Why Doctors Aren’t Taught Nutrition — Dr. Nick Norwitz Exposes The Truth

Participants: Dr. Eric Westman (host) and Dr. Nick Norwitz (guest)

Norwitz’s background & health story

• Undergraduate at Dartmouth (cell biology & biochemistry); PhD at Oxford; admitted to Harvard Medical School.
• Developed severe inflammatory bowel disease with debilitating GI symptoms.
• Attempted standard medical approaches without adequate relief.
• Adopted a Mediterranean-leaning ketogenic diet (fatty fish, olive oil, vegetables; low carbohydrate) and experienced rapid, substantial improvement and recovery.

Why doctors aren’t taught much nutrition

• Medical training is designed primarily for diagnosing and treating disease with medications and procedures; prevention and nutrition receive little curricular time.
• “Evidence-based medicine” is valuable but can be limited by:
  • Overreliance on narrow hierarchies that discount mechanistic and patient-level evidence.
  • Institutional incentives (e.g., drug-centric frameworks) that don’t translate well to diet and lifestyle.
• Practical nutrition education is often missing, leaving clinicians without clear frameworks or tools.

Models of obesity & metabolism discussed

• Calories In/Calories Out (CICO): Critiqued as a near tautology—describes weight change but offers limited mechanistic guidance.
• Carbohydrate-Insulin Model (CIM): Presented as an alternative framework emphasizing hormonal regulation (insulin) and carbohydrate quality/quantity as drivers of fat storage and appetite.

Clinical practice considerations raised

• Many patients achieve meaningful improvements (weight, metabolic health) with low-carb/keto patterns; individual responses vary.
• Randomized trials and mechanistic studies both matter, but patients ultimately need safe, n=1 experimentation with clinician support.
• Clinicians are comfortable prescribing FDA-approved drugs (e.g., GLP-1 agonists, SGLT2 inhibitors), but comparable, scalable guidance for nutrition is rarely taught despite potential benefit.

Statins, GLP-1, and emerging evidence

• A highlighted human controlled trial reported that statin therapy markedly reduced circulating GLP-1 levels over ~16 weeks, raising questions for primary prevention scenarios with isolated LDL elevation.
• Framed as hypothesis-generating rather than definitive clinical guidance; underscores the need for open, nuanced discussion about trade-offs.

Westman’s reflections (host)

• Early clinical encounters with patients succeeding on very low-carb or carnivore-leaning diets challenged prior assumptions.
• Longstanding experience suggests such diets can be safe and effective for many, but academic acceptance lagged amid debates over mechanisms.

Takeaways

• Nutrition is underemphasized in medical education relative to its potential impact on chronic disease.
• Competing models (CICO vs. CIM) shape how clinicians and researchers interpret evidence and craft guidance.
• More practical, patient-centered nutrition training and better translational frameworks are needed alongside pharmacologic options.

Papers referenced in the discussion (DOIs)

• Carbohydrate-Insulin Model overview: Ludwig DS et al. “The carbohydrate-insulin model: a physiological perspective on the obesity pandemic.” Am J Clin Nutr (2021). https://doi.org/10.1093/ajcn/nqab270
• Statins & GLP-1 (human controlled trial): She J et al. “Statins aggravate insulin resistance through reduced blood glucagon-like peptide-1 levels in a microbiota-dependent manner.” Cell Metabolism (2024). https://doi.org/10.1016/j.cmet.2023.12.027
• Low-carb/keto for T2D (Virta 2-year trial referenced): Athinarayanan SJ et al. “Long-Term Effects of a Novel Continuous Remote Care Intervention Including Nutritional Ketosis for the Management of Type 2 Diabetes: A 2-Year Non-randomized Clinical Trial.” Front Endocrinol (2019). https://doi.org/10.3389/fendo.2019.00348