#518: Nutritional Geometry, Philosophy of Science & A Case for Reductionism – Prof. David Raubenheimer & Jonathan Sholl, PhD
Release Date: 04/09/2024
#589: Causal Inference in Nutrition Science – Daniel Ibsen, PhD
Sigma Nutrition Radio
This episode explores how asking better questions and using stronger methods can resolve much of the confusion in nutrition science. Dr. Daniel Ibsen discusses why nutrition research often produces conflicting results and how careful methodological thinking can clarify true diet-disease relationships. Nutrition science has unique challenges – diets are complex, people self-report their food intake imperfectly, and we can’t easily run long-term diet experiments on people. Dr. Ibsen explains how embracing concepts like food substitution analysis, the “target trial” framework, and...
info_outline
#588: Menstrual Cycle “Syncing”: Do the Claims Hold Up to Evidence? – Expert Panel
Sigma Nutrition Radio
How much do hormonal fluctuations really influence performance and recovery? Should women be adjusting their training and nutrition based on the menstrual cycle? And do female athletes need different protein strategies or recovery protocols than men? These are questions that have fuelled countless online claims, from rigid “cycle syncing” programmes to supposedly gender-specific nutrition rules. But how much of that is actually grounded in evidence? In this episode, the conversation tackles those debates head-on, exploring what we truly know about female physiology, adaptation, and...
info_outline
#587: How Should Nutrition Be Taught in Medical Training? – Akash Patel
Sigma Nutrition Radio
This episode centers on the critical gap in nutrition education within medical training and efforts to bridge it. Guest Akash Patel, a medical student who led a pilot nutrition curriculum, discusses why doctors receive little formal training in nutrition despite poor diet being a major driver of disease. With diet-related conditions (obesity, diabetes, cardiovascular disease, etc.) contributing heavily to morbidity and healthcare costs, the conversation highlights a pivotal push to better equip physicians in nutritional knowledge and counseling. Patel’s work comes at a turning point: there...
info_outline
#586: The Manufactured Collapse of Expertise
Sigma Nutrition Radio
Never before has there been greater access to information about nutrition and health. But never before has there been such a low barrier to being seen as an “expert”. There are large numbers of people getting information from, and basing their health decisions on, people who don’t have direct expertise in the field in which they are talking about. Moreover, some promote the lack of domain expertise as a feature, not a bug. They claim that those that were conventionally seen as domain experts are either brainwashed, lazy in their thinking, or outright corrupt. And the solution is instead...
info_outline
SNP46: Reviewing Six Key Insights from the Year’s Conversations
Sigma Nutrition Radio
This is a Premium-exclusive episode of the podcast. To listen to the full episode you need to be subscribed to . Each year, the conversations on Sigma Nutrition Radio aim to examine the ideas that shape how we understand nutrition, health, and human behavior. This episode brings together the key insights from those discussions, revisiting the most important themes, emerging evidence, and shifts in understanding from the past year. Across topics such as dietary guidelines, ultra-processed foods, sleep, metabolism, environmental exposures, and the psychology of eating, this review...
info_outline
#585: Why We Think Poorly: Reason, Emotion, and Evidence-Based Reasoning
Sigma Nutrition Radio
We take a look at critical thinking in science and healthcare, examining how we often fall prey to cognitive biases, emotional reasoning, and flawed thinking. Drawing from six different experts in their respective fields, the episode explores why we sometimes believe we are being rational when in fact our conclusions aren’t truly evidence-based. The discussion spans what genuine evidence-based practice means, how domain expertise matters, and how factors like identity, beliefs, and emotions can derail objective reasoning. Timestamps [02:56] Dr. David Nunan on evidence-based medicine...
info_outline
#584: EAT-Lancet: Does the Planetary Health Diet Improve Human Health?
Sigma Nutrition Radio
How should we think about diets that claim to optimise both human and planetary health? Can a single “reference diet” really balance the complex trade-offs between nutrition adequacy, chronic disease prevention, and environmental sustainability? These questions have gained renewed attention with the release of the 2025 update to the EAT-Lancet Planetary Health Diet. The original 2019 report proposed a mostly plant-based dietary pattern designed to improve population health while staying within planetary boundaries. But since then, new data have emerged—on nutrient requirements, disease...
info_outline
#583: Ultra-Processed Foods & Fixing the Food Environment – Kevin Hall, PhD
Sigma Nutrition Radio
Ultra-processed foods have become central to the way we eat and to many of the challenges we face in public health nutrition. They dominate supermarket shelves, shape population diets, and often appear as the prime suspect in rising obesity and metabolic disease rates. But beyond the label itself, what exactly makes these foods problematic? Is it their nutrient composition, their texture and palatability, the rate at which we consume them, or the broader environments that make them so accessible and appealing? The debate around ultra-processed foods sits at the intersection of metabolic...
info_outline
SNP45: Antioxidants – What You Need To Know
Sigma Nutrition Radio
This is a Premium-exclusive episode of the podcast. To listen to the full episode you need to be subscribed to . What exactly are “antioxidants,” and why do they get so much hype? We often hear that blueberries, dark chocolate, and red wine are healthy because they’re packed with antioxidants – but is the story really as simple as “more antioxidants = better health”? In this episode, Danny explores the true role of antioxidants in the body, challenging simplistic narratives. Are antioxidants magic molecules that single-handedly prevent aging and disease? Or is the...
info_outline
#582: GLP-1 Agonists: Side Effects, Management and Diet – Dr. Spencer Nadolsky
Sigma Nutrition Radio
GLP-1 receptor agonists have emerged as a groundbreaking tool in obesity treatment. In this episode, Dr. Spencer Nadolsky (an obesity specialist) explains how these medications are now yielding unprecedented weight loss outcomes in people with obesity. The discussion centers on GLP-1 agonist drugs like semaglutide and tirzepatide: how they work, how much weight loss they can produce, and why they represent a paradigm shift in obesity management. Importantly, the conversation addresses practical aspects of using these drugs, including managing their side effects and optimizing...
info_outlineLinks:
- 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.