#518: Nutritional Geometry, Philosophy of Science & A Case for Reductionism – Prof. David Raubenheimer & Jonathan Sholl, PhD

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