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

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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