In this episode, I sit down with Dr David Katz to unpack the newly released 2025 US Dietary Guidelines and what they mean for public health. David doesn’t hold back. He describes the process as a subordination of science to ideology, raising serious concerns about how evidence was handled, what was emphasised, and what was sidelined.
We explore where the guidelines diverge from the work of the Dietary Guidelines Advisory Committee, whether industry influence is really the issue, and what actually matters for everyday people trying to eat well. If you’re feeling confused by conflicting headlines about protein, saturated fat, seed oils, and dairy, this conversation brings us back to first principles.
What We Cover
- Why David’s first reaction to the new guidelines was “hypocrisy”
- The difference between the Advisory Committee’s scientific review and the final political document
- The emphasis on eating more meat and protein: what does the evidence actually say?
- Why “eat real food” is good advice, but not a new breakthrough
- Whether most Americans truly need more protein
- The internal contradictions around saturated fat and full-fat dairy
- The truth about seed oils, essential fatty acids, and olive oil
- Dairy fat: is full-fat actually better, and compared to what?
- Why legumes may be the most underrated food group for longevity
- What the Blue Zones teach us about fat quality, fibre, and dietary balance
At the heart of this conversation is a simple reminder. Nutrition is endlessly complex in the details, but profoundly simple in principle. Eat real food, mostly plants, in sensible balance. That message has not changed, and it is unlikely to.
You can connect with Dr David Katz on LinkedIn, Facebook, and X (Twitter). To learn more about his work, visit davidkatzmd.com, explore Diet ID, and discover the True Health Initiative.
- Intro (00:00)
- Initial Reactions to the New Dietary Guidelines (01:36)
- Political Influences on Dietary Guidelines (08:54)
- Specific Departures from Evidence-Based Recommendations (18:58)
- Historical Context and Modern Diet Quality (33:55)
- Protein Quality and Public Health (41:10)
- Regenerative Agriculture and Legumes (46:29)
- Understanding Fats in Our Diet (50:10)
- Contradictions in Dietary Guidelines (01:01:22)
- Dairy Consumption: Pros and Cons (01:10:20)
- Personalizing Your Diet for Optimal Health (01:19:25)
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More about David L. Katz
David L. Katz, MD, MPH, FACPM, FACP, FACLM is a specialist in Internal Medicine, Preventive Medicine/Public Health, and Lifestyle Medicine, with particular expertise in nutrition.
He earned his BA at Dartmouth College (1984); his MD at the Albert Einstein College of Medicine (1988); and his MPH from the Yale University School of Public Health (1993). He completed sequential residency training and board certification in Internal Medicine (1991) and Preventive Medicine/Public Health (1993).
Katz is the founder and former director of Yale University’s Yale-Griffin Prevention Research Center (1998-2019), where he secured and managed roughly $40M in research funding. He is Past President of the American College of Lifestyle Medicine; Founder of the non-profit True Health Initiative; and Founder and CEO of Diet ID, Inc. He has served as Chief Medical Officer for *Tangelo,* an award-winning food-as-medicine company. He serves as a senior science advisor to Blue Zones and Blue Zones Health.
Katz held faculty positions at the Yale schools of Medicine, Public Health, and Nursing. He cared for patients in the context of primary care Internal Medicine and an innovative model of Integrative Medicine for roughly 30 years, receiving awards for both clinical care and bedside teaching. He served as a residency director in both Preventive Medicine and evidence-based Integrative Medicine. He was the lead architect of the nation’s first fully accredited, combined training program in Internal Medicine and Preventive Medicine. Katz was the inaugural editor-in-chief of the peer-reviewed journal, Childhood Obesityserving in that role for 5 years.
He is a Fellow of the American College of Preventive Medicine; the American College of Physicians; the American College of Lifestyle Medicine; and Morse College, Yale University.
The recipient of numerous awards for teaching, writing, and contributions to public health, Katz was a 2019 James Beard Foundation Award nominee in health journalism, has been a widely supported nominee for the position of U.S. Surgeon General, and has received three honorary doctorates. He is a 2023 recipient of a Lifetime Achievement Award from the Doctors’ World Galaand the 2024 recipient of the President’s Award from the American College of Lifestyle Medicine. He was inducted into Sigma Xithe scientific research honor society, in 2025.
Katz has an extensive media portfolio, having served as a nutrition columnist for O, the Oprah Magazine; an on-air contributor for ABC News/Good Morning America; and with appearances on most major news programs and contributions to most major magazines and leading newspapers, including OpEds in the New York Times and Wall Street Journal. He is one of the original 150 “Influencers” selected by LinkedIN, and has a social media following of nearly one million.
He holds multiple U.S. patents; has roughly 250 peer-reviewed publications; has published many hundreds of on-line and newspaper columns; and has authored/co-authored 19 books to date including multiple editions of leading textbooks in nutrition, preventive medicine, and epidemiology. His most recent book for a general audience, How to Eatco-authored with Mark Bittman, was a 2021 IACP Awards finalist.
His career-long focus has been the translation of science into action for the addition of years to life, and life to years, and on the confluence of human and planetary health.
On the COVID pandemic, he advocated consistently for a policy of total harm minimization (https://www.truehealthinitiative.org/covid/) by means of risk-stratified interdiction efforts- and for addressing the “prior pandemic” of cardiometabolic disease that contributes so much to acute risk. These views were extensively covered in the New York Times. His commentary on lessons in the pandemic in the American Journal of Health Promotion was recognized among the journal’s “Best Papers of 2024.”
Katz has presented at conferences in all 50 U.S. states and in multiple countries on six continents. Represented by the Harry Walker Agency, he has been recognized by peers as the “poet laureate of health promotion.”
He and his wife, Catherine, live in Connecticut. They have five grown children.
