#589: Causal Inference in Nutrition Science – Daniel Ibsen, PhD
Release Date: 12/30/2025
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Sigma Nutrition Radio
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#612: Does Sweet Taste Exposure Actually Develop Preference? – Prof. Katherine Appleton
Sigma Nutrition Radio
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Sigma Nutrition Radio
This is a Premium-exclusive episode. Go to the Premium feed to listen. Or subscribe to . Blood glucose is easy to measure, but not always easy to interpret. This Premium-only episode brings together insights from several previous guests to examine blood glucose responses in more detail. We discuss the misuse of clinical thresholds, the difference between OGTT results and free-living CGM data, and whether “flatter” glucose curves are actually better in normoglycemic people. The episode also covers when repeated high glucose excursions may be worth investigating, how...
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#610: Rock, Paper, Salmon – Errors in Interpreting Food Substitution Models
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Performance nutrition in elite sport is often discussed in terms of meal plans, supplements, and macronutrient targets. However, effective practice in professional environments depends just as much on education, trust, communication, and the ability to translate scientific principles into decisions athletes can act on under real-world constraints. In this episode, Dr James Morehen discusses his work across elite rugby, football, and combat sports, with particular attention to the demands of professional rugby. The conversation explores how practitioners support athletes in a high-impact...
info_outlineThis episode explores how asking better questions and using stronger methods can resolve much of the confusion in nutrition science. Dr. Daniel Ibsen discusses why nutrition research often produces conflicting results and how careful methodological thinking can clarify true diet-disease relationships.
Nutrition science has unique challenges – diets are complex, people self-report their food intake imperfectly, and we can’t easily run long-term diet experiments on people. Dr. Ibsen explains how embracing concepts like food substitution analysis, the “target trial” framework, and objective dietary assessment can strengthen evidence.
The episode centers on methodological insights that make nutrition research more reliable and actionable. Key themes include defining dietary comparisons explicitly (the “compared to what?” question), considering people’s starting diets, and using causal inference techniques to design better studies.
Daniel B. Ibsen is an epidemiologist and nutritional scientist whose work bridges rigorous causal inference methods with real-world diet and cardiometabolic disease research. He is an Associate Professor at Aarhus University, Denmark.
Timestamps
- [00:13] Introduction to the topic
- [03:23] Interview start
- [08:02] The importance of asking the right questions in nutrition science
- [22:18] Understanding causal inference in nutrition
- [28:58] Challenges and approaches in nutrition epidemiology
- [32:07] Mimicking dietary interventions in studies
- [32:55] Target trial framework
- [39:52] Objective vs. subjective dietary assessment
- [47:01] Why causal effects of ultra-processed foods cannot be identified
Links/Resources:
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