Show Notes
Today, we’re diving into autoimmunity—what it actually is, why it happens, and how ultra-processed foods may be contributing to the problem. Autoimmune disease is often misunderstood. Some will tell you diet has nothing to do with it. Others claim diet is the cure. The truth is more nuanced—and that’s exactly what we explore in this episode. You’ll learn:
What autoimmunity really is (and why it’s a case of mistaken identity) How inflammation and the immune system interact The critical role of gut health and the microbiome How ultra-processed foods disrupt intestinal integrity and immune signaling Why stress and hyper-palatable foods create a harmful cycle A practical experiment you can try to see how diet impacts your own biomarkers
This isn’t about selling supplements or pushing extremes. It’s about understanding the science so you can make informed decisions about your health. As always, this episode is backed by scientific literature. Full citations are included below, with abbreviated versions available on shorter clips. If you’re dealing with autoimmune symptoms—or just want to better understand how food impacts your immune system—this episode is for you.
Full citation list: Hall KD, et al. “Ultra-Processed Diets Cause Excess Calorie Intake and Weight Gain: An Inpatient Randomized Controlled Trial of Ad Libitum Food Intake.” Cell Metabolism, 2019. Supports the formulation argument: UPF intake increased spontaneous calorie intake and weight gain even with diets matched for presented calories, sugar, fiber, sodium, and macronutrients. This is your anchor for “hyper-palatability and formulation change physiology, not just psychology.” Narula N, et al. “Association of Ultra-Processed Food Intake With Risk of Inflammatory Bowel Disease: Prospective Cohort Study.” BMJ, 2021. Best human disease-level citation for the episode. Supports the claim that higher UPF intake is associated with greater IBD risk, making the gut-immune link clinically meaningful rather than purely theoretical. Chassaing B, et al. “Randomized Controlled-Feeding Study of Dietary Emulsifier Carboxymethylcellulose Reveals Detrimental Impacts on the Gut Microbiota and Metabolome.” Gastroenterology, 2022. Best emulsifier paper for human translation. Supports the claim that CMC can perturb the microbiota and metabolome and may contribute to barrier-hostile gut ecology in susceptible individuals. Daniel N, et al. “Human Intestinal Microbiome Determines Individualized Responses to Dietary Emulsifier Carboxymethylcellulose.” Cellular and Molecular Gastroenterology and Hepatology, 2024. Useful nuance paper. Supports the point that emulsifier sensitivity is not identical across all people and that host-microbiome context matters. Shil A, et al. “Artificial Sweeteners Disrupt Tight Junctions and Barrier Function in the Intestinal Epithelium Through Activation of the Sweet Taste Receptor T1R3.” Nutrients, 2020. Best citation for the “sugar-free does not mean barrier-neutral” point. Supports direct epithelial barrier effects of common artificial sweeteners in experimental models. Peng L, et al. “Butyrate Enhances the Intestinal Barrier by Facilitating Tight Junction Assembly via Activation of AMP-Activated Protein Kinase in Caco-2 Cell Monolayers.” Journal of Nutrition, 2009. Classic mechanistic citation for butyrate. Supports the claim that loss of fermentable fiber and reduced butyrate production can weaken barrier function. Kumar KP, et al. “The Interplay Between the Microbiota, Diet and T Regulatory Cells in Maintaining Intestinal Homeostasis.” Frontiers in Microbiology, 2023. Useful for the tolerance language. Supports the argument that diet and microbial metabolites shape Treg biology and mucosal tolerance. Haase S, et al. “Sodium Chloride Triggers Th17 Mediated Autoimmunity.” Frontiers in Immunology, 2019. Key citation for high salt and autoimmune-prone immune skewing. Supports the claim that excess sal
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