Zinc 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.

• [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

• Go to episode page (includes related research)
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• Linus Pauling Institute (LPI) Website
• Micronutrient Information Center
• Top 10 Micronutrients for Healthy Aging
• Webinars on LPI YouTube

In 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.

• [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

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• 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.

Global 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.

• [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

• Go to episode page
• Prof. Caraher’s Recommended Reading List
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• Episode #344: Prof. Martin Caraher – Food Poverty & Food Aid Provision
• X: @MartinCaraher and @NutritionDanny

Seed 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.

• 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

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• 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

In 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.

• [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

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Emulsifiers 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.

• [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

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Nutrition 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.

• [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)

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• Book: Nutrition for ADHD and Dyslexia: Unlocking the Potential for Learning and Wellbeing
• Dr. Derbyshire’s website: https://www.nutritional-insight.co.uk/

This 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.

• [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?

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