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David Ludwig MD, PhD @davidludwigmd.bsky.social · 2d

Will targeting "ultra-processed food" in national nutrition policy make Americans (and the rest of the world) healthier?

I argue there is a better way
wapo.st/3WuPHGJ

Opinion | Targeting ultra-processed food repeats America’s missteps on nutrition

MAHA blames this food group for chronic disease. Nutrition science isn’t so simple.

wapo.st

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Reposted by David Ludwig MD, PhD

PennMedCSO @pennmedcso.bsky.social · 11d

In @natmed.nature.com, Mary Putt (@dbei-upenn.bsky.social), @davidludwigmd.bsky.social & Walter Willett (@hsph.harvard.edu) discuss concerns for the validity of short-term dietary crossover trials www.nature.com/articles/s41...

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David Ludwig MD, PhD @davidludwigmd.bsky.social · 20d

Target "ultra-processed foods" to tackle the chronic disease epidemic .... What could possibly go wrong? My 50 min convo with Nick Norwitz www.youtube.com/watch?v=JAPg...

This Will Change Your Mind on Ultra-Processed Foods (Harvard MD PhDs Discuss)

YouTube video by Nick Norwitz

www.youtube.com

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David Ludwig MD, PhD @davidludwigmd.bsky.social · 28d

When you have 50 min ...

The investigative journalist Gary Taubes and I discuss the notion of ultra-processed foods, the sorry state of nutrition research ... and how we can inch toward truth when scientific paradigms collide.
www.youtube.com/watch?v=PfOb...

The Ultra-Processed Food Debate: Science, Bias, & Truth

YouTube video by Metabolic Mind

www.youtube.com

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David Ludwig MD, PhD @davidludwigmd.bsky.social · 29d

The hotter it gets, the more sugar we consume ... mainly in the form of sugary drinks.

👉Let's find other ways to keep cool
www.nature.com/articles/s41...

Rising temperatures increase added sugar intake disproportionately in disadvantaged groups in the USA - Nature Climate Change

Few studies have evaluated how climate change may affect dietary habits and nutritional health. Here, using transaction data in the USA, the authors show that added sugar consumption increases with te...

www.nature.com

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David Ludwig MD, PhD @davidludwigmd.bsky.social · Sep 4

Should national nutrition policy target "Ultra-Processed Foods" as many advocate?

I consider concerns in @nejm.org

Like 'The Emperor's New Clothes'

👉We're rolling out a red carpet, but the evidence is threadbare!

NEJM: www.nejm.org/doi/10.1056/...

BLOG (no paywall) medium.com/@davidludwig...

Ultraprocessed Food on an Ultrafast Track | NEJM

The Nova food-classification system has advanced efforts to address modern diets of highly processed foods. But it’s unclear whether it can be codified at a national level to support public health.

www.nejm.org

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David Ludwig MD, PhD @davidludwigmd.bsky.social · Jun 7

Certified for 1-oar rowing today in Hellerup, Denmark (where we live part time).

I don't believe I have Viking ancestors, but if I do, they would be proud. 😀

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David Ludwig MD, PhD @davidludwigmd.bsky.social · Jun 5

My 1-hour (40 min on 1.5 x 😀) deep dive on the diets, nutrition research, and where we go from here ... with journalist Gary Taubes, hosted by @metabolicmind.bsky.social

The Truth About Nutrition Science: Is The Government Getting it Wrong?

YouTube video by Metabolic Mind

www.youtube.com

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David Ludwig MD, PhD @davidludwigmd.bsky.social · Jun 3

Debating the Carbohydrate-Insulin Model with John Speakman in Cell Metabolism.

Letter-to-the-Editor (open access) authors.elsevier.com/a/1lCYr5WXUl...

Reply www.cell.com/cell-metabol...

David Ludwig MD, PhD @davidludwigmd.bsky.social · May 26

Avoid carbs to prevent malaria?

Preliminary evidence suggests maybe so ...
www.nature.com/articles/s42...

β-hydroxybutyrate inhibits Plasmodium falciparum development and confers protection against malaria in mice - Nature Metabolism

A ketogenic diet and the ketone body β-hydroxybutyrate are shown to confer resistance to malaria in mice by inducing metabolic reprogramming in Plasmodium parasites, suggesting a dietary strategy for ...

www.nature.com

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David Ludwig MD, PhD @davidludwigmd.bsky.social · May 25

“Pathological” science?

To solve the chronic disease epidemics, we need to get the research right.

Gary Taubes on the failure of nutrition science to correct fatally flawed diet trials … and avoid these blunders in the first place.

NIH Has A Nutrition Problem (Part 2 )

If you want to demonstrate that a plant-based diet is better than a ketogenic diet (or that ultra-processed food makes us overeat), these critical design flaws will help

substack.com

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David Ludwig MD, PhD @davidludwigmd.bsky.social · May 19

Italian professional societies consensus report on diet and skin disease.

Data are preliminary but promising:

👉Low-carb ketogenic diet may help acne, psoriasis
link.springer.com/article/10.1...

Medical Nutrition Therapy in Dermatological Diseases: A Joint Consensus Statement of the Italian Association of Dietetics and Clinical Nutrition (ADI), the Italian Society of Dermatology and Sexually ...

Summary Dermatological diseases such as acne, hidradenitis suppurativa (HS), and psoriasis are driven by chronic inflammation and oxidative stress. Emerging evidence highlights the role of nutrition i...

link.springer.com

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David Ludwig MD, PhD @davidludwigmd.bsky.social · May 14

NIH Nutrition Research Takes it on the Chin

Gary Taubes' deep dive into the largest nutrition trial in years.

#DesignedToFail
uncertaintyprinciples.substack.com/p/nih-nutrit...

NIH Nutrition Research Takes it on the Chin

A "top" nutrition researcher exits, followed by two damning articles challenging his studies and claiming that a flagship $170 million NIH initiative is "designed to fail."

uncertaintyprinciples.substack.com

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Reposted by David Ludwig MD, PhD

Center for Health Incentives and Behavioral Economics @pennchibe.bsky.social · May 12

What diet works best to prevent obesity, diabetes, cardiovascular disease, cancer and Alzheimer’s? Answers remain elusive...But why? The problem may be rooted in poorly designed nutrition research. @davidludwigmd.bsky.social chibe.upenn.edu/news/short-t...

Short-term diet trials are designed to fail - Center for Health Incentives and Behavioral Economics (CHIBE)

This article critiques short-term diet trials, arguing they are inadequate for understanding nutrition's impact on chronic disease.

chibe.upenn.edu

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Reposted by David Ludwig MD, PhD

David Ludwig MD, PhD @davidludwigmd.bsky.social · Apr 27

Designed to Fail:

Why short-term diet trials cannot solve the epidemics of chronic disease.

👉New blog post (no paywall)

Designed to Fail: Why Short-term Diet Trials Cannot Solve the Epidemics of Chronic Disease

A version of this essay was published in STAT News First Opinion on April 22

davidludwigmd.medium.com

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Reposted by David Ludwig MD, PhD

The BMJ @bmj.com · Apr 30

The effects of an intervention may take time to develop and persist after discontinuation, producing wash-in and washout effects that threaten trial validity.

This article describes the nature of this bias in nutrition research as an illustrative case
www.bmj.com/content/389/...

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Reposted by David Ludwig MD, PhD

Prof Jeffrey S Morris @jsm2334.bsky.social · Apr 28

In an associated opinion piece in STAT News (www.statnews.com/2025/04/22/n...),

Short-term diet trials are designed to fail

Does ultra-processed food cause obesity? Maybe, but we’ll never know from short-term trials.

www.statnews.com

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David Ludwig MD, PhD @davidludwigmd.bsky.social · Apr 27

Designed to Fail:

Why short-term diet trials cannot solve the epidemics of chronic disease.

👉New blog post (no paywall)

Designed to Fail: Why Short-term Diet Trials Cannot Solve the Epidemics of Chronic Disease

A version of this essay was published in STAT News First Opinion on April 22

davidludwigmd.medium.com

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David Ludwig MD, PhD @davidludwigmd.bsky.social · Apr 22

Designed to Fail

Why short-term trials, like those in the $170M Nutrition for Precision Health initiative, cannot solve the epidemics of chronic disease.

Study in BMJ with Walt Willett and Mary Putt www.bmj.com/content/389/...

Opinion in @statnews.com
www.statnews.com/2025/04/22/n...

Wash-in and washout effects: mitigating bias in short term dietary and other trials

Short term trials with surrogate measures instead of hard outcomes are often used to study chronic diseases. The effects of an intervention may, however, take time to develop and persist after discont...

www.bmj.com

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David Ludwig MD, PhD @davidludwigmd.bsky.social · Apr 3

Fascinating review cancer cell metabolism.

Most cancer treatments harm the "host" (ie, the patient), in addition to the tumor.

With knowledge of metabolism, we might be able to:

👉Attack the tumor AND
👉Support the host

Tumor metabolism as a factor affecting diversity in cancer cachexia | American Journal of Physiology-Cell Physiology | American Physiological Society

Cancer cachexia is a multifaceted metabolic syndrome characterized by muscle wasting, fat redistribution, and metabolic dysregulation, commonly associated with advanced cancer but sometimes also evide...

journals.physiology.org

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David Ludwig MD, PhD @davidludwigmd.bsky.social · Apr 2

Important paper on risk factors and life expectancy worldwide.

Action mostly with smoking, diabetes, BP, weight. Less so with LDL chol.

(Probably written by a committee: 👉"modification of smoking ... was associated with the most additional life-years free of death")
www.nejm.org/doi/abs/10.1...

Global Effect of Cardiovascular Risk Factors on Lifetime Estimates | NEJM

Five risk factors account for approximately 50% of the global burden of cardiovascular disease. How the presence or absence of classic risk factors affects lifetime estimates of cardiovascular dise...

www.nejm.org

Reposted by David Ludwig MD, PhD

Pamela Ferdinand @pamelawrites.bsky.social · Feb 25

“Infants may consume upwards of 60 grams of added sugars per day, or the equivalent of two soft drinks per day if they are entirely formula-fed,” researchers say in the study, published yesterday [Feb. 24, 2025] in the Journal of Food Composition and Analysis.

usrtk.org/healthwire/i...

Most U.S. infant formulas contain mainly added sugars, posing a serious risk to babies' health, researchers say

Most infant formulas in the U.S. contain mostly added sugars instead of natural lactose, which experts say can harm early development, a new study shows.

usrtk.org

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David Ludwig MD, PhD @davidludwigmd.bsky.social · Jan 25

Anti-depressant therapy for Danish winter.

👉Hellerup harbor, water temp 2° C

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David Ludwig MD, PhD @davidludwigmd.bsky.social · Jan 10

Will a Low-Carb Diet Reduce Racial & Ethnic Health Disparities?

No paywall at this link:

Will a Low-Carb Diet Reduce Racial & Ethnic Health Disparities?

Coauthored with Nicholas Norwitz, Diana Thomas, and Cara Ebbeling. Image modified from ChatGTP by Mr Andrew Degryse

medium.com

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David Ludwig MD, PhD @davidludwigmd.bsky.social · Dec 21

NOON, Denmark. Circa solstice. View to the South.

In case you were wondering, that moderately bright object about 10° above the horizon is ... the sun 😲

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