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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 distills what the science actually shows and what remains uncertain.

Whether you have followed throughout the year or are tuning in for the first time, this episode provides a concise synthesis of what truly mattered and what these ideas imply for how we interpret nutrition science moving forward.

• [02:23] Christopher Gardner, PhD – How dietary guidelines are shaped, misused, and what the evidence really supports.
• [13:10] Marie-Pierre St-Onge, PhD – The bidirectional relationship between sleep quality, circadian timing, and diet.
• [20:03] Duane Mellor, PhD – Rethinking ultra-processed foods: mechanisms, misconceptions, and policy realism.
• [29:26] Samuel Dicken, PhD – The UPDATE trial and what nutrient-matched processing tells us about satiety and intake.
• [35:37] Ian Mudway, PhD – Microplastics, pollution, and why evidence must outrun public fear.
• [43:46] Martin Caraher, PhD – The financialization of food systems and its impact on inequality and diet quality.

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