Podcast
Sigma Nutrition Radio
Hosted by Danny Lennon · EN
Discussions about the science of nutrition, dietetics and health. The podcast that educates through nuanced conversations, exploring evidence and cultivating critical thinking. Hosted by Danny Lennon.
638episodes
Episodes
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#566: Can We Maintain Weight Loss? Pharmacology and Behavior – Tara Schmidt, RD
Jun 10, 202500:51:13Tap to summarizeGLP-1 receptor agonists have changed the landscape of obesity treatment, offering levels of weight loss once thought unattainable without surgery. But what happens after the weight is lost? And can we really talk about success without talking about maintenance? While much of the public discourse fixates on dramatic weight loss numbers, the harder question is what comes next. Can lifestyle interventions alone sustain weight loss after GLP-1 cessation? How do metabolic adaptations and behavioral relapse factor in? And what does the data actually show about relapse rates, nutritional adequacy, and lean mass preservation when using these medications? In this episode, Danny sits down with Tara Schmidt, dietitian at the Mayo Clinic, to examine the intersection of pharmacology and behavior in long-term weight management. Tara Schmidt is a registered dietitian and an instructor of nutrition at Mayo Clinic. As the lead dietitian for the Mayo Clinic Diet, she provides guidance rooted in evidence-based principles. She hosts the Mayo Clinic On Nutrition podcast and co-authored The Mayo Clinic Diet: Weight Loss Medications Edition. Timestamps [05:17] Understanding weight loss maintenance [08:44] Defining success in weight loss maintenance [11:54] Predictors of maintenance: self-monitoring and behavioral strategies [23:37] Pharmacological interventions: GLP-1 receptor agonists [31:06] Dietary considerations for those taking GLP-1 RAs [37:07] Addressing misconceptions about weight loss drugs [42:48] Final thoughts and takeaways [48:49] Key ideas (Premium-only) Links/Resources Subscribe to Sigma Nutrition Premium Go to episode page Join the Sigma email newsletter for free Enroll in the next cohort of our Applied Nutrition Literacy course Visit sigmanutrition.com
Transcribe →#565: How Zinc Insufficiency Impacts Inflammation, Immunity & Aging – Prof. Emily Ho
Jun 3, 202500:44:28Tap to summarizeZinc is an essential micronutrient that often flies under the radar, despite being vital for hundreds of enzymes and transcription factors involved in immunity, antioxidant defense, and DNA repair. A surprisingly large segment of the population may not get enough – an estimated 10% of U.S. individuals consume less than half the recommended zinc intake, putting them at risk of deficiency. In this episode, Prof. Emily Ho discusses how even mild zinc insufficiency can impair immune function, promote chronic inflammation, and accelerate aspects of aging. She delves into the concept of "inflammaging" – the chronic, low-grade inflammation that develops with age – and explains how inadequate zinc status can aggravate this process. The conversation also highlights emerging research on zinc's role in DNA integrity and how restoring zinc levels can reverse certain damage, underscoring zinc's broader significance in healthy aging and disease prevention. Overall, this episode provides a deep scientific look at why maintaining adequate zinc status is crucial for immune resilience and mitigating age-related inflammatory and oxidative damage. About the Guest Emily Ho, PhD is the Director of the Linus Pauling Institute and professor in the College of Health at Oregon State University. Her research focuses on understanding the mechanisms by which nutrient status and healthy foods affect the initiation and/or progression of chronic diseases such as cancer. Her work has helped drive dietary requirements and recommendations for micronutrients such as zinc for communities with susceptibility to poor nutrition. Timestamps [02:10] Interview begins [03:58] The roles of zinc [06:31] Zinc deficiency and insufficiency [14:26] Prevalence and risk factors of zinc deficiency [21:12] Zinc and age-related inflammation [29:39] Zinc's impact on chronic diseases [31:20] Practical advice on zinc supplementation [41:14] Final thoughts Related Resources Go to episode page (includes related research) Join the Sigma email newsletter for free Subscribe to Sigma Nutrition Premium Enroll in the next cohort of our Applied Nutrition Literacy course Linus Pauling Institute (LPI) Website Micronutrient Information Center Top 10 Micronutrients for Healthy Aging Webinars on LPI YouTube
Transcribe →#564: Is Protein's Appetite-Suppressing Power Overstated?
May 27, 202501:11:19Tap to summarizeIn this episode, we take a deep dive into the commonly held belief that protein is the most satiating macronutrient. It's an idea that shows up frequently in both clinical guidance and popular nutrition discourse: if you want to feel fuller, eat more protein. But how robust is that claim when you drill into the details of the evidence? To explore this, Alan and Danny examine the complex interplay between protein intake, satiety, and energy intake. We look at both historical and recent literature, including work from Kevin Hall's group, that raises important questions about how much of protein's supposed appetite-suppressing effect is due to the protein itself versus other influential variables—such as eating rate, food texture, and energy density. This is an important topic, not just for academic curiosity, but for its practical implications. If our assumptions about protein and satiety are oversimplified or overstated, that has knock-on effects for how we design diets aimed at appetite regulation, weight management, or obesity prevention. So whether you're a researcher, a clinician, or simply someone interested in understanding the mechanisms behind how we eat, this episode aims to provide clarity on where the science currently stands—and where it might be leading. Timestamps [03:18] The impact of protein on satiety [04:49] Historical context of protein and satiety [07:30] Mechanisms of protein-induced satiety [16:31] Research methods and measurements [21:39] Studies on protein and satiety [27:51] Analyzing specific studies [35:51] Understanding high protein meals and their effects [37:31] Acute vs. chronic effects of high protein intake [45:59] Other meal characteristics [53:21] Real-world implications of protein intake [01:01:19] Summarizing the impact of protein on satiety Related Resources Subscribe to Sigma Nutrition Premium Join the Sigma email newsletter for free Enroll in the next cohort of our Applied Nutrition Literacy course Go to episode page Related studies: Fazzino et al., Nature Food, volume 4, pages144–147 (2023) Weigle et al., Am J Clin Nutr. 2005 Jul;82(1):41-8 Smeets et al., J Nutr. 2008 Apr;138(4):698-702 Blatt et al., J Am Diet Assoc. 2011 Feb;111(2):290-4.
Transcribe →#563: The Financialization of the Food System – Prof. Martin Caraher
May 20, 202500:44:27Tap to summarizeGlobal food systems have been increasingly subjected to financial speculation, leading to adverse consequences for growers, consumers, and public health. But what are the systemic vulnerabilities that impact food security, equitable access to nutritious food, and the broader socio-political frameworks influencing these outcomes? Understanding the financial mechanisms shaping food production and distribution is highly relevant for health professionals, policy makers, and researchers concerned with nutrition, equity, and global health systems. This episode urges a critical re-evaluation of current food policies and invites consideration of more ethical, resilient approaches to safeguarding food systems. Professor Martin Caraher is Emeritus Professor of Food and Health Policy at the Centre for Food Policy, City St. Georges, University of London. His research encompasses food poverty, food security, the role of food aid, and the broader implications of food systems on public health. Timestamps [01:12] Financialization of food: an overview [05:27] Speculation and its impact on food prices [13:10] Global food security and policy responses [17:20] Corporate concentration in food systems [34:03] Potential solutions and future directions Related Resources Go to episode page Prof. Caraher's Recommended Reading List Join the Sigma email newsletter for free Subscribe to Sigma Nutrition Premium Enroll in the next cohort of our Applied Nutrition Literacy course Episode #344: Prof. Martin Caraher – Food Poverty & Food Aid Provision X: @MartinCaraher and @NutritionDanny
Transcribe →SNP40: Do Seed Oils Cause Inflammation & Chronic Disease?
May 13, 202500:14:48Tap to summarizeSeed oils have recently become a hotly debated topic in nutrition, fueled by sensational claims on social media. In this episode, the central theme is examining whether seed oils are truly harmful or if they've been unjustly demonized. The discussion tackles prevalent claims – that seed oils drive inflammation, oxidation, and chronic disease – and compares them against the current scientific evidence. This is highly relevant to nutrition science and clinical practice today, as many patients and practitioners are encountering conflicting information about vegetable oils. By exploring the origins of seed oils, their biochemical effects, health outcome data, and the misinformation ecosystem, the episode aims to clarify how omega-6 rich seed oils fit into a healthy diet and what evidence-based guidelines say. Timestamps 01:00 Understanding terms: PUFA, Linoleic Acid, Omega-6 05:20 Do seed oils cause inflammation? 12:44 Omega-3 and omega-6 16:43 Inflammatory markers and linoleic acid 19:22 Oxidation and cooking oils 26:25 Refining processes and health concerns 30:32 Health outcomes and polyunsaturated fats 35:18 Evidence cited by anti-seed oil proponents 43:48 Conclusions Related Resources Join the Sigma email newsletter for free Subscribe to Sigma Nutrition Premium Enroll in the next cohort of our Applied Nutrition Literacy course Sigma Statement: Seed Oils on Trial: Is the Panic Justified? Related podcast episodes: 502: Sydney Diet-Heart Study – Is Linoleic Acid Causing Heart Disease? 504: Vegetable Oil vs. Saturated Fat – Analysis of the LA Veterans Study 505: Oslo Diet-Heart Study: Cholesterol-lowering Diets & Cardiovascular Events 329: Diet & Inflammation
Transcribe →#562: How to Detoxify Yourself – Quack Asylum Special
May 6, 202501:20:51Tap to summarizeIn this Quack Asylum episode, Danny and Alan critically examine the claims surrounding "detoxification protocols" – specialized diets, cleanses, or supplements marketed to eliminate toxins from the body for better health. The central theme is whether these detox plans actually improve health outcomes or if they're built on pseudoscience and fear. Many alternative health proponents argue that modern life exposes us to countless toxins that accumulate in our bodies, causing chronic diseases, and thus we must undergo periodic detox regimens to cleanse ourselves. There is genuine concern about environmental pollutants and chemicals – indeed, numerous substances in our food, water, and air can be harmful at sufficient doses. Nutritional science also recognizes that certain nutrients (e.g. vitamins, antioxidants) play roles in the body's natural detox pathways. However, there's a large gap between acknowledging real toxic exposures versus endorsing commercial "detox" diets or products. Many people, including health professionals, encounter patients or clients interested in detox plans, so understanding the science (or lack thereof) behind these claims is important. Timestamps [03:20] Claim 1 – Mark Hyman [06:10] The purpose of today's episode [08:22] Claim 2 – Chris Kresser [11:30] Detoxification Pathways in the Body [25:46] Glutathione, heavy metals and other nutrients [50:30] Do nutrients support detox pathways [55:20] Unhinged claims: Mold and mycotoxin toxicity [01:04:54] One more unhinged claim [01:09:10] Conclusions Related Resources Subscribe to Sigma Nutrition Premium Join the Sigma email newsletter for free Go to episode page Enroll in the next cohort of our Applied Nutrition Literacy course
Transcribe →#561: Emulsifiers in the Modern Diet: Health Risk or Harmless Additive?
Apr 29, 202500:50:41Tap to summarizeEmulsifiers are a ubiquitous component of the modern food supply, found in everything from salad dressings and dairy products to pastries and sauces. Traditionally regarded as safe by regulatory agencies, emulsifiers play a vital role in enhancing the texture, stability, and shelf-life of countless processed foods. Yet, in recent years, emerging research has prompted a reevaluation of this assumption, raising intriguing questions about whether regular consumption of these additives might have previously overlooked health consequences. Recent epidemiological studies have suggested possible associations between higher emulsifier intake and chronic health issues. Concurrently, mechanistic research has provided some biological pathways through which emulsifiers could disrupt gut health. This episode aims to critically examine the scientific literature surrounding dietary emulsifiers, differentiating credible evidence from speculation, and outlining what can—and cannot—be concluded about their potential risks. Timestamps [01:18] Emulsifiers in food: definition, function, and common uses [05:15] Regulatory approval and traditional safety evaluations [09:32] Epidemiological studies on emulsifiers: nutriNet-santé cohort [14:55] Emulsifiers and cardiovascular disease risk [26:12] Emulsifiers and type 2 diabetes risk [30:01] Emulsifiers and cancer risk [35:05] Mechanistic insights: emulsifiers, gut health, and inflammatory bowel disease (IBD) [47:15] Practical recommendations and clinical implications Related Resources Subscribe to Sigma Nutrition Premium Go to episode page (with study links) Join the Sigma email newsletter for free Enroll in the next cohort of our Applied Nutrition Literacy course
Transcribe →#560: Neurodiversity & Nutrition: Choline, ADHD, Dyslexia, and Beyond – Emma Derbyshire, PhD
Apr 22, 202500:45:55Tap to summarizeNutrition is increasingly being considered as a modifiable factor that may influence neurodevelopmental outcomes. While severe deficiencies in certain nutrients are known to have dramatic effects, there is growing interest in the potential impact of more subtle insufficiencies — particularly during critical windows such as pregnancy, infancy, and early childhood. In conditions like ADHD, dyslexia, and autism spectrum condition (ASC), questions have been raised around whether specific nutrients may play a role in cognitive performance, attention, or learning. Could low choline intake be a contributing factor to altered brain function? Are individuals with neurodevelopmental conditions more likely to have different nutrient needs or metabolic profiles? And how might practical dietary strategies fit into a broader management approach? In this episode, Dr. Emma Derbyshire discusses the evidence on choline and other brain-related nutrients in the context of neurodiversity. Timestamps [02:02] Guest background [05:38] Choline: what it is and why it matters [07:26] Research challenges: measuring choline and study design issues [10:49] Maternal intake: choline's role in fetal brain development [14:24] Choline & neurodevelopmental disorders (ADHD, ASC, dyslexia) [17:14] The choline gap: intake vs. requirements [23:05] Supplementation: adequacy vs. excess and safety concerns [25:05] Food sources: choline in the diet & intake planning [30:14] Nutrition as a tool in ADHD and dyslexia management [38:45] Other key nutrients (omega-3s, iron, iodine, magnesium, water) Related Resources Go to episode page Join the Sigma email newsletter for free Subscribe to Sigma Nutrition Premium Enroll in the next cohort of our Applied Nutrition Literacy course Book: Nutrition for ADHD and Dyslexia: Unlocking the Potential for Learning and Wellbeing Dr. Derbyshire's website: https://www.nutritional-insight.co.uk/
Transcribe →Do Lipids Increase During Weight Loss? (SNP39)
Apr 15, 202500:20:03Tap to summarizeThis is a segment from 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. Questions Answered in This Episode [02:00] Why does the Mediterranean diet emphasize monounsaturated fats over polyunsaturated fats when the latter seem more beneficial for heart health? [08:48] What dietary patterns or foods best support strength and recovery in premenopausal women, especially on a plant-based diet? [20:33] Are there specific foods or supplements that help regenerate or protect connective tissue in conditions like EDS? [28:39] What does the current evidence say about the keto diet during cancer treatment, and are there specific cancers where it might be beneficial? [43:31] What are the biochemical processes behind fat loss, including fat mobilization, transport, and any potential short-term cardiovascular risks? [59:48] What is the most effective system for organizing, structuring, and retrieving accumulated knowledge over time? [1:10:37] Do you agree with Dr. Tom Dayspring that a significant percentage of people are hyper-absorbers of dietary cholesterol, making food cholesterol impactful for them? [1:14:35] Is consuming 2g of protein per pound of body weight safe if calorie intake is high and well-balanced? Links Subscribe to Sigma Nutrition Premium Go to sigmanutrition.com
Transcribe →#559: Skin Health & Nutrition – Thivi Maruthappu, PhD
Apr 8, 202500:45:29Tap to summarizeThe intersection of nutrition, dermatology, and skin health is an area of growing interest, yet one that remains riddled with misinformation and oversimplified claims. The influence of dietary patterns, specific nutrients, and lifestyle factors on conditions such as acne, eczema, psoriasis, and skin aging has been widely debated, with varying levels of evidence supporting different interventions. While some nutritional strategies may play a role in optimizing skin health, the challenge lies in distinguishing practical, evidence-based approaches from overstated or anecdotal claims. A significant issue in this space is the naturalistic fallacy—the belief that diet alone can replace medical treatments, or that conventional dermatological interventions should be avoided in favor of "natural" approaches. This has led to widespread vilification of certain foods, such as dairy, gluten, and sugar, despite a lack of strong supporting data. Similarly, supplements and probiotics are often promoted with broad claims, while their actual efficacy is highly context-dependent—varying based on individual nutrient status, disease severity, and baseline dietary intake. In this episode, Dr. Thivi Maruthappu, a consultant dermatologist and researcher in nutritional dermatology, joins Danny Lennon to explore the current state of evidence in this field. Guest Information Dr Thivi Maruthappu MA PhD FRCP ANutr is a consultant dermatologist, nutritionist and leading researcher. As the UK's first and only dual-qualified dermatologist and nutritionist, her pioneering expertise bridges the gap between diet and skin health. Dr Thivi continues to work in the NHS and has her own practice based at London's renowned Cleveland Clinic. Dr Thivi studied Medicine at Oxford University and completed Dermatology training in London. She undertook a PhD to understand the links between our skin and internal health and this research featured in top tier scientific journals. She is one of a handful of dermatologists to have completed training in severe eczema and psoriasis during a fellowship at St John's Institute of Dermatology, London and achieved a Certificate in Nutrition Science from Stanford Medical School, USA. Timestamps [02:52] Start of interview [03:37] Dr. Maruthappu's background and expertise [05:57] Sunscreen and skin health: myths and facts [12:15] Effective skincare ingredients [16:07] The role of nutrition in skin health [20:25] Dairy and skin conditions [24:10] Collagen supplements: do they work? [27:45] Probiotics for skin health [31:35] Research outcomes and challenges [35:20] Practical applications in clinical practice [43:05] Key ideas segment (premium-only) Related Resources Join the Sigma email newsletter for free Subscribe to Sigma Nutrition Premium Enroll in the next cohort of our Applied Nutrition Literacy course Dr. Maruthappu's website
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