component. Links: Subscribe to Premium Go to episode page About This Episode: When exploring the landscape of eating disorder treatment and research, several crucial topics emerge, each shedding light on different aspects of this complex field. Firstly, the practice of nasogastric feeding under restraint raises ethical questions and considerations. How do healthcare professionals navigate the balance between ensuring adequate nutrition and respecting the autonomy and dignity of patients? What are the potential implications and risks associated with this practice? Progress in understanding and treating eating disorders has evolved significantly over the years, yet challenges persist in translating research findings into effective clinical practice. How can advancements in genetics, neurobiology, and psychology inform more personalized and holistic treatment approaches? What barriers hinder the implementation of evidence-based practices within healthcare settings? An essential aspect of eating disorder treatment is understanding what "recovery" truly means. Beyond weight restoration, what factors contribute to a meaningful and sustainable recovery journey? How can healthcare professionals support individuals in achieving their unique goals and aspirations for recovery? Improving services and introducing better treatment options requires a nuanced understanding of the complexities inherent in eating disorders. How can healthcare systems prioritize patient-centered care and tailor interventions to meet the diverse needs of individuals affected by eating disorders? What strategies can be employed to address systemic challenges and foster positive change within healthcare settings? In addressing these questions and navigating the complexities of eating disorder treatment and research, expertise and insights from seasoned professionals are invaluable. In this episode Helen West, an Advanced Specialist Eating Disorders Dietitian with over 12 years of clinical experience, discusses her experience and understanding of these areas. With her extensive background and expertise, Helen offers valuable perspectives in tackling these critical topics within the realm of eating disorder treatment and research.

Links: Course: Applied Nutrition Literacy Subscribe to Premium Go to episode page (study links, bio, etc.) About This Episode: There has been much debate about the role of nutritional reductionism in research. This approach generally aims to study diet's effects by breaking down the intricate web of dietary factors into smaller, more manageable components. But critics have asked does this approach truly capture the full picture of nutrition's influence on our well-being? In an attempt to help answer research questions there has been a proposal for the use of "nutritional geometry", a framework that delves into the multidimensional relationships between nutrients and their effects on organisms. Within this framework, the protein leverage hypothesis emerges, proposing that our bodies prioritize protein intake and adjust food consumption accordingly. But how does this theory fit into the broader spectrum of nutrition science, and what implications does it hold for understanding and managing our diets? Additionally, as aim to do better nutrition research, we are met with philosophical questions that challenge traditional reductionist views. Is it enough to simply dissect foods into their nutrient components, or do we need a more holistic understanding of dietary patterns and their impact on health? In this episode, Prof. David Raubenheimer and Dr. Jonathan Sholl discuss the need to have an approach where science meets philosophy, and where reductionism meets synthesis. And we dive into ideas they have proposed that make a defense of some aspects of reductionism.

Links: Enroll in our new course! Go to episode page Subscribe to Sigma Nutrition Premium About This Episode: Sigma Nutrition is ten years old this week! Over this time, I'm grateful for a wealth of insights garnered from interviews with some of the brightest minds in the field of evidence-based nutrition science. Through these conversations, I've come to understand the critical underpinnings of scientific thinking, the importance of honing our critical appraisal skills, and the crucial distinction between accurate dissemination of information and misleading "half-truths".

Links: COURSE: Applied Nutrition Literacy Episode page About This Episode: Navigating the vast landscape of research literature, particularly in the realm of nutrition science, presents numerous challenges for readers seeking to extract meaningful insights. Before diving into research papers, individuals should have a precise understanding of the specific questions they seek to address. Without this clarity, there is a risk of wasting time on irrelevant studies or misinterpreting findings. Furthermore, the selective approach to sourcing research is crucial. With countless studies available, employing heuristic strategies to filter out irrelevant ones and prioritize those aligned with research goals is essential. Effectively reading nutrition studies requires a nuanced understanding of statistical concepts and methodologies used in various studies. Developing this understanding can be challenging, especially for individuals without a background in statistics or research methodology. How can individuals effectively navigate the vast volume of research literature to find studies relevant to their interests or research objectives? What are some common pitfalls to avoid when reading and interpreting nutrition science research? What role do external influences, such as media coverage or recommendations from experts, play in shaping perceptions of research findings? Are there specific strategies or tools that people can use to streamline their research process and optimize their time spent reading research papers? In this episode, we discuss all these issues. Course syllabus: Applied Nutrition Literacy

Questions Answered in This Episode: [01:22] Do "low-carbers" need less vitamin C? [14.56] If you were to advise a company to establish solid workplace health fundamentals, what would you tell them? [26.20] Which compounds typically found in animal products would be interesting to supplement for health and performance purposes in vegan/vegetarian populations? [40.09] In omega 3 supplementation studies it isn't common to see a baseline measurement of omega 3 index. Why? [44.10] What is your process for preparing for a podcast and choosing topics? [49.53] Based on the current understanding, what is the most ideal diet for people to eat? [55.26] Is there any evidence that otherwise healthy people should be consuming Omega 3 supplements? This is a preview of is one of our Premium-exclusive AMA (ask me anything) episodes, where we answer questions submitted by Premium subscribers. To listen to the full episode, you'll need to be a Premium subscriber and access the episode on the private Premium feed.

Links: Go to episode page Subscribe to Premium See recommended resources Receive the Sigma email newsletter About This Episode: The question of whether dietary fat quality causally affects atherosclerosis risk has been a subject of extensive research and debate within the field of nutrition and cardiovascular health. Atherosclerosis, the build-up of plaque in arteries, is a key factor in the development of cardiovascular diseases, including heart attacks and strokes. Traditionally, dietary fat has been implicated in contributing to atherosclerosis, with a focus on reducing overall fat intake. However, recent studies have shifted the focus towards the quality of dietary fats rather than their quantity. Not all fats are created equal, and researchers are now paying closer attention to the types of fats consumed in the diet. Saturated fats, commonly found in animal products and some tropical oils, have long been associated with increased cholesterol levels and atherosclerosis. On the other hand, unsaturated fats, including monounsaturated and polyunsaturated fats found in olive oil, nuts, and fish, have been linked to potential cardiovascular benefits. Research suggests that replacing saturated fats with unsaturated fats may have a positive impact on blood lipid profiles and reduce the risk of atherosclerosis. Additionally, genetic factors and individual responses to different fats may play a role in how dietary fats impact atherosclerosis risk. In this episode, Dr. Jacob Christensen discusses the research in this area and some conclusions about whether we can say dietary fat quality causally increases atherosclerotic cardiovascular disease (ASCVD) risk. This includes looking at the relationship between low-density lipoprotein (LDL) particles and ASCVD, the link between dietary fat quality and LDL particles, and then finally the relationship between dietary fat quality, LDL particles, and ASCVD. About the Guest: Jacob J. Christensen is a clinical dietitian and researcher at University of Oslo. His research interests include cardiovascular diseases, lipid metabolism, nutrition, genomics and data science.

Links: Go to episode page Subscribe to Premium Join the Sigma mailing list Sigma's Recommended Resources About This Episode: There is a lot of interesting research going on related to plant-derived fatty acids, owing to their potential to help improve health and provide sustainable alternatives to other sources of healthy-promoting fatty acids. In addition to work looking at the long-investigated alpha-linolenic acid (ALA), some research is now starting to look at more novel fatty acids like stearidonic acid (SDA), and pinolenic acid (PLA), each presenting unique structures and potential benefits within various plant sources. One intriguing focal point is Ahiflower oil, a distinctive source that harbors both ALA and SDA. In this episode, Dr. Ella Baker of the University of Southampton discusses some of the science behind plant-derived fatty acids, offering a deeper understanding of their distinctive qualities, conversion pathways, and the captivating interplay between omega-3 and omega-6 fatty acids. Dr. Baker's research to date focuses on the metabolism, functionality, and underlying mechanisms of action of plant-derived fatty acids. Her interests include novel plant-derived fatty acids and exploring the effects on membrane structure and function.

Links: Go to episode page Subscribe to Premium Sigma's recommended resources Join our email newsletter for free About This Episode: Kidney stones, crystalline deposits formed within the kidneys, present a formidable challenge to individuals grappling with their debilitating effects. These mineral accumulations, though small in size, can inflict significant pain and discomfort as they navigate through the urinary tract. Understanding the nuances of dietary management and treatment for kidney stones is crucial for those seeking relief and prevention. What makes this subject particularly intricate is the diversity of kidney stones – a mosaic of compositions ranging from calcium oxalate to uric acid. Recognizing that not all kidney stones are created equal, dietitians and renal specialists tailor their recommendations to address the specific nature of the stones, unveiling a spectrum of dietary strategies that aim to alleviate symptoms and impede the recurrence of these insidious formations. In this episode, specialist renal dietitian Deepa Kariyawasam brings us through the main causes of kidney stones, the potential dietary interventions, and how to guide individuals toward personalized pathways for kidney stone management.

Acronyms: RDA = Recommended Dietary Allowance AI = Adequate Intake UL = Tolerable Upper Intake Level EAR = Estimated Average Requirement About This Episode: Dietary Reference Intakes (DRIs) are a set of nutrient reference values, developed in the US, that are used to assess and plan the nutrient intake of healthy individuals. They provide guidelines for the recommended amounts of various nutrients to maintain health and prevent deficiencies or excesses. Different countries may have their own sets of dietary reference values or guidelines that serve similar purposes but may be named differently. DRIs include several different reference values: Recommended Dietary Allowance (RDA) Adequate Intake (AI) Tolerable Upper Intake Level (UL) Estimated Average Requirement (EAR) DRIs play a crucial role in nutrition and public health for several reasons. DRIs provide specific recommendations for the intake of essential nutrients, helping individuals and health professionals understand the amounts needed to maintain good health. By establishing RDAs and ULs, DRIs help prevent nutrient deficiencies and toxicity, ensuring that individuals consume an appropriate range of nutrients. Governments and health organizations use DRIs to develop public health policies, nutrition programs, and guidelines for food fortification to improve the overall health of populations. For nutrition professionals, understanding DRIs is essential as it forms the basis for assessing and planning dietary recommendations for individuals and populations. Note: This episode is one of our Premium-exclusive episodes. To listen to the full episode, you'll need to be a Premium subscriber and access the episode on the private Premium feed. Otherwise, you can hear a preview of the episode above or on the public feed of the podcast. Links: Go to episode page Subscribe to Sigma Nutrition Premium

Links: Go to episode page (with episode resources) Subscribe to PREMIUM Get the Sigma email newsletter See Sigma's recommended resources About This Episode: Alzheimer's disease has a profound impact on individuals, families, and societies worldwide. As a progressive neurodegenerative disease, it not only robs individuals of their cognitive abilities but also places an immense emotional and economic burden on caregivers. Mechanistically, the causes of Alzheimer's are incredibly complex and not fully understood. And in terms of treatment, the landscape appears challenging. Drug discovery efforts for dementias, including Alzheimer's, have faced setbacks, leaving a void in effective treatments. Consequently, attention has shifted toward preventive strategies, including dietary patterns. From a prevention standpoint, both genetics and lifestyle should be considered. Which throws up many interesting questions… To what extent do genetic factors contribute to Alzheimer's risk compared to lifestyle choices, and how does this interaction influence disease development? What role does lifestyle play in Alzheimer's risk, and is there evidence supporting the influence of specific nutrients on cognitive health? How do diet patterns impact Alzheimer's risk? Are there discernible risk differences associated with specific dietary choices, and how do these interact with genetic factors, such as the ApoE genotype? In this episode, Drs. Ayesha Sherzai and Dean Sherzai are on the podcast to answer these questions and discuss this topic in more depth. About The Guests: Dr. Ayesha Sherzai is a neurologist and co-director of the Alzheimer's Prevention Program at Loma Linda University, where she leads the Lifestyle Program for the Prevention of Neurological Diseases. She completed a dual training in Preventative Medicine and Neurology at Loma Linda University, and a fellowship in Vascular Neurology and Epidemiology at Columbia University. She is also a trained plant-based culinary artist. Dr. Dean Sherzai is co-director of the Alzheimer's Prevention Program at Loma Linda University. Dean trained in Neurology at Georgetown University School of Medicine, and completed fellowships in neurodegenerative diseases and dementia at the National Institutes of Health and UC San Diego. He also holds a PhD in Healthcare Leadership with a focus on community health from Andrews University.

Links: Go to episode page (with episode resources) Subscribe to Premium Receive the Sigma Nutrition newsletter About This Episode: Numerous nutrition studies present findings of "no effect," but interpreting such results requires caution. A null finding, indicating an absence of impact from a nutrient or exposure, may not necessarily suggest a lack of effect overall. Instead, it could stem from issues related to the study's design, the nature of the exposure, or participant characteristics. We've often referred to such studies as being "null by design". These studies, often termed "null by design," may yield inconclusive results due to insufficient contrast in exposure levels to reveal a significant effect size. Additionally, participants' baseline nutrient status or intake can contribute to false negatives. For instance, if a study provides a nutrient to individuals already replete in that nutrient, it may lead to an erroneous conclusion. This phenomenon can be understood by considering the bell curve of activity for a nutrient. Moreover, a lack of methodological rigor can generate 'false negatives.' If previous literature indicates associations between high intake of a specific food or nutrient and certain outcomes, a study comparing levels of intake well below that threshold may produce a misleading result. Some challenges arise from an overly reductionist perspective. In disease processes, reductionism simplifies diseases to a single primary source at the cellular and molecular level. This perspective assumes that if a nutrient shows a relationship with health or disease outcomes at a population level, its biological activity should manifest in isolation. However, applying such assumptions to exposures like diet may not be tenable. In this discussion, we delve into the concept of "null by design" and present three specific studies with null findings, emphasizing the need for careful interpretation.

Links: Go to episode page (with supporting links/resources) Subscribe to PREMIUM Learn more about Sigma Nutrition Crushing Comparisons course About This Episode: Social comparison theory, developed by psychologist Leon Festinger in the 1950s, posits that individuals determine their own social and personal worth based on how they stack up against others. This theory suggests that people engage in social comparisons to evaluate their abilities, opinions, and attributes, often choosing relevant others for comparison. In the realm of body image and self-perception, social comparison theory becomes particularly pertinent, as individuals tend to assess their own bodies in relation to societal ideals and the bodies of others. This process of comparison can have profound implications for body dissatisfaction and the development of disordered eating patterns. This raises thought-provoking questions about the impact of social comparison theory on body image and eating behaviors. In this episode, Shannon Beer explores these questions and offers valuable insights into the complex interplay between societal influences, individual perceptions, and the development of body dissatisfaction and disordered eating. About The Guest: Shannon Beer is a registered nutritionist, health and confidence coach and certified Compassionate Mind Training facilitator. Shannon works with people aiming to improve their health through facilitating lasting behaviour change in their approach to diet, exercise and body image. She has developed a coaching framework that applies motivational interviewing, cognitive behavioral coaching, and acceptance and commitment therapy-aligned processes in a client-centered alliance toward their own values-based goals.

Questions Answered in This Epsiode: [02:16] How would you implement a calorie surplus for "bulking" in healthy trainees without compromising their health markers? [15:25] If you were to advise someone with a heavy workload and busy schedule on how to establish the 80/20 of a healthy lifestyle, what would you tell them? [24:36] Is coconut oil good or bad? What about claims that it cures cancer, Alzheimer's, etc.? [33:25] In the circumstance in which an individual has a normal ApoB yet an elevated LDL particle number, which value is more representative of risk? [41:39] Should you supplement in order to reach 100% of RDA for micronutrients? [46:35] Are raw oats a good ingredient to add to smoothies? Do they need to be cooked? [51:58] Is there any research supporting whether or not diet really impacts oral thrush? [55:21] Is there any benefit to supplemental collagen? Note: This is a Premium-exclusive "ask me anything" episode. You can access the full episode as a Premium subscriber. Join here.

Links: Go to episode page Subscribe to Premium Sigma's recommended resources Bite Me Nutrition – Australia Instagram: @jonosteedman @dannylennon_sigma About This Episode: There is no shortage of misleading, confusing and even dangerous nutrition information on the internet. And, unfortunately, much of it can sound very convincing and appealing to people who wish to improve their health. The result can be that they may end up ironically doing the opposite. At an individual level, dietitians and medical practitioners end up having to work with patients who have heard incorrect information or who have been following poor advice. What issues does this present? What is the most productive way to help patients and clients in this situation? How can we help give better information while also listening and caring for the patient? To discuss such questions, dietitian Jonathan Steedman is on the podcast to share his experiences and approaches to spreading evidence-based information in a palatable and productive manner. About The Guest: Jonathan Steedman is an Acredited Practising Dietitian (APD) in Australia. He currently works with patientes via telehealth services. He is well-known on social media for explaining confusing nutrition topics in a way that is understandable and engaging for the general population.

Links: Go to episode page (with study links) Subscribe to Premium Sigma's recommended resources Get our weekly email newsletter About This Episode: Insufficient energy availability can significantly disrupt normal hormonal, metabolic, and physiological processes, prompting the body to initiate a coordinated response aimed at conserving energy. While commonly viewed as beneficial for weight loss and managing cardiometabolic conditions in the current obesity epidemic, chronic energy deficiency in the context of modern sports and exercise nutrition is linked to adverse health outcomes and diminished athletic performance. Nevertheless, the evidence regarding the negative impact of energy deficit on physical capacity and sports performance is not entirely clear. Although severe energy deficiency can impair physical capacity, it's noteworthy that humans can enhance aerobic fitness and strength even in the presence of significant energy deficits. Strikingly, many elite athletes compete at the highest levels despite displaying evident signs of energy deficiency. This raises intriguing questions about how the human body adapts to energy deficits, challenging conventional views on the relationship between energy availability and athletic prowess. To discuss some potential reasons for this ability to maintain peak physical performance while suppressing energetically demanding physiological traits, researcher Dr. Jose Areta of LJMU is on the podcast to discuss his work in this area. About The Guest: Dr. José Areta currently works as a lecturer in Sports Nutrition and Metabolism at the School of Sport and Exercise Sciences at LJMU. José's primary interest is in the area of training-nutrient interactions in humans. In other words, he investigates how to manipulate ingestion of carbohydrates, fat and protein around training to optimise physical performance and health. The outputs of his research have not only expanded the knowledge of the field but had significant impact and influence on determining current dietary recommendations and practices world-wide. His work has provided novel insights in relation to the amount, timing, quantity and distribution of carbohydrates, fat and protein and dietary supplements around training. Over the last few years José has been developing his research in the area of the endocrinological, metabolic and physiological effects of energy restriction, in which he is currently growing his research team and capability.

Links: Episode page (with study links) Subscribe to Premium Join Sigma email newsletter About This Episode: The Portfolio diet is a nutritional approach that has garnered attention for its ability to reduce blood lipids and thus improve cardiovascular health. While past intervention trials have demonstrated significant reductions in blood lipids, a critical aspect often overlooked is the long-term impact, both in terms of adherence and disease outcomes. A recent study aimed to address this by looking at disease risk across three cohorts: the Nurses' Health Study I, Nurses' Health Study II, and the Health Professionals Follow-up Study. The study made use of a Portfolio Diet Score (PDS), a comprehensive metric that evaluates the diet's efficacy based on specific components. These components include positive rankings for plant proteins (especially from legumes), nuts and seeds, viscous fiber sources, phytosterols (mg/day), and plant monounsaturated fat sources. Conversely, the PDS negatively ranks foods high in saturated fat and cholesterol. In this episode, Dr. Andrea Glenn, the lead author of this study, discusses the intricacies of the research, providing insights into its findings and shedding light on how these findings resonate within the broader landscape of literature.

This episode is one of our Premium-exclusive AMA (ask me anything) episodes, where we answer questions submitted by Premium subscribers. To listen to the full 90 minute episode, you'll need to be a Premium subscriber and access the episode on the private Premium feed. Otherwise, you can hear a preview of the episode here. Full List of Questions: [01:50] How should one interpret the systematic reviews done by Hooper et al that report no association between modification or reduction of saturated fat intake with cardiovascular mortality, total mortality, non-fatal MI? [22.10] Given most people don't meet them, are public health targets for fruit and vegetables too high? [29.10] What is the role of homocysteine in heart disese? Is it causal? [40:45] Monounsaturated Fat: Good, Bad or Indifferent? [50:13] Is there evidence to suggest an upper limit for BMI, where even individuals with a 'healthy' body composition would be at elevated risk? [59:32] Where does the current research stand on the impact of diet on brain health? [01:08:48] Based on recent findings, do we have to throw out previous research on diet's impact on the gut microbiome?

Links: Go to episode page (with links to studies) Subscribe to PREMIUM Join Sigma's email newsletter Sigma's Recommended Resources About This Episode: Navigating the intricate landscape of sports nutrition is one that constantly evolves and challenges our understanding of optimal athletic performance. The delicate balance between advancing research and ensuring practical applicability in the high-speed realm of sports nutrition is a perpetual struggle. Decision-making is difficult, especially when faced with a scarcity of evidence. It's a challenge that resonates with many professionals in the field, prompting reflections on the art of making informed choices in the absence of conclusive data. In this episode, Dr. Andy Kasper, PhD shares his experiences and research in the field of elite sports nutrition. Dr. Kasper, a PhD in Nutrition and Physiology from Liverpool John Moores University, currently spearheads the Performance Nutrition department at Newcastle United Football Club. His illustrious career spans across elite football, rugby union, and rugby league, with notable stints at clubs like Chelsea, Fulham, Derby, England Rugby Union, Sale Sharks, London Irish, and Wasps, to name a few. A prolific contributor to academic publications, Dr. Kasper's insights have not only shaped the scientific landscape but have also directly influenced the nutritional strategies employed by top-tier athletes. Our conversation will traverse a myriad of topics, from the transformative changes witnessed in sports nutrition to invaluable advice for practitioners navigating this intricate terrain. We'll also delve into the delicate balance between advancing research and ensuring practical applicability in the fast-paced world of sports nutrition. Dr. Kasper will shed light on the Paper-to-Podium Matrix, a concept that bridges the gap between scientific discoveries and their real-world implementation in the pursuit of athletic excellence.

Links: Go to episode page (with study links) Subscribe to PREMIUM Receive our email newsletter About This Episode: The Oslo Diet-Heart Study was one of the earliest randomized controlled trials to explore the relationship between diet and heart disease. It aimed to investigate the impact of dietary interventions, specifically the reduction of saturated fat intake and an increase in polyunsaturated fat intake, on cardiovascular health. The Oslo Diet-Heart Study involved 412 men who had already suffered a myocardial infarction 1-2 years before the start of the intervention. Despite some known limitations, the Oslo Diet-Heart Study played a role in shaping early understanding on the relationship between dietary fat, cholesterol levels, and heart disease. Subsequent research and larger studies have contributed to a more nuanced understanding of the complex factors influencing cardiovascular health. In this episode we discuss why this trial is important in the history of diet-heart research and how it connects to other seminal work in the field.

Links: Go to episode page (with study links) Receive Sigma's email newsletter Subscribe to PREMIUM - get study notes to this episode About This Episode: In 1959 a landmark clinical trial, often referred to as the LA Veterans Study, began with the aim to investigate the effects of replacing dietary saturated fats with polyunsaturated fats, on the progression of atherosclerosis and cardiovascular outcomes. This was an eight-year clinical trial in 846 domiciled male veterans in the US. The diets between the control and experimental groups differed by saturated fat and polyunsaturated fat (particularly linoleic acid) content, but were similar in calories and total dietary fat. The findings of the study suggested that replacing saturated fat with polyunsaturated fat was beneficial for reducing heart disease risk. However, the study also reported an unexpected increase in non-cardiac mortality in the intervention group, which raised concerns. In this episode, we discuss why the LA Veterans Study was such a seminal trial and what we can learn from it.

Links: Go to episode page (with resources) Subscribe to Premium Learn more about Sigma Nutrition About This Episode: The Lyon Diet Heart Study (LDHS) is often cited as one of the pivotal studies that helped establish the Mediterranean diet as a recognized and recommended dietary pattern for cardiovascular health. A clinical trial conducted in Lyon, France, the LDHS showed significant reduction in cardiac death could be achieved in secondary prevention patients using a dietary intervention. Conducted between 1992 to 1996, the study involved 605 participants who had previously experienced a heart attack (myocardial infarction). LDHS showed an incredible 75% lower risk of cardiac death in these patients. This remarkable reduction was unexpected and led to considerable attention from the medical and scientific communities. LDHS is interesting to dig into for several reasons. First, it's clever methodology was able to account for some challenges of doing nutrition research. Second, the dietary intervention, whilst named as a "Mediterranean diet", should perhaps be considered differently. In this episode, Alan and Danny dig into all the details, highlighting some important lessons we can take from LDHS.

Links: Go to episode page (with study links) Subscribe to Premium Past episodes referenced: Episodes 493, 481 & 317 Further reading: How Diet Influences Heart Disease Risk About This Episode: The Sydney Diet-Heart Study was a clinical trial conducted in the 1960s and 1970s that aimed to examine the hypothesis that reducing saturated fat intake in the diet would lead to a reduced risk of heart disease. However, it really only gained attention after a more recent re-analysis by Ramsden et al., which in recent years has been used as supporting evidence for the idea that increased polyunsaturated fat (PUFA), and specifically linoleic acid, in addition to reduced saturated fat intake, can increase heart disease risk. This was based on the findings that substituting linoleic acid in place of saturated fat increased all-cause, CVD and CHD mortality. This is of course counter to prevailing consensus and guidelines in this area, which routinely show reduced risk on replacing SFA with PUFA. Could this trial undermine the common conclusions that replacing saturated fat with polyunsaturated fat decreases heart disease risk? In this episode Alan and Danny discuss some of the crucial aspects to understand about this study and what it means for what conclusions can be made about the impact of PUFA broadly, and linoleic acid specifically, on our health.

Note: This is a Premium-exclusive episode, so in order to listen to the full episode you'll need to subscribe to Sigma Nutrition Premium. About This Episode Nutritional epidemiology has faced strong criticism over time. While some of the methodological limitations are fair, often there are criticisms that are misguided and inaccurate. In this episode, Danny touches on a few examples of the misunderstandings of the field and how such claims can be addressed in a more accurate manner. Links: Subscribe to Premium Go to episode page See recommended resources Receive weekly emails from Sigma

Links: Go to episode page (with study links) Subscribe to PREMIUM Receive emails from Sigma Nutrition Sigma's Recommended Resources About This Episode: The field of research exploring sex differences in exercise response has yielded intriguing findings, shedding light on the complex interplay between biology, physiology, and training adaptations. One of the fundamental areas of investigation pertains to sex disparities in strength, power, and hypertrophy. Historically, it's been well-established that males, on average, exhibit greater absolute strength and muscle mass compared to females. This discrepancy often traces its roots back to inherent physiological distinctions. However, when it comes to responses to strength and hypertrophy training, the narrative becomes more nuanced. Research indicates that, when individuals of both sexes follow matched resistance training protocols, the relative improvements in strength and hypertrophy are quite similar. So, do women need to be trained differently than men? The answer, it appears, is not as much as one might assume. The principles of progressive overload, specificity, and other training fundamentals remain constant. While individualization is key, the idea of drastically distinct training guidelines based on sex lacks compelling empirical support. The guest in this episode, Dr. David Nolan, is a researcher in the area of sex differences in exercise response, and has looked at the influences of menstrual cycle and hormonal contraceptive use in female athletes on their performance. In this episode, we discuss the research to date, and what this means practically for athletes and coaches.

Links: Subscribe to PREMIUM to get study notes to this episode Go to episode page to see background detail & links See our recommended resources for further learning Previous episodes referenced: SNP17: Is Personalized Nutrition Superior to General Nutrition Advice? 414: Will Machine Learning Overtake Traditional Nutrition Research Methods? 469: Chrononutrition – New Findings & Updated Views About This Episode: To mark the 500th episode of the podcast, Danny and Alan take a look at some of the current outstanding questions in nutrition science, what areas have largely been resolved, and how their own thinking has evolved and changed over time. This brings them into areas such as personalized nutrition, ultra-processed foods, time-restricted eating, salt & health, and the difference between being "evidence-based" and "reference-based". We Discuss: Outstanding questions in nutrition science Personalized nutrition Ultra-prosessed foods (UPFs) Diet-Microbiome-Health Omega-3 Fatty Acids Largely resolved questions Sodium & CVD risk TRE/TRF Macronutrient breakdown & weight loss Evolution in our thinking Epistemology at the forefront "Reference-based" to evidence-based Reading research: understanding "highest quality evidence"

Links: Subscribe to PREMIUM Go to episode page (with further reading links) Receive our weekly emails About This Episode: Sensory cues, comprising taste, smell, texture, and appearance, serve as the initial drivers that influence our food preferences and liking for particular items. These sensory cues can be both inherent, such as the natural sweetness of fruit, and learned, as in the association between a particular aroma and a favorite dish. One crucial aspect of this research is delving into how sensory properties of food, like texture and taste, contribute to our choices and consumption patterns. Food texture, for example, plays a key role in determining how quickly we consume a meal, with softer textures often being associated with faster eating rates. Sensory intensity and palatability are also central themes in this research. Moreover, research into dietary fat reveals intriguing phenomena like "fat blindness," where the ability to discriminate different levels of fat diminishes as taste intensity increases. Understanding these relationships can help shed light on factors contributing to overeating and potential avenues for behavior modification. To give us a better insight into this field of research, Professor in Sensory Science and Eating Behavior at Wageningen University, Prof. Ciarán Forde, is on the podcast to discuss these ideas.

Links: Subscribe to PREMIUM Go to episode page Learn more about the podcast Sigma's recommended resources About This Episode: PREDIMED (Prevención con Dieta Mediterránea) is a landmark clinical trial conducted in Spain. The study made a huge splash due to the rarity in nutrition of having large RCTs with hard endpoints. In addition, it had results of a large magnitude; showing a 30% reduction in cardiovascular events. But the study did face criticisms and controversies over methodological issues, including randomization procedures at certain centers, ultimately leading to a retraction of the original paper and a re-analysis. Participants in the PREDIMED trial were randomly assigned to one of three groups: A Mediterranean diet supplemented with extra-virgin olive oil. A Mediterranean diet supplemented with mixed nuts (walnuts, almonds, and hazelnuts). A control group following a low-fat diet. Despite the issues it still ends up being an incredibly useful source of data. In this episode we discuss the findings from PREDIMED, some of the potential limitations, and where it sits among the wider Mediterranean Diet literature. Note: This is a Premium-exclusive episode, so in order to listen to the full episode you'll need to subscribe to Sigma Nutrition Premium.

Links: Subscribe to PREMIUM Go to episode page (with linked studies) Receive the weekly Sigma email newsletter Recommended resources About this Episode: The PROPEL (Promoting Successful Weight Loss in Primary Care in Louisiana) trial was a cluster-randomized weight loss trial, specifically tailored to address the pressing health concerns of an underserved population in Louisiana, where obesity rates have reached alarming levels. The core of the intervention comprises a pragmatic, high-intensity lifestyle-based obesity treatment program, thoughtfully designed to be integrated within primary care settings. Over a 24-month duration, this multi-component weight loss program is delivered by skilled health coaches who are embedded in primary care clinics, with the aim of instigating substantial and sustainable weight loss outcomes. In this study, 803 participants were enrolled, of whom 67% identified as Black and 84% as female, thereby ensuring a diverse representation. The research design randomized 18 clinics, allocating them equally into two groups: usual care and an Intensive Lifestyle Intervention (ILI). The usual care group continued to receive their customary primary care, serving as the benchmark against which the ILI's efficacy will be measured. In this episode we have the opportunity to delve deeper into the intricacies of the PROPEL trial and gain insights from one of its lead researchers, Dr. John Apolzan of the Pennington Biomedical Research Center.

Links: Go to episode page Subscribe to PREMIUM Recommended resources Receive Sigma's free email newsletter Learn more about the podcast About This Episode: Food frequency questionnaires (FFQs) have been widely employed in nutrition research to assess dietary intake patterns among study participants. However, debates surrounding the reliability of FFQs have persisted both inside and outside the academic community. These debates primarily revolve around issues related to measurement error, recall bias, and the appropriateness of FFQs for diverse populations. One prominent concern is the potential for measurement error in FFQs. These questionnaires rely on self-reported data from participants, which can introduce inaccuracies due to memory limitations and social desirability bias. Participants may not accurately recall their food consumption frequencies and portion sizes, leading to imprecise estimates of nutrient intake. Recall bias is another critical issue in the reliability debate. Participants may selectively remember or misreport the consumption of certain foods or nutrients, leading to an overestimation or underestimation of actual dietary intake. Two concepts are crucial to understand: validity and reproducibility. FFQs are validated by cross-referencing the FFQ data with other dietary assessment tools (or other methods). It's also important to consider if an FFQ gives reproducible results when used on multiple occasions. When we ask "are FFQs reliable?", we must first understand the conceptual exposure of interest: average intake over time. Second, we must consider what nutrients we are looking at. And third, in what population. In this episode, Danny & Alan discuss the reliability of FFQs and how to have a deeper, more accurate understanding of their use. They take a look at valid critcisms of FFQs, as well as some of the more ill-informed criticisms.

Links: Subscribe to Premium Sigma recommended resources Learn more about the podcast About this episode: In 1985 a paper titled "Sick Individuals and Sick Populations" was published in the International Journal of Epidemiology. The paper, authored by eminent epidemiologist Geoffrey Rose, can be considered as seminal and important because it brilliantly raised the concept of the "prevention paradox" and challenged traditional approaches to public health and preventive medicine. The paper's insights have had a lasting impact on how we understand and approach population health interventions. And it raised many contentious public health issues, which are still debated and relevant today. The ideas have very important implications for how we can tackle diet-related diseases in meaningful ways. In this episode, Danny and Alan discuss the central themes of the paper, why they are so crucial to understand, and what this means for our understanding of diet and chronic disease prevention.

Links: Go to episode page Subscribe to PREMIUM Get our free weekly emails Learn more about Sigma Nutrition Radio About This Episode: The Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (ATBC) stands as a seminal and pioneering research endeavor within the domain of epidemiology and cancer prevention. Conducted in Finland, the study aimed to examine the potential protective effects of alpha-tocopherol (vitamin E) and beta-carotene supplementation against the occurrence of various cancer types, particularly lung cancer, among male smokers. Initiated in the early 1980s, the study's comprehensive design, rigorous methodology, and its focus on a specific high-risk population have contributed significantly to the understanding of the interplay between dietary antioxidants and cancer risk. The ATBC study was founded on a growing body of evidence suggesting the potential role of antioxidants in mitigating the deleterious effects of oxidative stress and free radical damage, which are recognized as contributors to carcinogenesis. The selection of male smokers as the study cohort was strategically significant, given the heightened susceptibility of this group to lung cancer and other malignancies due to the synergistic action of smoking and oxidative stress. The study's rigorous double-blind, placebo-controlled design ensured a high degree of scientific rigor, minimizing biases and confounding factors that might influence the outcomes. One of the primary reasons for the study's seminal status is its contribution to the understanding of the complex relationship between antioxidants and cancer risk. While the study did not find a significant reduction in lung cancer incidence among the intervention group receiving alpha-tocopherol and beta-carotene supplements, its findings spurred critical discussions within the scientific community. The neutral or inconclusive results underscored the intricate nature of carcinogenesis and highlighted the limitations of simplistic cause-and-effect interpretations in the context of cancer prevention. Moreover, the ATBC study contributed to a shift in research paradigms, prompting scientists to explore broader dietary and lifestyle factors that influence cancer risk beyond single-nutrient interventions. In this episode we discuss the three most important publications from the study, with a specific look at what crucial lessons they teach us about the nuances, challenges, and unique aspects of nutrition as a scientific field.

Links: Episode page with extra resources Subscribe to PREMIUM Receive our free weekly emails Learn more about Sigma Nutrition Radio About this Episode: The field of circadian biology has long been associated with regulating diurnal physiological processes, notably the sleep-wake cycle. However, recent advances have unveiled a broader role for circadian clocks across various tissues, including skeletal muscle. Within this context, the investigation of circadian clocks within the skeletal muscle milieu has emerged as a frontier of scientific inquiry. These intrinsic timekeeping mechanisms exhibit multifaceted regulatory capacities beyond mere temporal synchronization. This episode delves into the implications of "circadian clocks" operating within skeletal muscle tissue, with the esteemed Prof. Karyn Esser as this week's guest. Her pioneering work has been instrumental in understanding the interplay between circadian rhythmicity and muscular physiology.

Links: Go to episode page (with study links & resources) Subscribe to PREMIUM Receive our weekly newsletter More episodes on cholesterol & heart disease About This Episode: The Multiple Risk Factor Intervention Trial (MRFIT) was a groundbreaking clinical trial conducted in the 1970s and 1980s. Its main objective was to investigate the relationship between various risk factors and the incidence of heart disease. The study aimed to determine whether modifying risk factors, such as high blood pressure, high cholesterol levels, and smoking, could lead to a reduction in cardiovascular events. The trial spanned several years, with participants being followed up for a period of approximately six years to assess the incidence of cardiovascular events and mortality. The primary outcome measures included coronary heart disease (CHD) mortality and overall mortality. The MRFIT trial yielded several important findings that have significantly influenced our understanding of cardiovascular health and prevention strategies. In this episode we take a look at why this is such seminal research, as well as the contribution of one of the greatest researchers ever in the field, Jeramiah Stamler.

Links: Go to episode page (with resources for this episode) Subscribe to PREMIUM Join the Sigma email newsletter Learn more about Sigma Nutrition Radio About this Episode: One of the most important and influential papers in nutrition science is one by Ancel Keys and his colleagues that was published in The Lancet in 1957. This seminal paper examined the relationship between dietary fat intake and serum cholesterol levels. The researchers investigated how different types of fats in the diet affected cholesterol levels in a series of their previous tightly-controlled dietary experiments.. Those studies involved feeding the participants various diets with different compositions of fats. The researchers analyzed the participants' blood samples to measure changes in serum cholesterol levels in response to dietary changes. The most important aspect of this paper is the presentation of the 'Keys Equation'; a predictive equation for the impacts of saturated, monounsaturated, and polyunsaturated fats, and dietary cholesterol, on blood cholesterol levels. Crucially, the Keys Equation identifies the importance of the ratio of polyunsaturated to saturated fats in the diet; known as the 'P:S ratio'. It showed that the P:S ratio is the most important dietary factor impacting blood cholesterol levels. And specifically that saturated fats increase total and LDL cholesterol twice as much as polyunsaturated fats lower them. The findings of this study were significant in highlighting the potential impact of dietary fat subtypes on serum cholesterol levels and heart disease risk. It contributed to the growing body of evidence supporting the hypothesis that high serum cholesterol levels, particularly due to a diet rich in saturated fats, were associated with an increased risk of cardiovascular diseases. In this episode, as part of our new series taking an in-depth look at seminal nutrition studies, we go through this influential paper from Keys, Anderson and Grande.

This is a Premium-exclusive episode, so here you'll only hear a preview. In order to listen to the full episode you'll need to subscribe to Sigma Nutrition Premium. About This Episode: It has been clearly demonstrated that elevated LDL-cholesterol (LDL-C), or perhaps more specifically pro-atherogenic lipoproteins, is causal in atherosclerosis development in humans. One crucial concept within this is that the risk relates not only to the magnitude of elevated LDL-C, but the duration of exposure. Thus, the role of LDL-C in driving atherosclerosis is referred to as a "cumulative, integrated exposure over the lifecourse". But, what exactly does this mean? In this episode, Danny discusses the cumulative exposure model of LDL-C in atherosclerosis, the evidence supporting it, and the implications of this for the "debates" that get raised in relation to LDL-C (or apoB-containing lipoproteins) and heart disease. Links: Subscribe to PREMIUM See more episodes on heart disease and lipids Receive the free Sigma email newsletter

Links: Resources and info for this episode Subscribe to PREMIUM Receive Danny's weekly email newsletter About This Episode: Losing at least 5% of one's initial body weight is associated with improvements in glycaemic control, blood pressure, triglyceride levels, and other positive outcomes. Due to these reasons, it is typically recommended that individuals classified as overweight or obese should engage in effective weight loss interventions. However, despite the potential for clinically significant weight loss through these interventions, weight regain is a common occurrence. This can be attributed to a combination of low adherence to weight control strategies and compensatory physiological mechanisms that influence weight regain. Consequently, this may result in a cycle of losing and regaining weight over the long term, which is commonly referred to as "weight cycling." There are concerns regarding the potential harm to health and increased risk of chronic diseases associated with weight cycling. Some mechanisms have been proposed, such as the loss of lean mass during weight loss periods that is not regained when weight is regained. However, the evidence supporting the harmful effects of weight cycling on health is incomplete and many unanswered questions remain. In this episode, we will examine the evidence published to date and draw evidence-based conclusions regarding the impact of weight cycling on long-term health.

Links: Episode Resources Subscribe to PREMIUM Receive our weekly newsletter About This Episode: There has been interest in, and debate about, how protein intake impacts metabolic health, particularly in relation to insulin resistance and type 2 diabetes risk. Recently, there has been interest in higher protein intakes as an intervention in diabetes, owing to a variety of potential mechanisms. For example, the satiety value of protein, the promotion of insulin secretion by protein, and imapcts on incretin hormones. However, others have warned against high protein intakes. With some going as far as to claim high, or even moderate, protein intakes can lead to insulin resistance or negatively effect beta-cell function. In this episode, we look at the research typically cited in support of such claims, and dig into the details. We consider the overall evidence in this area to answer the question 'do high protein diets cause insulin resistance or increase diabetes risk?'.

Links: Go to episode page Subscribe to PREMIUM Receive our free weekly emails About This Episode: The management of type 2 diabetes has long been a challenge, but a new study conducted by researcher Mark Lyngbaek and his colleagues has the potential to add important considerations to the approach to treatment. Titled the "DOSE-EX" randomized clinical trial, their study uncovers the impact of exercise and weight loss on beta-cell function, a key factor in diabetes progression. DOSE-EX is a four-armed randomized trial involving 82 individuals with newly diagnosed type 2 diabetes. The participants were divided into four groups: standard care, calorie restriction, calorie restriction with exercise three times per week, and calorie restriction with exercise six times per week. Over a span of 16 weeks, the researchers assessed the effects of these interventions on beta-cell function using various indicators. The study's findings are incredibly interesting, demonstrating that exercise in combination with diet-induced weight loss leads to a substantial improvement in glucose-stimulated beta-cell function. Importantly, the results indicate the importance of considering both: a) the exercise dose, and b) the methodology of assessing beta-cell function, when evaluating intervention effectiveness. In this episode, Dr. Lyngbaek will elucidate the implications of these findings for the management of type 2 diabetes. We will explore the potential of exercise as a therapeutic tool, its optimal dosage, and the considerations for integrating it into individualized treatment plans. About The Guest: Dr. Mark Lyngbæk is a physician, currently in an introduction position at the Department of Rheumatology and Internal Medicine 2 at Holbæk Hospital, and also a PhD student at the Centre for Physical Activity Research at Rigshospitalet. His research has looked at exercise, beta-cell function and type 2 diabetes. He is supported by a research grant from the Danish Diabetes Academy, which is funded by the Novo Nordisk Foundation (grant number NNF17SA0031406). The Centre for Physical Activity Research is supported by TrygFonden (grants ID 101390, ID 20045, and ID 125132). Subscribe to PREMIUM

Links: Subscribe to PREMIUM Episode page Receive Sigma emails About this Episode: We've just released a lengthy 'ask me anything' episode, where Dr. Alan Flanagan addressed specific listener questions, over on the Sigma Nutition Premium feed. In this episode, you'll hear one detailed answer from that AMA, in which Alan discusses the concept of "causal risk factors". This is a term that is regularly mentioned on the podcast, and has a very specific and important meaning. This episode will give you an in-depth understanding and comfort with the term, which will enhance your future understanding and learning. If you wish to hear the other 10 questions Alan answered, you can subscribe to Sigma Nutrition Premium here.

Links: Go to episode page (with resources) Receive Danny's weekly emails Twitter: @NutritionDanny Subscribe to PREMIUM About This Episode: In the UK, there is a threefold higher incidence of type 2 diabetes in UK African and Caribbean (AfC) communities, compared to the general population. And ethnic inequalities in type 2 diabetes treatment and outcomes have been documented. And so addressing these inequalities is an urgent healthcare priority in the UK. Differences in outcomes relate to physiological differences as well as pragmatic issues and structural barriers. Professor Louise Goff has done pioneering work in relation to both aspects. Prof. Goff's research has highlighted ethnic differences in type 2 diabetes pathophysiology between those in UK African and Caribbean groups and white Europeans. This means that typical screening for diabetes may not be as useful for AfC communities, in addition to treatments not being as appropriate. In addition, there are noted differences in engagement with diabetes education services and self-management advice. This may be due to the fact that the delivery of information is not culturally relevant to those in AfC communities. And so diabetes structured education programs have been found to be less successful in people from minority ethnic groups. Prof. Goff has attempted to address this by developing a culturally tailored self-management education and support program for type 2 diabetes in black-British adults. This program, called the Healthy Eating and Active Lifestyles for Diabetes (HEAL-D) program, has initially been trialed with local Black African and Caribbean communities and healthcare providers in South London. In this episode, Prof. Goff discusses the ethnic differences in diabetes pathophysiology and the other factors underlying the inequalities in diabetes outcomes in black African and Caribbean communities. Go to episode page (with resources)

Links: Episode page (with links to resources) Receive Danny's weekly emails Subscribe to PREMIUM About This Episode: The topic of whether hunger and satiety are affected by the time of day has generated considerable interest within the nutrition research community. Researchers have been particularly intrigued by the potential influence of circadian rhythms on caloric intake throughout the day. Initially, a number of studies proposed that consuming high energy intakes in the morning could lead to significantly greater weight loss compared to evening consumption. And while much attention was placed on the hypothesis that differences in expenditure were the cause, more recent research has called that into doubt. And so, it is crucial to consider the possibility that other factors may be contributing to the outcomes observed in the intervention trials. In recent years, a series of papers has suggested an alternative explanation; the impact of time-of-day energy intake on appetite and hunger. In this episode, Alan and Danny take a look at the current evidence related to this connection between time-of-day, appetite, and energy intake. And then, from that, what does this mean for how calorie distribution may affect dietary intake, body composition and health.

Links: Join notification list for book pre-orders Go to episode page (w/ resources) Subscribe to Sigma Nutrition Premium About This Episode: "Weight cutting" is a common practice in weight-class based sports. And typically, combat sport athletes have reported cutting the largest amounts of weight for competition. The concept of cutting weight is based on the assumption that a size advantage gives a performance advantage in combat sports. And by getting into a lower weight class than their "normal" weight, athletes can enjoy an advantage (or, more accurately, not be at a disadvantage). The decrease in weight from an athlete's habitual weight to their weight-class limit typically has two phases: a chronic weight loss phase (gradual dieting to lose fat mass), and an acute weight loss phase (rapid declines in weight due to losses of water, glycogen and gut residue). To discuss the science, practical application and dangers of weight cutting strategies, performance dietitian Jordan Sullivan is on the podcast. Jordan has been the performance dietitian for several years to Israel Adesanya, Alexander Volkanovski, Leon Edwards, Dan Hooker, Kai Kara-France, and many other well-known names. And he is the co-author, along with Danny, of the new textbook 'Making Weight: The Ultimate Science Based Guide to Cutting Weight for Combat Sports'.

Links: Go to episode page (with resources) Receive Danny's weekly emails Subscribe to PREMIUM Twitter: @NutritionDanny Instagram: @dannylennon_sigma About This Episode: Peaks in blood glucose (or "blood sugar spikes") are commonly highlighted as something harmful to health. And, of course, an excessively high blood glucose response to a meal can be problematic, or at least indicate there is a problem. However, elevations in blood glucose after eating are a normal physiological response. And "bad" blood glucose responses are those that stay high for a prolonged period; i.e. after elevating, they don't return to normal within an appropriate period of time. But now many normoglycemic people are worrying about normal blood glucose responses, due to information that portrays even moderate elevations in blood glucose as harfmul. To add to the confusion, people are looking at standardized cut-off thresholds for diabetes and pre-diabetes, and mistakenly using them to label their own response to eating as measured by a continuous glucose monitoring (CGM) device. When it comes to normoglycemic people, there is still a grey area in relation to how much of a glucose spike is a cause for concern. And given that there are still open questions that evidence has not fully answered yet, there is room for different interpretations of how to answer this question. So what actually is a blood glucose peak that is "too high"? Is it 7.8 mmol/L (140 mg/dL)? 10.0 mmol/L (180 mg/dL)? 11.1 mmol/L (200 mg/dL)? Or do we even need to think about this once standard measures (e.g. HbA1C) are normal? To discuss this interesting area, Dr. Mario Kratz and Dr. Nicola Guess are on the podcast to offer some perspectives and their conclusions from the current evidence base. Blood Glucose Unit Conversions: 1.7 mmol/L = 30 mg/dL 7.0 mmol/L = 126 mg/dL 7.8 mmol/L = 140 mg/dL 9.0 mmol/L = 162 mg/dL 10.0 mmol/L = 180 mg/dL 11.0 mmol/L = 198 mg/dL 11.1 mmol/L = 200 mg/dL

Links: Go to episode page Receive Danny's weekly emails Subscribe to PREMIUM About This Episode: Menopause is commonly associated with hormonal changes and physical symptoms, such as hot flashes, mood changes, sleep issues, and weight gain. Based on anecdotal reports, another interesting question emerges: what is the potential impact of menopause on appetite? As women undergo this transformative phase, many report fluctuations in their food intake and body weight, raising the question: Does menopause alter appetite? Understanding the relationship between menopause and appetite is of great significance, as it can potentially provide insights into the mechanisms behind weight gain and obesity risk that often accompany this stage of life. Furthermore, comprehending the factors that contribute to changes in appetite during menopause could aid in the development of tailored interventions and strategies to support women's overall health and well-being. In this episode, we delve into the research to see if we can unearth any answers. What studies have been done? What results do we see? What conclusions does this allow us to make? And what does future research need to do in order to provide better answers?